Impact Assessment of Invasive Plant Species in Selected ... · Species in Selected Ecosystems of Bhadaure Tamagi VDC , ... Borreria alata, Eichhornia ... Impact Assessment of Invasive

Impact Assessment of Invasive Plant Species inSelected Ecosystems of Bhadaure Tamagi VDC, Kaski

An Ecosystem-based Adaptation in Mountain Ecosystem in Nepal

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Published by: IUCN Nepal, Kupondole, Lalitpur, Nepal

Edited by: Amit Poudyal & Anu Adhikari, IUCN Nepal

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Language editing: Dr. Bishnu Hari Baral

Copyright: © July, 2013 International Union for Conservation of Nature and Natural Resources

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This Report has been published under ‘Ecosystem-based Adaptation in Mountain Ecosyestem’ Project, jointly

implemented by International Union for Conservation of Nature (IUCN), United Nations Development Programme

(UNDP) and United Nations Environment Programme (UNEP) with financial support from Germany’s Federal

Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU).

supported by:

Research Team:Ripu M KunwarRam P Acharya

Technical Advisor Team of IUCN Nepal:Anu AdhikariRajendra KhanalRacchya ShahSony BaralDr. Yam Malla

Impact Assessment of Invasive Plant Species in Selected Ecosystemsof Bhadaure Tamagi VDC, Kaski

Impact Assessment of Invasive Plant Species inSelected Ecosystems of Bhadaure Tamagi VDC, KaskiAn Ecosystem-based Adaptation in Mountain Ecosystem in Nepal

ACKNOWLEDGEMENTS

IUCN, International Union for Conservation of Nature, is thankful to Practical Solution Consultancy

Nepal Pvt Ltd (PSPL) for conducting this study on “Impact Assessment of Invasive Plant

Species in Selected Ecosystems of Bhadaure Tamagi VDC , Kaski ” and support to prepare

this document in the present form. Precisely, Mr. Ripu M Kunwar and Mr. Ram P Acharya of

PSPL are sincerely acknowledged.

The residents of Bhadaure Tamagi VDC, Kaski are highly appreciated for their supports to carry

out the field study. We are also indebted to those organizations and individuals, who spent their

precious time during consultations, discussions, meetings and field observations.

Last but not least we would like to express our gratitude to all individuals who helped us in one way

or another.

July, 2013

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EXECUTIVE SUMMARY

The Convention on Biological Diversity (CBD), 1992 underlines that the biological invasion ofalien species is the second worst threat after habitat destruction and set global priorities andguidelines to collect information and coordinate international actions on invasive alien speciesmanagement. However, approaches taken to combat invasive species and even the data onwhich they should be based are clearly inadequate to deal with the onslaught of invasivespecies in Nepal. Building resilience against climate change and invasive species in both humanand ecological systems to an optimum level is the best possible way of adaptation. Therefore,Ecosystem-based adaptation (EbA) is gaining momentum as a cost-effective means of protectinghuman and ecological communities against the impact of climate change and emerging biologicalinvasions. The present study was the first attempt to identify EbA options for building resilience ofnature and communities against climate change and biological invasions in Bhadaure TamagiVDC of Panchase through a study of various dynamics of invasive species and their management.In particular, biological invasions of nilo gandhe (Ageratum conyzoides) and kalo banmara (Ageratinaadenophora) were studied and their management through EBA options was scoped.

Field visits were made in December 2012 and a total of 58 respondents from 10 study sites(Bhadaure, Bhanjyang, Chainpur, Damdame, Ghatichina, Harpan, Kutmidanda, Sidhane, Tamagiand Thulakhet) were interacted with. Questionnaires were administered to collect data on theexisting colonies of selected species, their introduction, establishment and spread, impacts,and management measures. In addition to questionnaire surveys, six focus group discussionswere held at Bhanjyang, Chainpur, Ghatichina, Harpan, Tamagi and Thulakhet. The colonieswith different population intensity of the selected species were identified as dense, moderate andfair/sparse during discussions and each was sampled in 13 different sites at altitudes between821m and 2096 m. Altogether 54 transects were laid for a vegetation study. Some transects werelaid perpendicular to the road and others parallel to the road at 10 m to 100 m distance. Eachtransect was studied for its vegetation by laying one or two quadrats measuring 10 m x 10 m,depending on field situations. Diversity and distribution of Ageratum and Ageratina were accountedin 1 m x 1 m and 2 m x 2 m quadrats respectively. Soil, precipitation and temperature wereanalyzed with respect to diversity, distribution and invasion trend of the selected IAS. To locatethe study area and sites, and trace the distribution of species and model of the potential areaof invasionability, geo-coordinates were synchronized with Geographic Information System(GIS) mapping. River, road, land use data (settlements, forests and agricultural lands) andplant diversity and distribution were used to find the suitability index for invisibility.

Impacts of A. conyzoides and A. adenophora were well observed through out Bhadaure TamagiVDC and none of the ecosystems was found free from this menace. Edges of forests, agriculturallands, wetlands and roads deteriorated due to invasion. The abandoned agricultural lands andforests served as a good refuge for A. conyzoides and A. adenophora respectively. Roadsides,grazing lands, edges of wetlands were co-invaded. A total of 140 plant species were recordedduring field visits, among them 52 invasive and 18 high risk possessing. There were 12 potentiallycompetitors invasive species which can establish where and when habitats are poorly nurturedand abandoned. Local communities were aware of only about the invasion of nine IAS: A. conyzoides,A. adenophora, Chromolaena odorata, Phalaris minor, Conyza japonica , Borreria alata, Eichhorniacrissepes, Parthenium hysterophorus and Lantana camara. The first IAS in Bhadaure TamagiVDC were ratnaulo (P. minor) and salah jhar (C. japonica) that came into account some 30 yearsago. Badame jhar (B. alata) was introduced and established on agricultural lands some 20 yearsago. Recently, seto jhar (C. odorata) has been introduced in the roadsides and fallow lands of theVDC. A. adenophora was introduced and established a decade ago in the VDC and colonizedalong the roadsides at first. With the help of vectors, it was spread in grazing lands and forestperiphery. Later, it was outcompeted by A. conyzoides. A. conyzoides was introduced in Bhadaure

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Tamagi about 5-7 years ago. It has aggressively spread as low quality fertilizers with high nitrogencontent were used. Along with these nuisance invasive species, there were introduction andestablishment of Jalkumbhi (E. crissepes), Madhesi pati (P. hysterophorus) and Kande banmara(L. camara) in and around Bhadaure Tamagi VDC, possessing a potential risk to the local biodiversityand socio-economy. As increasing number of IAS and temperature of Bhadaure Tamagi areconcomitant, the intensive spread of IAS is likely unless the current management system isstrengthened. Chainpur, Sidhane, Harpan, Tamagi and Kutmidanda were prone to further invasion.Therefore, all preventive, controlling and adaptation based measures are requisite to offset theinvasion.

Chainpur, Harpan and Kutmidanda of the VDC were more susceptible to invasion of A. conyzoidesand again Chainpur, Harpan and Tamagi were likely to be abraded by A. adenophora. A. adenophorawas most successful in sites above 1400 m, but in lower sites it was co-invaded by A. conyzoides.Species like pati (Artemisia), kantakari (Solanum xanthocarpum) and sisnu (Urtica) on roadsidesand fallow lands, and banso (Setaria pallidesesca), samo (Panicum colonum), phurke (Pittosporumnapaulense), mallido (Ischaemun rugosum), siru (Imperata cylindrical), etc. on agricultural landswere particularly threatened by A.conyzoides and A. adenophora. A. conyzoides is more harmfulto the local livelihood and biodiversity than A. adenophora. Neither cattle nor goats feed on Ageratum,and the areas traditionally used for grazing in the upper areas of the VDC were deteriorated.Incidents of livestock mortality were common in the village because of accidental consumption ofAgeratum and its flowers by livestock while feeding grasses. In the last five years, there were threecasualties of livestock mortality only in Harpan of Bhadaure Tamagi. Agricultural crops, particularlyginger, millet and rice and grasses were outcompeted by Ageratum and their productivity wasdeclined. Poor agricultural productivity was one of the reasons of depopulation of the ruralareas. Inadequate human resources in the VDC have led to agriculture and grasslands lessnurtured and unattended, inducing rampant spread. Current livelihood pattern amplifiedintroduction of non-native species because of more interest in off-farm activities, new species andvarieties, and less interest in seeds, fertilizers, land and soil fertility. Consequently, farmers ofBhadaure Tamagi VDC have been plagued by an increasing number of invasive weeds. Despite anumber of impacts of IAS have been witnessed, a detailed species specific impact assessmentfor each habitat and ecosystem is yet to be carried out.

With changing population and declining productivity of farmland, generating alternative sourcesof income is essential. It is important to promote activities that balance the need for conservingbiodiversity and meeting the requirements of local communities on the one hand and promotingtechnology and skills that can offset the invasion of IAS on the other. Effective management ofbiological invasion should consist of three main steps : prevention, early detection anderadication. Then the control of invasion should be backed up by integrated management. Theprecise management measures adopted for any plant invasion will depend upon factors suchas institutional mechanism, policy structures, terrain, the cost and availability of labour, theseverity of the infestation and presence of other invasive species.

The first and foremost principle of prevention is avoiding invasive species. For this, a list of invasivespecies of an area should be enumerated and widely circulated through the media for awarenessof the general public. The participation of communities should be promoted by raising theirawareness and involving them in efforts to address IAS through promotion of the Public-PrivatePartnership (PPP) approach. Guiding local communities and stakeholders to the judicious usesof materials that limit introduction and spread of invasive aliens is important. The land use ofthe VDC needs to be monitored and nurtured regularly for controlling invasion of species. A.adenophora cannot invade dense canopy forests, shrub lands, and well-managed plantations.Therefore, plantation, afforestation and promotion of native fodder and forage species inabandoned and fallow lands should be encouraged to maintain canopy and ground coverage.Plantation of F. glaberrima complements the open canopy, chokes the introduction of invasivealiens and provides fodder to livestock. Until there is any firm conclusion to indicate otherwise,plantation of non-native and invasive species should be discouraged (Tiwari et al. 2005).

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As Ageratum and Ageratina are useful for various purposes, their extensive use may controltheir rampant spread. Extensive utilization is important as the strategy is called a win-win strategyand it has a good scope for enterprise development, employment generation at the local level,and long-term management of invasive species. Complete uprooting, including all roots androotlets, before flowering is mandatory and controlled burning, composting, manuring and usingis necessary. Integrated crop management with prescribed burning, regular weeding, hoeingand uprooting invasive alien species generally results in an increase in abundance and diversityof native species and crops.

Overall institutional facilities and human capacity need to be improved by providing essentialtechnical support, strengthening coordination and sharing IAS information among the agenciesconcerned and stakeholders. Invasive alien species are a global issue that requires collaborationamong governments, the economic sector and non-governmental and internationalorganisations. Establishment of baseline data and regular monitoring of alien species dynamicsare essential to fully understand IAS problems and their impacts. Therefore, extensive andintensive research should be promoted. Scientific research is necessary to prepare basic data ofspecies, biology, ecology, impact assessment and management guidelines.

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ACRONYMS & ABBREVIATIONS

a.s.l. Above Sea Level

BMU Federal Ministry of Environment, Nature Conservation and Nuclear Safety, Germany

BRH Biotic Resistance Hypothesis

CABI Centre for Agricultural Bioscience International,

CBD Convention on Biological Diversity

CBO Community Based organization

CF Community Forest

CITES Convention on International Trade in Endangered Species of Wild Fauna and Flora

CNP Chitwan National Park

CO2 Carbon dioxide

DHM Department of Hydrology and Meteorology

ERH Enemy Release Hypothesis

FAO Food and Agricultural Organization

FGD Focus Group Discussion

GIS Geographic Information System

GISD Global Invasive Species Database

GISP Global Invasive Species Programme

GoN Government of Nepal

GPS Global Positioning System

IAS Invasive Alien Species

ICM Integrated Crop Management

IPCC Intergovernmental Panel on Climate Change

ISSG Invasive Species Specialist Group

IUCN International Union for Conservation of Nature

KIS Key Informant Survey

MEA Millennium Ecosystem Assessment

mm Milli meter

MoFSC Ministry of Forests and Soil Conservation

MoSTE Ministry of Science, Technology and Environment

NBS Nepal Biodiversity Strategy

NTFPs Non Timber Forest Products

NWH Novel Weapon Hypothesis

PSPL Practical Solution Consultancy Nepal Pvt. Ltd

VII

SM Social Mobilizer

SSC Species Survival Commission

UNDP United Nations Development Programme

UNEP United Nations Environmental Programme

UNFCCC United Nations Framework Convention on Climate Change

VDC Village Development Committee

VIII

TABLE OF CONTENTS

ACKNOWLEDGEMENTS .......................................................................................................... IEXECUTIVE SUMMARY .......................................................................................................... IIIACRONYMS & ABBREVIATIONS......................................................................................... VII

CHAPTER ONE: INTRODUCTION ........................................................................................... 11.1 Background ........................................................................................... 11.2 Invasive Alien Species (IAS) ........................................................................................... 11.3 Invasive Alien Plant Species ........................................................................................... 11.4 Management Measures ........................................................................................... 21.5 Ecosystem-based Adaptation in Nepal ......................................................................................... 31.6 Objectives of The Study ........................................................................................... 31.7 Scope of The Study ........................................................................................... 41.8 Limitations of The Study ........................................................................................... 41.9 Organization of The Report ........................................................................................... 4

CHAPTER TWO: METHODOLOGY ........................................................................................... 52.1 Study Area: Panchase ........................................................................................... 52.2 Study Site: Bhadaure Tamagi VDC ........................................................................................... 62.3 Study Approaches ........................................................................................... 6

2.3.1 Multi-disciplinary and cross-sectional ............................................................................ 62.3.2 Participatory and consultative ........................................................................................ 62.3.3 Ecology and field-based ........................................................................................... 7

2.4 Study Methods ........................................................................................... 72.4.1 Desk review ........................................................................................... 72.4.2 Focus group discussion ........................................................................................... 72.4.3 Household survey ........................................................................................... 72.4.4 Ecological assessment ........................................................................................... 82.4.5 Soil test ........................................................................................... 92.4.6 Meteorological study ........................................................................................... 92.4.7 Geographic Information System (GIS) mapping ........................................................... 92.4.8 Data analysis ......................................................................................... 10

CHAPTER THREE: FINDINGS ......................................................................................... 113.1 Socio-economy ......................................................................................... 113.2 Biophysical Setting ......................................................................................... 113.3 Climate ......................................................................................... 113.4 Biodiversity ......................................................................................... 123.5 Invasive Alien Plant Species ......................................................................................... 133.6 Invasive Alien Plant Species: Ageratum conyzoides and Ageratina adenophora ...................... 14

3.6.1 Profile of selected species ......................................................................................... 143.6.1.1 Ageratum conyzoides ................................................................................................ 143.6.1.2 Ageratina adenophora .............................................................................................. 16

3.6.2 Diversity and distribution ......................................................................................... 193.6.3 Potential invasion ......................................................................................... 203.6.4 Characteristics of invasive alien species ..................................................................... 223.6.5 Mechanism of invasion ......................................................................................... 233.6.6 Causes of invasion ......................................................................................... 233.6.7 Invasion trend of alien species .................................................................................... 24

3.6.8 Impacts of invasive species ......................................................................................... 253.6.8.1 Biodiversity threats .................................................................................................. 263.6.8.2 Impacts at ecosystem level ....................................................................................... 263.6.8.3 Impact on soil .................................................................................................. 273.6.8.4 Impacts at species level ............................................................................................ 293.6.8.5 Impacts at socio-economic level ............................................................................... 29

3.6.8.5.1Negative impacts ........................................................................................ 303.6.8.5.2 Positive impacts ......................................................................................... 32

3.6.9 Climate change and invasive species ......................................................................... 333.7 Management of invasive species ......................................................................................... 34

CHAPTER FOUR: CONCLUSION AND WAY-FORWARD...................................................................... 354.1 Conclusion ......................................................................................... 354.2 Recommendations ......................................................................................... 36

4.2.1 Preventive Measures ......................................................................................... 364.2.2 Controlling Measures ......................................................................................... 374.2.3 Actions ......................................................................................... 39

CHAPTER FIVE: BIBLIOGRAPHY ......................................................................................... 41ANNEX ......................................................................................... 48

Annex 1. List of respondents for study of IAS in Bhadaure Tamagi VDC, Panchase ................ 48Annex 2. Questionnaire used for survey ..................................................................................... 50Annex 3. Per Month Maximum Temperature Record ................................................................. 54Annex 4. Per month minimum temperature record .................................................................... 55Annex 5: Total Species and their Frequency in Different Habitats ............................................. 56Annex 6. List of invasive plant species in Bhadaure Tamagi, Panchase and Nepal ................. 60Annex 7: Definitions of key terms ......................................................................................... 66

LIST OF FIGURES

Figure 1: Study area and sites .................................................................................................................. 5Figure 2: Group discussion at Bhadaure .................................................................................................. 7Figure 3: Layout of transect and sample quadrat ..................................................................................... 9Figure 4: Ecological sampling ................................................................................................................... 9Figure 5: Temperature and precipitation at Lumle station, close to Bhadaure Tamagi VDC .................12Figure 6: A threatened plant species Cythea spinulosa (tree fern) at Tamagi and orchids

at Harpan, Panchase ...............................................................................................................13Figure 7: Distribution of A. conyzoides in Bhadaure Tamagi VDC ........................................................15Figure 8: A. conyzoides, a weed is dominating agriculture fields when they are less nurtured ............16Figure 9: Distribution of A. adenophora in Bhadaure Tamagi VDC ........................................................17Figure 10: A. adenophora growing along the edges of roads, canals, rivers and ponds ........................17Figure 11: Importance Value Index of IAS in Bhadaure Tamagi VDC, Panchase ...................................18Figure 12: Invasion maps for A. conyzoides, A. adenophora and both species ......................................21Figure 13: Characteristics of invasive alien species .................................................................................22Figure 14: Mechanism of invasion of IAS .................................................................................................22Figure 15: History of introduction of invasive alien plant species in Bhadaure Tamagi VDC ..................24Figure 16: Impact of IAS on different habitats ...........................................................................................26Figure 17: A house owned by a Gurung left unattended for long at Tamagi, Bhadaure Tamagi VDC ....30Figure 18: Ginger has been outcompeted by Ageratum at Chainpur and grassland has been

relegated by Ageratina at Tamagi ............................................................................................31Figure 19: Uses of A. adenophora: tender shoots are as forage, green manuring and green fuel ........33Figure 20: Relationship of IAS introduction and increasing temperature in Bhadaure Tamagi VDC ......33Figure 21: Ficus glaberrima (Pakhuri) controlling invasive aliens in its shade ........................................37Figure 22: A gall made by Procecodocharis utilis, gall fly in A. adenophora ...........................................38

LIST OF TABLES

Table 1: Details of quadrats laid at the sites of Bhadaure Tamagi VDC ................................................ 8Table 2: Research plots and area sampled ............................................................................................. 8Table 3: Temperature characteristics of Lumle, a nearby station of Bhadaure Tamagi VDC ............... 11Table 4: Worst IAS and their frequency in Nepal and Panchase ..........................................................13Table 5: Density and frequency of the selected IAS (A. conyzoides and A. adenophora) ...................19Table 6: Potential invasion map .............................................................................................................20Table 7: Causes and factors for invasion (N = 28) ................................................................................24Table 8: Information about the first sight of IAS in the Panchase area by local communities

(N =28) .....................................................................................................................................25Table 9: Physical characteristics of soil of Bhadaure Tamagi VDC ......................................................28Table 10: Chemical characteristics of soil of Bhadaure Tamagi VDC.....................................................28Table 11: Correlation analysis among soil characters, altitude and IVI of A. conyzoides and

A. adenophora .........................................................................................................................28Table 12: Impact of invasive alien species at species level ....................................................................29Table 13: Impacts of A. conyzoides and A. adenophora .........................................................................31Table 14: Usage of different plant species as green manuring ...............................................................32Table 15: Comparative use of A. conyzoides and A. adenophora ..........................................................32Table 16: Management measures to control IAS in Bhadaure Tamagi VDC (N = 28) ...........................34

Impact Assessment of Invasive Plant species in Selected Ecosystems of Bhadaure Tamagi VDC, Kaski

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CHAPTER ONE: INTRODUCTION

1.1 Background

Climate change and invasive species present two of the greatest threats to biodiversity and theprovision of valuable ecosystem services (Burgiel and Muir 2010). Climate change contributesto erratic rainfall, drying up of local springs and streams, adjustment of species distribution,phenology and morphology, shift in agriculture calendar, emergence of invasive species andoutbreak of diseases and pests, etc (IPCC 2007). Precisely, climate change impacts, such aswarming temperatures and changes in CO2 concentrations, are likely to increase opportunitiesfor introduction of invasive species because of their adaptability to disturbance and to a broaderrange of biogeographic conditions and environmental controls (Mooney and Hobbs 2000).Warmer temperature may also facilitate the movement of invasive species along previouslyinaccessible pathways of spread in both natural and human-made environments (Engel et al.2011), because invasive species have a broader range of tolerance (Walther et al. 2009).

It is estimated that biological invasions can have strong effects on structure and function ofecosystems that are responding to a changing climate and climate change is also changing thecontext in which potential invasive species succeed or fail (Husain and Agnihotri 2009). However,relationship of biological invasion of alien plant species and climate change and their managementare hitherto unknown in Nepal, despite Article 8(h) of CBD urged parties to prevent the introductionof, control or eradicate those alien species which threaten ecosystems, habitats and species(CBD 1992) (www.biodiv.org).

1.2 Invasive Alien Species (IAS)

IUCN (2000) defines IAS as an alien species, which becomes established in natural or semi-natural ecosystems or habitat, an agent of change, and threatens native biological diversity. IASoccurs in all major taxonomic groups. Within each taxon, numerous species including perhapsas many as 10 per cent have potential to invade other ecosystems (Rejmanek et al. 2000). IAScan transform the structure and species composition of ecosystems (Ricchardi et al. 2000) byestablishing viable populations with growth rates enough to displace elements of native biota(Rejmanek 1999) or to modify disturbance regimes (Brooks et al. 2004), thereby potentiallychanging ecosystem structure and functioning (Dukes and Mooney 2004), or by outcompetingnative denizens for resources by changing the way nutrients are cycled through the system.

IAS endangers the environment, economy and human welfare (Lodge et al. 2006). It also reducesbiodiversity, replaces important native species and increases investment in agriculture andsilviculture (Ricchardi et al. 2000), disrupting prevailing vegetation dynamics and nutrient cycling(Richardson 1998). The estimated damage from invasive species worldwide totals more thanUS $1.4 trillion a year (5 percent of the global economy) with impacts across a wide range ofsectors, including agriculture, forestry, aquaculture, transportation, trade, power generation andrecreation (Stern 2006). Since the 17th century, IAS contributed to nearly 40 percent of all animalextinctions for which the cause is known (CBD 2006). The share of invasive plants to damage isaround 10 percent of the total.

1.3 Invasive Alien Plant Species

A list of invasive alien plant species is available for most regions, though the list is to be updatedand reviewed routinely. Nepal is not exempt and there are handful studies of invasive species.Though the first study of invasive alien species of Nepal was carried out for over five decades


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(Banerji 1958), impacts and management studies of IAS at species, ecosystem and socio-economic levels through eco-friendly approaches were parsimoniously carried out. Poudel andThapa (2012) reviewed 43 studies so far conducted in Nepal related to invasive plant species,and they recommended for more researches on documentations and impacts of invasive alienplant species. A total of 166 invasive alien plants species of Nepal were noted by IUCN (Tiwariet al.2005). However, in a milieu of changing climate, introduction and aggressiveness of invasivealien species is being increased, urging more researches and updates on IAS.

The world’s 100 worst invasive aliens (Lowe et al. 2000) include 11 plant species (Arundodonax, Chromolaena odorata, Eichhornia crissepes, Hedychium gardnerianum, Hiptagebenghalensis, Imperata cylindrica, Lantana camara, Leucaena leucocephala, Mikania micrantha,Opuntia stricta and Rubus ellipticus) that are found in Nepal. However, they are not equallyinvasive. Seven toppers alien invasive in the list for Asia Pacific region include: Ageratinaadenophora, Ageratum conyzoides, Chromolaena odorata, Eichhornia crissepes, Lantanacamara, Mikania micrantha and Parthenium hysterophorus (Sankaran et al. 2005). All theseseven species are problematic in Nepal.

The impacts of those invasive plant species may be more severe as they increase both innumbers and extent, and as they compete for diminishing resources such as water and soilminerals. Invasive alien plant species can threaten those basic needs and compromise ecosystemfunctions by taking advantage of habitat disturbance, species under stress and other chinks inthe armor of otherwise healthy systems. This affects the multiple roles of ecosystems in providingprovisioning, regulating, supporting and cultural services (MEA 2005, Vila et al. 2009). Therefore,global efforts are being made to control these invaders. Whatever the cost may be, the unintendedspread of invasive species continues unabated, despite the earnest efforts are being made tomanage them (Sankaran et al. 2005).

1.4 Management Measures

Article 8(h) of the CBD states : “Each contracting party shall, as far as possible and as appropriate,prevent the introduction of, control or eradicate those alien species which threaten ecosystems,habitats or species”. The CBD (1992) sets global priorities, guidelines, collects information andhelps to coordinate international action on invasive alien species. However, approaches takento combat invasive species and even the data on which they should be based are clearlyinadequate to deal with the onslaught of invasive species in Nepal. Similarly, from a conservationperspective, there is little point to addressing climate change if the biodiversity we are trying toprotect has already been lost to invasive species. Because the numbers of invasive plant speciesand the extent of invasions are rapidly increasing at multiple scales resulting grown concernsabout the stability of ecosystems (Hobbs et al. 2006). Therefore, the management of invasivespecies demands a hierarchical perspective where the preference, resources and capacity aremost; first to prevent, second to control and third to eradicate biological invasions (CBD 2002,Wittenberg and Cock 2001).

Again building resilience in both human and ecological systems to an optimum level is the bestpossible way to adapt to climatic variation.Therefore, Ecosystem-based Adaptation (EbA) isgaining momentum as a cost-effective and eco-friendly means of protecting human and ecologicalcommunities against the impacts of climate change and biological invasion (Heller and Zavaleta2009, Mooney et al. 2009). EbA is described as building nature’s resilience to the impacts ofclimate change, while also helping to meet people’s basic needs. Such an approach can alsoprovide an integrative framework to address impacts from both climate change and invasivespecies (Burgiel and Muir 2010).


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1.5 Ecosystem-based Adaptation in Nepal

Ecosystem-based Adaptation (EbA) is the use of biodiversity and ecosystem services as part ofan overall adaptation strategy to help people to adapt the adverse effects of climate change. Itaims at maintaining and increasing the resilience and reducing the vulnerability of ecosystemsand people in the face of the adverse effects of climate change. It can generate significantsocial, economic and cultural co-benefits, contribute to the conservation of biodiversity, andbuild on the traditional knowledge and practices of indigenous peoples and local communities,including the important role of women as custodians of local knowledge (www.iucn.org). Inpromoting the sustainable use of nature and biodiversity, EbA strategies provide policy coherencewith national and international commitments.

The EbA Project for Mountain Ecosystems in Nepal, Peru and Uganda aims at strengtheningcapacities of these three countries which are particularly vulnerable to climate change impacts.The project targets to strengthen ecosystem resilience of these countries and reduce vulnerabilityof local communities with particular emphasis on mountain ecosystems. It is designed on thepremises that social/human adaptation is best achieved by ensuring continued provision ofecosystem services and enhancing human capacities to address current climatic challengesand future uncertainties. With funding from German Government, Federal Ministry of Environment,Nature Conservation and Nuclear Safety (BMU) through its International Climate Initiative, theEbA project is jointly implemented by the International Union for Conservation of Nature (IUCN),the United Nations Environmental Programme (UNEP) and the United Nations DevelopmentProgramme (UNDP). In Nepal, the Ministry of Forests and Soil Conservation (MoFSC) is theimplementing agency at the national level, and the Ministry of Science, Technology andEnvironment (MoSTE) plays an overall coordinatiing role. The project has four major components(i) development of methodolgy and tools for mountain ecosystems; (ii) application of abovetools and methodology at the national level; (iii) implementation of pilot EbA at the ecosystemlevel; and (iv) formulation of national policies and building an economic case for EbA at thenational level.

The pilot site for this project in Nepal is the Panchase area, a cross-point of Kaski, Parbat andSyangja districts. The area is vulnerable to climate change, with negative impacts on forests,water resources, agriculture and biodiversity. Panchase is a protected forest and has been thefocus of national, regional and local development strategies and plans considering its highnatural resource significance as well as its potential for tourism, preferably eco-tourism (GoN2012a). With increasing trend of abandonment of previously productive land, Bhadaure TamagiVDC of Panchase is largely witnessing invasion of alien plant species, especially with apparentimpacts on connected ecosystems (UNDP/MDO 2006). Therefore, this VDC has been selectedfor the present assessment of climate change and plant species invasion for developing EbAoptions for building resilience of local communities and ecosystems.

1.6 Objectives of The Study

The main objective of the study was to assess the impact of major invasive plant species ofBhadaure Tamagi VDC of the Panchase area and recommend potential Ecosystem-basedAdaptation options for resilience of local ecosystems and communities to address the impactand maintain ecosystem. The specific objectives of the study were to:

• assess the current status of invasive plant species in Bhadaure Tamagi VDC;

• find out the trend and various dynamics of invasion of two major invasive alien plant species (Ageratum conyzoides and Eupatorium adenophorum);

• study the impact posed by A. conyzoides and E. adenophorum on major ecosystems (forests, agriculture, grazing lands and wetlands); and

• recommend potential EbA options for resilience of local ecosystems and communities following the assessment.


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1.7 Scope of The Study

Scope of the study was to analyse the impact of two major invasive alien plant species(A. conyzoides and A. adenophora) of Bhadaure Tamagi VDC of Panchase area, and proposepotential Ecosystem-based Adaptation options for resilience of local ecosystems and communitiesto address the prevailing impacts and threats posed by them and other associated determinants.The study was also meant to assess the current status and invasion trend of these species inBhadaure Tamagi VDC, and recommend a set of management prescriptions that are practical,doable and implementable in the context of the Panchase ecosystem.

1.8 Limitations of The Study

The study was carried out between 15 to 25 December 2012, with a very short period for thefield visit. As December is a post-harvesting season of rice, there were constraints to observethe impact of IAS on agricultural crops, including rice. As the field visit was conducted in winter,the assessment of reproductive biology of selected species and the cross-cutting impact of thespecies were also limited.

Limited field visit led to limited sampling and consultations. Only the frequency of associatedspecies and the frequency and density statistics of sample species were enumerated becauseof limited field visit. Community perception and literature were frequently used for impactassessment and trend dynamics. The species sampled were habitat specific and the study areawas physiographycally complex. Therefore, varied transects were laid for sampling.

1.9 Organization of The Report

This report has been divided into five chapters. Chapter one deals with introduction, background,objectives and scope of the study, and organisation of the report. Chapter two outlines the studyarea and sites, study approaches, materials, and methods adopted. Chapter three presentsfindings of the study such as biodiversity and invasive species of the area, accounts of invasivespecies and their impact and prevailing management measures, and Chapter four portraysmajor conclusions, actionable management options and recommendations. In the report,Ageratina adenophora is interchangeably used with Eupatorium adenophorum because theyare synonyms. Again, the generic names of Ageratum conyzoides and Ageratina adenophoraor Eupatorium adenophorum are sometimes abbreviated.


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CHAPTER TWO: METHODOLOGY

2.1 Study Area: Panchase

The Panchase area was selected as a study area and its Bhadaure Tamagi VDC as a study site(Figure 1). Panchase is situated at the junction of Kaski, Parbat and Syangja districts.Geographically, it is located in the mid- hills of Nepal, just west of Pokhara, between latitudes280 12’ and 280 18’ N, and longitudes between 830 45’ and 830 57’ E. This region is denselypopulated by subsistence farmers and livestock rearing is an integral part of their livelihood.Altitude ranges from 815 m at the Harpan River to 2517 m at the peak of the Panchase hill.Forests are located at 1450 m and above. Annual precipitation in here is 5000mm (UNDP/GEF2006).

The Panchase hill is the origin of many rivers and tributaries that supply water to lowland villages,and a primary source for Phewa Lake. The lower limit of Panchase is enriched by flooded riversand agricultural lands. Panchase has a variety of terrain and climatic variations ranging fromupper tropics to moist temperate. It also has a great diversity of ecosystem and plant species.

Figure 1: Study area and sites


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The Panchase area has hill sal forests, pine forests, Schima-Castanopsis forests, alder forests,lower temperate oak forests, and oak-laurel forests. At present, 68.69 percent of the forests ofthe area is conserved as protected forests and the rest as community forests (Aryal and Dhungel2009).

Common fodder trees of the Panchase area are: pakhuri (Ficus glaberrima), dudhilo (Ficusnerifolia), nimaro (Ficus roxburghii), kabhro (Ficus lacoor), khanyu (Ficus semicordata), gogan(Sasaurrea napalensis), badahar (Artocarpus lakoocha), bedulo (Streblus asper), etc. tejpat(Cinnamomum tamala), sugandhkokila (Cinnamomum glaucescens), amriso (Thysanolaenamaxima), chiraito (Swertia chirayita), timur (Zanthoxylum armatum), lapsi (Choerospondiasaxillaris), kurilo (Asparagus racemosus), etc are common NTFPs of the area. Besides these,chiraito (Swertia chirayita), satuwa (Paris polyphylla) and Kurilo (Asparagus Racemosus) areimportant medicinal plants with high market value. The Panchase area holds immense potentialfor establishing micro-enterprises based on several NTFPs like lokta (Daphne bholua), mollah(Viburnum mullaha), allo (Girardinea diversifolia), nigalo (Arundinaria species), etc. Lokta canbe used for making Nepali paper, allo for weaving cloth, nigalo for making bamboo products,and mollah for extracting valuable juice with sweet and sour taste.

Ethnic composition of the Panchase area constitutes Brahmin, Kshetri, Gurung, Bishwokarma,Nepali, Pariyar, Magar, Thakali, etc. Gurung communities reside at higher elevations and Brahminand Kshetri at lower elevations. Of these, Gurung and Magar are indigenous to the area andBishwokarma, Nepali and Pariyar are disadvantaged groups. Approximately 40,000 people livein and around the Panchase area, sustaining their livelihood from exploitation of local resourcesand products (fodder, firewood, timber, edible, medicinal plants, etc) (Bhattarai et al. 2012).

2.2 Study Site: Bhadaure Tamagi VDC

Bhadaure Tamagi VDC is one of the largest VDCs of Panchase and it is dominated by theGurung ethnic group. The total area of the VDC is 15.07 km2. As in entire Panchase, Gurungand other ethnic groups reside at upper elevations and Brahmin and Kshetri at lower elevations.Most of the disadvantaged groups live at higher elevations. The VDC stretches at latitudesbetween 280 12’ 35" and 280 16’ 34", and longitudes between 830 48’ 14" and 830 52’ 52", andspans within 814 m to 2517 m. It has upper tropical to moist temperate bio-climate.

2.3 Study Approaches

2.3.1 Multi-disciplinary and cross-sectional

In accordance with the study goal, multi-disciplinary approaches as exploratory as well as cross-sectional in its content were used for the study. Literature review, community consultations,individual interviews, field observations, GIS mapping and cross-checking were used.

2.3.2 Participatory and consultative

Participatory and consultative approach was used to incorporate views and concerns of localcommunities (farmers, users, community forest user groups and stakeholders) who have longbeen inhabited in Panchase and utilized local resources for their livelihood. The approach wasadopted to reflect wider views and concerns of local communities who are directly or indirectlyencountered with invasive alien species during the course of livelihood.


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2.3.3 Ecology and field-based

Information generated in a participatory and consultative manner was recorded and verified atthe field level. Participatory cluster mapping was followed and information about abundanceand species threatened by invasive species were discussed in a participatory manner. Fieldobservations and sampling were useful in data and information verification and recording.

2.4 Study Methods

2.4.1 Desk review

Extensive desk review was done and data in general and of selected species was consolidated.In particular, species invasion, distribution, impacts, management and factors for spread of theselected species were appraised. About 100 literature were reviewed and used as referencesfor analysis of invasive aliens and their management.

2.4.2 Focus group discussion

Six focus group discussions were held afterestablishing prior oral informed consent withparticipating communities. Discussions were heldin Bhanjyang, Chainpur, Ghatichina, Harpan,Tamagi and Thulakhet based on consultationswith IUCN and MDO staff members. Colonies withdifferent population intensity of selected speciesas dense, moderate and sparse were identifiedduring discussions and each was sampled.Participatory mapping and recall methods wereused to elucidate the history of introduction andtrend of invasion and distribution. Informalmeetings were held in Bhadaure, Bhanjyang,Harpan and Thulakhet. Information from theconsultations was further cross-checked andverified with five key informants—school teacher,elderly person, woman, village representative andforest guard (Annex 1).

2.4.3 Household survey

A field visit was made in December 2012 and a total of 58 respondents from 10 study sites(Bhadaure, Bhanjyang, Chainpur, Damdame, Ghatichina, Harpan, Kutmidanda, Sidhane, Tamagiand Thulakhet) were consulted. A total of 28 individuals were interviewed during a householdquestionnaire survey and the rest during focus group discussions, using simple random andpurposive sampling techniques respectively (Annex 1). Information about existing colonies ofspecies, their introduction, establishment and spread, impacts, and management measures,etc were sought particularly from women, forest guards, elderly people and disadvantaged groupsduring the household questionnaire survey (Annex 2).

Figure 2: Group discussion at Bhadaure


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2.4.4 Ecological assessment

Following the participatory mapping of species specific population intensity, a rapid ecologicalassessment was carried out in 13 different sites (Table 1) following transect A-A’ (10-20 m wideand 50-100 m long based on physiography) study. Altogether 54 transects were laid for vegetationstudy. Some transects were laid perpendicular to the road and others parallel to the road at 10m to 100 m distance. In particular, the perpendicular transect was laid for Ageratum study andthe parallel transect was subjected to Eupatorium study. Each transect was studied for itsvegetation by laying one or two quadrats measuring 10 m x 10 m depending on field situation atthe left and right of the transect middle line in a spiral manner (Figure 3). One quadrat was laidin transects perpendicular to the road and two in parallel to the road. The quadrats were meantto study frequency and distribution of plant biodiversity. In each quadrat, two micro quadratsmeasuring 1 m x 1 m and 2 m x 2 m were laid respectively for the study of Ageratum andAgeratina (Table 2).

Figure 3: Layout of transect and samplequadrat

Table 1: Details of quadrats laid at the sites ofBhadaure Tamagi VDC

Table 2: Research plots and area sampled

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2.4.5 Soil test

Physicochemical properties of soil were analysed to see whether the selected species Ageratumand Ageratina are related to soil characters for their diversity and distribution. To assess thephysiochemical properties of soil underneath of Ageratum and Ageratina, a total of five soilsamples from Bhadaure-1 (northern part), Tamagi-3 (highest elevation of study sites), Chainpur-5 (east and lowlands of the VDC), Kutmidanda-7 (abandoned agricultural lands), and Sidane-8(west part of the VDC) were collected (Figure 4). Soil texture, pH and moisture of the sampleswere analysed in laboratory.

2.4.6 Meteorological study

Precipitation and temperature records of Bhadaure Tamagi VDC were collected from Lumlemeteorological station and the Department of Hydrology and Meteorology. Records from 1981to 2011 were available and collected for further analysis. Maximum and minimum temperaturesand rainfall were analyzed and plotted in a graph and a linear regression model was plotted toillustrate a trend in the last three decades. The missing data were not treated in any of thecalculations in this study.

2.4.7 Geographic Information System (GIS) mapping

Garmin Etrex Global Positioning System (GPS) was used to record the geo-coordinates ofsampling sites. The geo-coordinates were synchronized with Geographic Information System(GIS) mapping to locate the study area and sites, and trace the distribution of species andmodel of the potential area of invasionability of the selected species. River and road networks,and land use data (settlements, forests and agricultural lands) were used to find the suitabilityindex for invasionability, as the area with good moisture, road networks, nearby wetlands, andedges of forests and agricultural lands are the best conduits for invasive alien species. Thefollowing procedures were applied to model the invasion of the selected species:

• Field geo-coordinate points of the sampled species were collected.

• Landsat TM satellite imagery of 2012 was used for land use classification onthe basis of field training samples.

Figure 4: Ecological sampling


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• On the basis of classified image, the suitable area was identified through expertand grass roots- level knowledge and from the spatial analysis of severalparameters such as land use, river, road network, settlements, etc.

• Multi-criteria evaluation was performed on the basis of parameters selected forpotential area of invasion.

• Majorly overlay tools of ArcMap 10 were used for the overall analysis of potentialsites of IAS invasion in the study area.

• Suitability analysis of IAS was carried out on the basis of distance and frequencyof existing species in relation to land use, river and road. Spatial join wasperformed in the ArcMap 10 for distance analysis from river, road and particularland use such as forest, agriculture and settlement.

• The weighted overlay analysis was performed in the model builder to assignthe weight and scale range for each parameter based on the existing scenariosuch as how far a particular species is found in the field from river and road andin which land use class it is available.

• A potential invasion map of Eupatorium and Ageratum species was preparedfrom the analysis performed and further classified into four categories: highly,moderately, less and least potential sites of IAS.

2.4.8 Data analysis

Both quantitative and qualitative techniques were used for data analysis. The analysis wasdesigned specifically to triangulate the sources of evidence, rationalise information and interpretin a simple and understandable form. Climatic characteristics of the study area were assessedin terms of average annual maximum and minimum temperatures and annual precipitation byanalyzing the data recorded by DHM for Lumle station. GIS mapping was used for a graphicalpresentation of distribution and potential invasionability of the selected species. Field ecologicalsampling of vegetation and soil was carried out to see the relationship between soil and invasivespecies. Relevant photographs were taken and used as references for report.


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CHAPTER THREE: FINDINGS

This chapter discusses socio-economic, biophysical setting, climatic characteristics, biodiversityand invasive species of Bhadaure Tamagi VDC.

3.1 Socio-economy

Approximately 40,000 people live in the villages of the Panchase area and depend upon theforests for their livelihood (fodder, forage, fuelwood, timber, edible and medicinal plants). BhadaureTamagi, one of the largest VDCs of Panchase, has a population of 3,257 people living in 875households with average 3.72 members per household, which is less than national average(4.88)and district average (3.92) (GoN 2012b). About 50 percent of people depend on agriculture fortheir livelihood. The lower area of VDC is densely populated by subsistence farmers and livestockrearing is an integral part of their livelihood (Bhattarai et al. 2012). The upper area of the VDC isdominated by Gurung and other ethnic groups. The area is also for temporary sheds (goths) forlivestock. There is a tradition to leave buffaloes temporarily in the higher pasture called Lek andbring them back to the village once they begin milking (Upadhyay 2012).

3.2 Biophysical Setting

The lower belt of Bhadaure Tamagi VDC is dominant as settlement and agriculture land usewhereas the upper one is used for forests, grazing land and protected system. As Panchase isa protected forest and pilgrimage site, almost all upper areas are under protection (GoN 2012a).As the Panchase forest represents a relic of extensive forests, it is necessary that conservationefforts are made to ensure its survival. Both lowland and upperland of the VDC are under pressureof invasive species. The forests and unattended lands at higher elevations were covered by anuisance weed, banmara (Eupatorium adenophorum), whereas the lower part was used forsettlements and agriculture purposes, and this part was heavily invaded by Ageratum conyzoides.As the lower part of the VDC is an entry point from Pokhara Sub-metropolis, it is at high risk ofalien species introduction while bringing goods and commodities for livelihood.

3.3 Climate

Both maximum and minimum temperatures were plotted against a period and they were foundincreasing over thirty years; however, their trend was gradual. Average maximum and minimumtemperatures at Lumle were 20.22 0C and 11.99 0C respectively (Table 3). Precipitation inBhadaure Tamagi VDC was erratic and increasing in trend with some extremes (Figure 5). Theaverage precipitation was 5723.8 mm per annum. Maximum precipitation was recorded in 1995and extreme maximum in 1998. The lowest annual precipitation was recorded in 2006 (4162mm) during a period of thirty years. This variation in precipitation within a decade may beassociated with climate change (Annex 3, 4).

Table 3: Temperature characteristics of Lumle, a nearby station of Bhadaure Tamagi VDC


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3.4 Biodiversity

The Panchase area is rich in biodiversity (Koirala 1998), possessing a total of 589 floweringplants including 107 NTFPs (Bhattarai et al. 2012) and 113 orchids (Subedi et al. 2007) includingthree endemic and three threatened species (Subedi et al. 2011). In the present assessment, atotal of 140 plant species were recorded from a 10-day field visit to Bhadaure Tamagi VDC,including threatened species like tree fern (Cythea spinulosa), bhyakur (Dioscorea species)and orchid (CITES II species) (Figure 6) (Annex 5). All these threatened plants are on the vergeof collapse due to invasion of alien plant species and anthropogenic disturbances; deforestationand open free grazing. According to Pimentel et al. (2000), about 42 percent of the threatenedor endangered species are at risk primarily due to alien species.

Figure 5: Temperature and precipitation at Lumle station, close to Bhadaure Tamagi VDC


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3.5 Invasive Alien Plant Species

There are 100 worst weed species in the world (Lowe et al. 2000), among them eleven worstinvasive alien species are found in Nepal. Of the seven important alien invasive species for theAsia Pacific region, all are pertinent to Nepal and six species except Mikania are found in thePanchase area. Among the 14 worst species, nine species were prevalent in Bhadaure TamagiVDC, Panchase (Table 4), and Ageratum and Ageratina were the most problematic.

A note of 166 alien invasive plants species of Nepal was made by IUCN, Nepal in 2005 (Tiwariet al. 2005); however, in a pursuit of changing climate, the list was outnumbered. The present

Table 4: Worst IAS and their frequency in Nepal and Panchase

Figure 6: A threatened plant species Cythea spinulosa (tree fern) at Tamagi and orchids at Harpan,Panchase


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study compiled literature, updated the list and catalogued it into 194 for Nepal (Annex 6). Out of194 invasive species 52 were recorded from the VDC, some of them highly invasive and othersless invasive. There were 18 highly invasive plant species in and around the Panchase area,but local communities were aware of the impact of only nine of them (Annex 6). The communitiesneed better management to controlling such pants. There were 12 competitor invasive speciesestablished in the VDC, but they have not spread aggressively in the area at present but arelikely to spread and invade aggressively unless management is immediately strengthened. Therewere 22 invasive species introduced in the area and are likely to establish if management ispoor. Among the nine highly invasive alien species recognized by the local communities, Ageratumconyzoides and Ageratina adenophora were more frequent and dense in distribution (Table 5)and severe in possessing detrimental impacts to livelihood and biodiversity. They were notedfor massive invasion and fast spread in Bhadaure Tamagi VDC.

3.6 Invasive Alien Plant Species: Ageratum conyzoides andAgeratina adenophora

3.6.1 Profile of selected species

3.6.1.1 Ageratum conyzoides

Taxon name: Ageratum conyzoides L.Synonyms: Ageratum album Willd. Ex Steud., A. caeruleum Hort. ex. Poir., A. caeruleum Desf.,A. conyzoides var hirtum (Lam.) DC., A. cordifolium Roxb., A. hirsutum Lam., A. hirtum Lam., A.humile Salisb., A. latifolium Car., A. maritimum H.B.K., A. mexicanum Sims., A. nanum Hort. ExSch. Bip., A. obtusifolium Lam., A. odoratum Vilm., A. suffruiticosum Regal, Cacalia mentrastoVell.Family : Asteraceae (Compositae)Common names: Ageratum, Billy-goat weed, Blue ageratum, Blue flowered groundsel, Bluetop, Chick weed, Goat weed, Invading ageratum, White weed, Winter weed.Local names: Gandhe, Nilo gandhe, Raunne, Hanumane, Paino (Gurung), Jhang noniba(Tamang), Jhorijhyang (Tharu).Local name in Bhadaure Tamagi VDC: Gandhe, Nilo gandhe, Maobadi jhar and Paino.First report in Nepal: Burkill in Rec. Bot. Ind. 4:114.1910; Nepalgunj, 25.10.1972, N.P.Manandhar 9857 (KATH).

Description: A. conyzoides is an annual erect, branching, soft, slightly aromatic hispid herbwith shallow, fribrous roots. It grows up to 1 m tall. Stems and leaves are covered with fine whitehairs; the leaves are egg-shaped with broad end at base up to 7.5 cm long. The flowers arepurple, blue, pinkish or white, < 6 mm across, with around 30-50 flowers, arranged in closeterminal flower-heads. Fruits are small brown one-seeded achene. The roots and rootlets aredensely fibrous and branched and tightly anchored the soil.

Habitat: A. conyzoides commonly grows in the proximity of habitation, thrives in any gardenand agricultural soils, and is very common in disturbed sites and degraded areas. It invadesforests, woodlands, grasslands, cultivated lands, and banks of water courses. It is an importantweed of plantation crops and overgrazed pastures.

Reproduction and dispersal: This species reproduces mainly by seeds, which are dispersedon the hairs of livestock and wild animals, clothes and agricultural machinery. It can complete itslife cycle (germination to flowering) in less than two months. The plant flowers almost throughoutthe year, precisely from June to March. The seeds germinate in response to light (photoblastic)and are often no longer viable within 12 months. Ageratum conyzoides is sometimes confused


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with Ageratum houstonianum (blue billy-goat weed). It can be distinguished as follows by only afew hairs on the bracts surrounding its flower-heads (the involucral bracts are glabrous or sparselypubescent). Each of the tiny flowers/florets (make up the flower-heads) has two long and narrowprojections that are about 5 mm long. The bases of the flower-heads are relatively large (5-8mm across).

Distribution: It is native to Central and South America and the West Indies. In Nepal, it isdistributed throughout the country from 75 to 2000 masl.

In Bhadaure Tamagi VDC, A. conyzoides was observed in wards no. 1, 4,5,6,7 and 8, i.e. it wasrecorded from Bhadaure, Harpan, Chainpur, Damdame, Kutmidanda and Sidane at altitudesbetween 821 m and 1699 m (Table 5), but its availability above 1400 m was low and above 1700m nil. A. conyzoides was most dense in Kutmidanda, Harpan and Chainpur (Figure 7) and mostfrequent in Kutmidanda, Harpan and Thulakhet. In particular, the abandoned agricultural fieldsof Harpan, Chainpur, Kutmidanda and Thulakhet were severely invaded by Ageratum. The leastmanaged or unattended agricultural fields with moisture and partial shade were favourable forthe growth and spread of A. conyzoides (Figure 8).

Ageratum houstonianum Mill.It is common in barren fields in association with A. conyzoidesLinn. It has numerous sticky hairs on bracts surrounding its flower-heads. The invulucral bracts are hairy and glandular and differfrom those of Ageratum conyzoides. Each of the tiny flowers/florets which makes up the flower-heads has two short andnarrow projections that are about 1-2 mm long. The bases of theflower-heads are relatively small (3-6 mm across).

Figure 7: Distribution of A. conyzoides in Bhadaure Tamagi VDC


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3.6.1.2 Ageratina adenophora

Taxon name: Ageratina adenophora (Spreng.) R.M. King and H. Rob.Synonyms: Eupatorium adenophorum Spreng., E. glandulosum Kunth.Family: Asteraceae (Compositae)Common names: Crofton weed, Hemp agrimony, Mexican devil, Sticky agrimony, Stickyeupatorium, Sticky snake root, White thoroughwortLocal names: Kalo banmara, Kalimunte, Mohini (Chepang), Thangpa maran (Tamang).Local name in Bhadaure-Tamagi VDC: Banmara, Banmasa, Kalo banmara, Kangres jhar.First report in Nepal: Banerji in J. Bomb. Nat. Hist. Soc. 55: 259.1958 (E. glandulosum); Manichurforest, 2134 m, 28.03.1961, P.N. Suwal & Party (KATH)

Description: A long-lived erect, tufty, semi-shrubby, perennial herbaceous plant of about 1–2 mtall, but sometimes attains up to 3 m. It produces numerous upright stems from a woody rootstock.The branched stems are densely covered in sticky hairs when young and may be green, reddishor purplish. They become slightly woody and turn brownish-green or brown when mature. Leavesare diamond-shaped rhomboid or almost triangular and oppositely arranged along the stems.They have sharply pointed tips and are mostly hairless, but their stalks are often covered insticky hairs. The leaf blades 4-15 cm long and 3-9 cm wide are diamond-shaped with bluntlytoothed margins.

Small white flower-heads consist of several tiny flowers surrounded by two rows of greenishbracts 3-5 mm long. These flower-heads (5-8 mm across) are borne in large numbers andarranged in clusters at the tips of the branches in terminal corymbose iflorescense. The seedsare slender, reddish-brown or blackish-brown, and slightly curved. These ‘seeds’ (1-2 mm longand 0.3-0.5 mm wide) have four or five slight ribs which run length-wise (longitudinally) and theirbodies are hairless. However, they are topped with a ring pappus of numerous whitish hairs (3-4 mm long), which are readily shed. Its roots are yellowish and give off a distinct carrot-like smellwhen broken or damaged.

Habitat: It is a weed of roadsides, pastures, fence-lines, disturbed sites, and banks of watercourses in subtropical and warmer temperate regions. It is also commonly found in openwoodlands, forest margins and forest clearings. It prefers a warm and wet environment, but itsability to adapt to wide environmental conditions is very strong. It can grow in environments withtemperature ranges from 5°C to 42°C. It grows on dry and barren hills, and can even grow incracks in stone walls, road edges and houses. It also grows more vigorously in a fecund soilwith moisture. It has a shallow rooting system spreading horizontally in the top soil.

Reproduction and dispersal: A. adenophora propagates by seed, with each plant producing30,000–45,000 seeds, and sometimes as many as 100,000 seeds (Jianghua 2005). It maintains

Figure 8: A. conyzoides, a weed is dominating agriculture fields when they are less nurtured


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and spreads its population along rivers and roads, mainly by means of its seeds. Wind, flowingwater, vehicles, people and livestock are mediums for spread. Seed germination requires light,but its seedlings can grow in shady environments, which is an advantage to its invasivenessinto other plant communities. It can also reproduce by asexual reproduction through adventitiousroots.

Distribution: It is native to Mexico and possibly Central America, although it is now distributedwidely in the United States, Australia, New Zealand and many countries of south-east Asia. Itwas introduced in India after 1948 (Biswas 1934) and it is likely that it was introduced in Nepalfrom India through eastern border (Banerji 1958) for agricultural purposes probably before 1950.It is expected to spread at the rate of 20 km per year (Jianghua 2005).

In Bhadaure Tamagi, it was observed throughout the VDC except Kutmidanda. The Kutmidandaarea was heavily populated by Ageratum conyzoides and may be due to its suppression, A.adenophora could not compete and sustain in the area. It was also most frequent in Harpan(1214-1241 m), Thulakhet (920-929 m), and areas above 1400 m. Deurali, Chisapani, Bhanjyang,Ahaldada were most for frequency and Chainpur, Tamagi, Sidane and Harpan for density of thespecies. As Ageratina is found up to 2500 m elevation (Kunwar 2003), the transition landsbetween agriculture and forests, fallow lands and road sides above 2000 m of Bhadaure TamagiVDC are likely to be invaded, if prompt preventive and controlling measures are not in place.

Figure 9: Distribution of A.adenophora in Bhadaure Tamagi

Figure 10: A. adenophora growingalong the edges of roads, canals,rivers and ponds


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Chromolaena odorata (seto banmara)

Chromolaena odorata, Siam weed, a fast-growing perennial shrub, native to South America and CentralAmerica, has spread widely in the last 150 years into the tropical regions of Asia, Africa and the Pacific(Gautier 1992). The first report of the plant was noted in Nepal by D.Don in his Prodromus Florae Napalensis(Don 1826) and its voucher specimen was collected in 1964. It forms dense stands that prevent theestablishment of other plant species. It is an aggressive competitor and may have allelopathic effects. It isalso a nuisance weed in agricultural land, commercial plantations, road sides and forest edges.

Chromolaena odorata is a large upright shrubby plant 1.5-5 m tall with relatively broad, egg-shaped withbroad end at base or triangular leaves and young stems that are sparsely covered in fine hairs. Its seedsare relatively large (4-5 mm long), and are topped with a ring pappus of whitish or brownish hairs (about 5mm long). It is a tropical weed and found between 75 and 1540 m (Tiwari et al. 2005). In Bhadaure TamagiVDC, it has been introduced in Ghatichina, 820 m, lower elevation of the VDC. Very few scattered patchescan be seen along the river edges, agricultural fields and road sides. It is well grown in sunny, open andwell drained areas such as forest margins, fallow lands and roadsides whereas the A. adenophora (kalo

banmara) prefers moisture and wetlands and swamps for its growth. It is a typical pioneer species ofsecondary forest succession with a strong heliophilic character and vigorous vegetative development(Hoevers and Mboob 1996). It requires disturbances to native vegetation in order to become established.Shoots start rooting once in contact with ground. C. odorata is entomophilous and yields a mass of light-weight seeds that are easily dispersed by wind courtesy of the aviation of a buoyant pappus. The fruitshave hooks and could be transported to other locations by sticking to the bodies of fauna and to farmmachinery (Adebayo and Uyi 2010). It flowers between December and April. Sexual reproduction startswhen the plant is one year old. Seed production is prolific and reported up to 87,000 seeds per matureplant (www.issg.org/database).

It easily invades disturbed habitats and smothers native plant stands. It reduces species diversity both dueto competition and allelopathic effects (Ambika and Jayachandra 1980). Its foliage is reportedly flammable(contains essential oil), making it a threat to indigenous species which are not resilient to forest fire (Witkowskiand Wilson 2001). It also affects the nesting sites of crocodiles (Pant and Sharma 2011). However, itsleaves contain insect repellent compounds, and root exudates may have nematocidal effects, resulting inbetter yields of maize and ground-nut (Hoevers and Mboob 1993). It is, however, obvious that with itsabundant biomass production, C. odorata contributes significantly to the build up of organic matter andsubstantial amount of nutrient-rich litter to the soil and improving chemical and physical properties of soil(Lucas 1989). C. odorata also inhibits the development of another IAS Imperata cylindrica (Bani and Gall1996).Smoke from C. odorata repels mosquitoes (Yehouenou 1996).

C.odorata can be effectively reduced by burning and weeding. Chemical control by using herbicides (e.g.triclopyr) may be effective, but it is impracticable, expensive and counter-productive to environment. Biologicalcontrol is possible by introduction of natural enemies, arctiid moth, Pareuchaetes pseudoinsulata. It effectivelydefoliates pure stands, but it is less successful in scattered patches. Other natural enemies, the fliesCecidochares connexa, Aphis gossypii, A. citricola, Homona coffeariahave also been identified as potentialbiological control agents of Siam weed (Kluge 1989, Muniappan and Nandwani 2002). In Srilanka, Tephrosiapurpurea was introduced to control C. odorata (Ooi et al. 1988). Plantation of Brachiaria decumbens Stapfcv. Basilisk (Signal grass) and legumes as biological control on a large scale could considerably reduce theChromolaena in pastures (Wu and Xuejun 1991, Wu et al. 1996).


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3.6.2 Diversity and distribution

Of the 13 sampling sites, they were categorized into two zones as 800-1400 m asl and 1400-2100 m asl. There were five sites within 800-1400 m asl, six within 1400-2100 m asl and twowere mixed or overlapped within 1200-1600 m asl. The sites at lower elevation i.e. 800-1400 masl were co-invaded by Ageratum and Ageratina species except at Kutmidanda. A. conyzoideswas found in Bhadaure at the least extent. Based on frequency, density and importance value ofboth IAS, importance value index was highest for lowlands six sites: Harpan (1214-1441 m),Chainpur (1036-1136 m), Kutmidanda (1337-1361 m), Thulakhet (920-929 m), Sidhane (1326-1690 m) and Ghatichina (821-975 m). Therefore, the lowland areas of the VDC were moresusceptible to biological invasion. The lowland sites Kutmidanda, Harpan, Chainpur, Thulakhetand Ghatichina were more susceptible to Ageratum invasion.

Table 5: Density and frequency of the selected IAS (A. conyzoides and A. adenophora)

Figure 11: Importance Value Index of IAS in Bhadaure Tamagi VDC, Panchase


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A. adenophora was homogeneous in distribution throughout the VDC except Kutmidanda, andthe ecosystems of Chainpur (1036-1136 m), Tamaghi (1440-1908 m), Harpan (1214-1441 m),Chisapani (2058-2063 m) and Sidane (1326-1690 m) were compounded by invasion of A.adenophora. It was most successful in invading sites above 1400 m but in lower sites, it wasrivaled by A. conyzoides and the lower sites were co-invaded by both species. Five sites above1400 m: Ahaldada (1860-2096 m), Deurali (1410-1822 m), Bhadaure (1502-1699 m), Bhanjyang(2001-2048 m) and Chisapani (2058-2063 m) were the least affected.

3.6.3 Potential invasion

Abandoned agricultural lands and grazing lands of Bhadaure Tamagi were quite refuge forAgeratina adenophora and Ageratum conyzoides. Ageratum conyzoides was a common weedin all crops apart from those under deep shade. It is also a first species to colonize in degradedareas and so able to prevent other plants from establishing.Grazing land was the most vulnerableto both Ageratum and Ageratina species invasion because it was frequently browsed by bothdomestic livestock and wild animals. The grazing lands, fallow lands and roadsides are lessnurtured for personal use. Therefore, the areas are more prone to biological invasion. Cattlegrazing and trampling has allowed more invasive alien species to take root. Ageratina adenophorahas colonised forest margins, stream banks, road sides, fallow lands and disturbed areas,preferring shaded and wetter areas but also growing in open sunny sites. It was luxuriant indamp areas such as wetland margins, drainage lines, gullies and in clearings in wetter forests.Fallow lands: roadsides, uncultivated lands, disturbed grasslands, and marginal lands of forestsare favourable for colonisation of invasive alien species. Therefore, unless the existing landmanagement system is strengthened, IAS are likely to be introduced and established in otherareas of the VDC. Following the GIS and habitat suitability mapping, the following areas werefound more susceptible to invasion of A. conyzoides and A. adenophora.

Table 6: Potential invasion map


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Figure 12: Invasion maps for A. conyzoides, A. adenophora and both species


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3.6.4 Characteristics of invasive alien species

Common characteristics of IAS include rapid reproduction and growth, high dispersal ability,phenotypic plasticity (ability to adapt physiologically to new conditions), and ability to survive onvarious food types and in a wide range of environmental conditions, etc. Invasive alien speciesdisplay strong vegetative growth, abundant seed production capacity, high seed germinationrate, long-lived seeds, rapid maturation of a sexually reproductive stage and high ability toestablish over large areas. The alien species are too abundant and dominant even in poor soiland disruptive to the other native species reducing their variability. Some characteristic featuresof IAS are as follows:

• They grow rapidly and reach maturity early.

• Many species are capable of vegetative reproduction via stolon (e.g.Alternanthera philoxeroides and Eichhornia crissepes), rhizomes, bulbs (e.g.Oxalis latifolia) and rooting at the tips of stem (e.g. Ipomoea carne and Mikaniamicrantha) and root fragments (e.g. Ageratina adenophora, Ageratumconyzoides and Chromolaena odorata).

• They are highly adapted to wind and insect pollination.

• Their seeds get widely dispersed by winds, water, birds and other means,enabling them to colonise in new areas at distances far from their original home.

• They often have a different phenology for leafing to dormant stages that providebetter opportunities to take nutrients from soil.

• They usually are not attacked by parasites, diseases, herbivores, etc. in thenewly introduced area.

Figure 13: Characteristics of invasive alien species


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3.6.5 Mechanism of invasion

Absence of predators and parasites in alien habitat helps in advancing invasive alien species,otherwise IAS are under control in native habitat. It is supported by the Enemy Release Hypothesis(ERH) - the idea that species are more likely to become invasive when they are free from theirnatural enemies (Torchin et al. 2003). The Biotic Resistance Hypothesis (BRH) argues thatdiverse communities, particularly forests, are highly competitive and readily resist invasionbecause of interactions with native species, including natural enemies, limit invaders’ impacts(Darwin 1859, Maron and Vila 2001). As a result, forests, which are more diverse than any otherecosystem are resistant to ecological invasion (Pimm 1984); however, the dense forest withmonospecific stands are vulnerable to biological invasion. The success of invasive alien plantsis also due to their allelopathic competitive strategy - Novel Weapon Hypothesis (NWH) (Raiand Tripathi 1982).

The biological invasion usually follows a sequence beginning with introduction, progressing toestablishment and culminates into spread and invasion (Figure 14) (Keam et al. 2009). Not allintroduced species are invasive. Rule of Ten suggests that only 10 per cent of introduced specieswill survive and 10 per cent of them will become established. Among the established aliens,only 10 per cent will spread and become invasive over time (Keam et al. 2009). So, as a rule ofthumb, about 1 per cent of introductions is likely to become invasive (Williamson 1996).

3.6.6 Causes of invasion

Determinants of plant invasiveness per se are extremely complex (Rejmanek et al. 2005).Anthropogenic and natural factors act together to facilitate the introduction and spread of alienspecies. The consensus of local communities on the causes and factors of invasion/spread wason biology of invasive plants and their adaptability, land use management and seed dispersal bybiotic and abiotic factors (Table 7).

Major causes of spread and invasion of alien species observed by local communities weremodes of plant reproduction, large number of seed production, plant allelopathy, etc. as bioticfactors and wind dispersal mechanism, land use change, depopulation, road and transportation,etc. were abiotic factors. Small seeds, wind dispersal, plant with high competitive ability, etc. areother important factors that accelerate plant introduction and establishment. Roads function asprime corridors for establishment and spread of invasive plant species. Marginal land areas,especially fallow agricultural fields, became source pools for new infestations and spread. Landfragmentation and degradation also helps in enabling the spread of invasive aliens. Availabilityof moisture and dispersal of propagules by water helps to increase plant introduction,

Figure 14: Mechanism of invasion of IAS


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establishment and spread. According to Pysek and Prach (1994), soil moisture and water coursesare complementary to IAS invasion. Many invasive plant species release chemical compoundsinto the environment, which are not generally harmful to them, but those chemicals suppressthe growth of other plants growing in close proximity of invasive species. This negative effect(often referred to as allelopathic effect) of invaders on the native species confers a tremendouscompetitive advantage.

Land degradation and low productivity were major factors leading to depopulation of the VDC.The migrated people are likely to bring desirable crops, domestic animals, and ornamentalspecies to their new homes, potentially speeding dispersal of new non-native species to otherareas. According to Reiter (2001), population migration, increases in density, as well as poorsanitary conditions induce spread of invasive species and diseases. Less care about use ofseeds, fertilizers, land and soil fertility and un-routinely control of weeds and invasive aliens ledto rampant spread of invasive aliens. High nitrogen levels provide an advantage to invasivespecies (Brooks 2003).

3.6.7 Invasion trend of alien species

Impact of invasive alien plant species was apparent for over a period of three decades in BhadaureTamagi VDC when salah jhar (Conyza japonica) was problematic about 25 years ago. Accordingto local communities, Conyza, Phalaris, Borreria, Ageratina, Ageratum and Chromolaena areconsecutively invading the VDC and Panchase. Agricultural land was first worsened by Conyzaand was exacerbated by invasion of Phalaris minor. Later, Borreria was established and menacedagricultural productivity. Roadsides, forests and agricultural periphery close to wetlands, ponds,streams, and wells were invaded by Ageratina about 15 years ago and its impact is still increasing(Figure 15).

Figure 15: History of introduction of invasive alien plant species in Bhadaure Tamagi VDC

Table 7: Causes and factors for invasion (N = 28)


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In household surveys and group discussions, Damdame and Chainpur/Harpan areas wereidentified as the first introductory points for Ageratum and Andherikhola and Chiandanda forAgeratina. Other probable areas of introductions are given in Table 6. There were 9.32 Ageratinastands/m2 in Hemja and Lahachok VDCs of Kaski district in 2005 (Kunwar and Uprety 2005),but in 2012 in the Bhadaure Tamagi area, it was about 11.49/m2. Despite their insisting invasion,they have been emaciated in agricultural fields because of aggressive invasion of A.conyzoides.Agricultural fields and even roadsides are being invaded by A. conyzoides and it is now being aserious menace to agricultural production and local biodiversity. Since 5 to 7 years, all theunattended fields, farm plots and adjoining areas with inadequate nurture have been intrudedby A. conyzoides.

Chromolaena odorata (seto banmara) is being introduced in open sunny and well-drainedareas such as forest margins, fallow lands and roadsides of lowlands of Panchase.Therefore,invasive aliens are increasing over time in the Panchase area. The area was assaulted byAgeratina adenophora at higher elevations and forest fringes, by Ageratum conyzoides at midelevations and agricultural systems, and by Chromolaena odorata at lower elevations androadsides and fallow lands. Local communities think that the increasing invasion of alien specieswas likely due to less land management interventions and increasing temperature.

3.6.8 Impacts of invasive species

Invasive alien species threaten the environment, economies, and human welfare (Lodge et al.2006). They reduce biodiversity, replace economically important plant species and increase theinvestment in agriculture and silviculture (Ricchardi et al. 2000), disrupt prevailing vegetationdynamics and alter nutrient cycling (Richardson 1998). They can promote fire and alter waterand nutrient availability. They have a major impact on catchment hydrology; 30 to70 per cent oflower water runoff is reported from watershed areas with dense stands of alien species(Geldenhuys 1986). Plant invasions dramatically affect the distribution, abundance andreproduction of many native species (Sala et al. 1999). Therefore, impacts of invasive alienspecies are immense, insidious and irreversible (Mcneely 2000).

Impacts of invasive alien plant species A. conyzoides and A. adenophora were well observedthroughout Bhadaure Tamagi VDC and none of the ecosystems was free from this menace.Edges of forests, agricultural lands and wetlands were severe in IAS intrusion. As a result ofinvasion, socio-economic impacts were more apparent. Despite a number of impacts of IAS

Table 8: Information about the first sight of IAS in the Panchase area by local communities (N =28)


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have been witnessed, a detailed species specific impact assessment for each habitat andecosystem is yet to be carried out.

3.6.8.1 Biodiversity threats

The transport of organisms through increased levels of travel, trade and tourism is leading tothe widespread breaching of natural biogeographic barriers at unprecedented rates.Consequences can be severe, especially in naturally isolated ecosystems. The ecosystemsparticularly forests, wetlands and grazing lands of the VDC were deteriorated due to invasion ofalien species. Species such as Artemisia, Solanum xanthocarpum and Urtica sp. of fallow landsand banso, samo, phurke, mallido, siru, etc of agricultural lands were threatened by invasivealien speies in Bhadaure Tamagi VDC. Again, IAS are also considered as biological polluters(Westbrook’s 1991) and are capable of hybridising with native plant relatives that result inunnatural changes to a plant’s genetic make-up. Therefore, the biodiversity of Bhadaure TamagiVDC is in great peril because of IAS.

3.6.8.2 Impacts at ecosystem level

Although all ecosystems are susceptible to invasion, the ecosystems intertwined with higherlevel of human interventions (Yan et al. 2001) (eg forestry, agriculture, grazing lands) are likelyto pose greater susceptibility. In Bhadaure Tamagi VDC, grazing, agriculture and fallow landsand road sides were highly susceptible to invasion (Figure 16). In these productive ecosystems,fast growing opportunistic alien species more benefited because of their mode of reproductionand greater adaptability.

Abandoned agricultural lands and grazing lands of Bhadaure Tamagi were a refuge for Ageratinaadenophora and Ageratum conyzoides. A. conyzoides was a common weed in all crops apartfrom those under deep shade. It is also a first species to colonise in degraded areas and so ableto prevent other plants from establishing. Ageratum reproduces mainly by seeds, which are

Figure 16: Impact of IAS on different habitats


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dispersed by livestock, clothes and agricultural machinery. It can complete its life cycle(germination to flowering) in less than two months, compounding the agro-ecosystems byproduction of outnumbered propagules. Its competitive ability has impacts on native biodiversityand it is also poisonous. It was considered as low risk posed species by Tiwari et al. (2005);however, in Bhadaure Tamagi VDC, it was one of the serious menaces for agricultural fields. Itwas introduced about 7 years ago in Bhadaure Tamagi VDC and has aggressively spread inagricultural fields because of application of excessive nitrogen chemical fertilizer, according tolocal communities.

Grazing land was the most vulnerable to both Ageratum and Ageratina species invasion becauseit was frequently browsed by both domestic livestock and wild animals. Again, the grazing landsof the VDC at higher elevations have open access (Upadhyay 2012) and management carefrom government, community and individual levels is almost insignificant. The grazing lands,fallow lands and roadsides are less nurtured for personal use. Therefore, the areas are moreprone to biological invasion. Cattle grazing and trampling has allowed more invasive alien totake root (NEPA 1998).

Forests of Bhadaure Tamagi VDC were least affected by invasive alien species (Figure 16) asthey are more diverse (Bhattarai et al. 2011) and close canopied. Invasive alien species areshaded out by trees and lianas in forests (Rouw 1996) and their invasion is slowed down(Tjitrosemito 1996). As a result, dense and diverse forests are more resistant to ecologicalinvasion (Pimm 1984).

However, forest edges and plantation/secondary forests were disturbed by invasive species.The plantation forests of Ranibas of Paudur VDC and Peribasti of Bhadaure Tamagi VDC wereconsidered as the first entry points of Ageratina adenophora. It has colonised forest margins,stream banks, road sides, fallow lands and disturbed areas, preferring shaded and wetter areasbut also growing in open sunny sites. It was luxuriant in damp areas such as wetland margins,drainage lines, gullies and in clearings in wetter forests. It grows in large dense clumps and willeventually outcompete all other plants in an area, choking out native vegetation and forming amonoculture. Therefore, grazing lands, roadsides, disturbed forests and wetlands of BhadaureTamagi VDC are common niches of A. adenophora. Expansion of IAS into forest ecosystems ofNepal in last few decades has posed a serious threat to forest health with a possible impact oncarbon balance (GoN 2011a).

Fallow lands, roadsides, uncultivated lands, disturbed grasslands, and marginal lands of forestsare favorable for colonisation of invasive alien species. Other potential invasive competitorssuch as Parthenium hysterophorus, Lantana camara, Chromolaena odorata, Cassia tora, etcare likely to invade Bhadaure Tamagi VDC unless the existing land management system isstrengthened because they are easily introduced in fallow lands. Other invasive aliens of Nepalare Mikania mikrantha, Bidens pilosa, Amaranthus viridis, A. spinosus, C. sophera, etc whichcan alter the species composition of fallow and cultivated lands (NBS 2002).

3.6.8.3 Impact on soil

Invasion by alien plant species affects the dynamics and composition of soil and have impact onecosystem functions such as soil nutrient cycling (Yelenik et al. 2007), hydrological flows andsoil chemistry (Randall and Marinelli 1996). With abundant biomass production, Ageratinaadenophora also contributes positively to build up the soil organic matter and soil pH (Hoeversand Mboob 1996), but analysis of biomass of Ageratina and soil pH was not in the scope of thepresent study

In Bhadaure Tamagi VDC, invasive alien species (A. conyzoides and A. adenophora) weregrowing in a wide range of soils but not flourishing in shade. At the land use level, Ageratumwas common in agricultural fields and Ageratina in fallow lands and roadsides. Soil texture


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analysis of soil samples of fallow lands and cultivated lands showed that coarse sand washighest in cultivated fields and gravel in fallow lands (Table 9). Silt clay was higher in cultivatedfields. Since cultivated fields and barren/fallow lands were heavily invaded by Ageratum andAgeratina respectively, physical soil data of these two sites did not reveal significant relationship.However, all types of soil even gravel to fecund were supportive to establishment of Ageratina.Therefore, their diversity and distribution were homogenous throughout the VDC. Ageratinawas well grown in dry and barren hills, and even in cracks of roads, stone walls and houses.

Ageratum conyzoides were common in the proximity of habitation and gardens and introductionand establishment of Ageratum could be supported by more silt and clay of the soil of thesehabitats. The agricultural fields with adequate soil moisture and partial shade were favorable forgrowth of Ageratum but closed canopy was even lethal to seedlings. The sites (Chainpur,Kutmidada) with highest density and frequency of A. conyzoides were also possessing highestsoil moisture content (Table 10). The areas were also possessing highest soil pH.

The correlation study between altitude and soil characters and plant IVI was negative. Soil pH,soil moisture, and IVI of both IAS were negative to altitude (Table 11). Whereas, IVI of IAS waspositively correlated to soil pH and moisture, as soil moisture enhances introduction of IAS.

Table 9: Physical characteristics of soil of Bhadaure Tamagi VDC

Table 10: Chemical characteristics of soil of Bhadaure Tamagi VDC

Table 11: Correlation analysis among soil characters, altitude and IVI of A. conyzoides and A.adenophora


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Damp areas such as wetland margins, drainage lines and gullies densely covered by Ageratinashowed that Ageratina favors soil moisture for establishment. Availability of moisture and thedispersal of propagules by water may increase establishment of Ageratum and Ageratina alongthe water courses. As lowlands of the VDC have been exploited for agricultural production,applications of chemical fertilizer were common resulting in increment in soil pH and IAS. SoilpH was negatively correlated to altitude and it was positive to IAS importance value.

3.6.8.4 Impacts at species level

Household survey revealed that roadsides and fallow lands previously dominated by Artemisia,Solanum, Urtica, etc. have now been invaded by aliens. Artemisia, Solanum and Urtica becamefail to maintain their biomass in the changing climate and their dominance was fairly slacked offby invasive alien species particularly Ageratina. Ageratina contains cadinene sesquiterpeneswhich plays a role of allelopathy and control associated vegetation. It is also poisonous to horses(Bohlmann and Gupta 1981, Baruah et al. 1994). Similarly in agricultural fields, invasive alienspecies precisely Ageratum conyzoides, Borreriaalata, Phalaris minor, etc. were known to replacethe native species as well as prevent their natural regeneration. The grasses such as Banso,Samo, Phurke, Mallido and Siru etc. have been threatened because of invasion of A. conyzoides,Borreriaalata, Phalaris minor in agriculture fields (Table 12).

3.6.8.5 Impacts at socio-economic level

Lower area of Bhadaure-Tamagi VDC is densely populated by subsistence farmers and livestockrearing is an integral part of their livelihood (Bhattarai et al. 2012). As livestock comprises amajor part of agro-ecological system of Panchase, fodder collection is the second most importantbiomass outtake, especially in dry and lean periods when on-farm fodder is particularly sparse.Preferred species for lopping fodder were Brassiopsis heinla, Ficus lacoor, F. glaberrima, F.hispida, Streblus asper, Eurya accuminata, Prunus species, Quercus lamellosa and Q.semecarpifolia (Bhattarai et al. 2012), however, their productivity was constrained by Ageratinaand Ageratum by outcompeting for nutrients. Livestock rearing was possible by stall-feedingand foraging at lower elevation and by free grazing at upper area.

Upper area of the VDC is dominated by Gurung and other ethnic groups and their livelihooddiffers to inhabitants of lower area. Out-migration is one of the characteristics of the VDC and itis more common in upper part of VDC. Again the Gurung households of upper part of the VDC

Table 12: Impact of invasive alien species at species level


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have been allured for abroad and cities for various reasons, resulting in depopulation in theVDC. The outcome of out-migration has multi-folds; agricultural fields are laid fallow, lack oflabor (Maren et al. 2013) and decreased productivity. All these factors are inherent to spread ofinvasive aliens. Out-migration is less extensive in lower areas where Brahmin and Kshetri aredominant because these ethnic groups are less eligible for Gurkha recruitment (Maren et al.2013). Three limiting factors to agricultural production in Bhadaure Tamagi VDC are namelylabour, water and fertilizer (Thapa 1996). Inadequate labor in the VDC led the agriculture andgrasslands less nurtured and unattended, resulting in rampant spread of invasive species.

3.6.8.5.1 Negative impacts

Present study found that invasive species have deleterious effects to socio-economy in BhadaureTamagi VDC. The current livelihood pattern amplified introduction of non-native species becauseof more interest towards off-farm activities, less care about seeds, fertilizers, land and soil fertilityand untimely control of weeds and invasive aliens of farmlands. As a consequence, farmers ofBhadaure Tamagi VDC are plagued by invasive weeds and lost their properties.

As the species abrades agricultural crops, negative impacts to livelihood are apparent. Accordingto the local communities, A. conyzoides is more harmful to the local livelihood and biodiversitythan A. adenophora (Table 12). Neither cattle nor goats eat Ageratum, and areas traditionallyused for grazing in Tamagi area of the VDC were deteriorated, forcing villagers to walk farther insearch of grazing pastures. The increased time spent on this activity translates into a substantialeconomic loss. Incidences of livestock mortality were common in village because of accidentalconsumption of Ageratum and its flowers by livestock particularly cows and buffaloes whilefeeding other grasses. In last five years, there were three casualties of livestock mortality only inHarpan, Bhadaure Tamagi VDC.

Figure 17: A house owned by a Gurung left unattendedfor long at Tamagi, Bhadaure Tamagi VDC

Morbidity and mortality of livestock by A. conyzoides (Nilo gandhe)Impact of A. conyzoides is more severe in Harpan, Chainpur and Kutmidada of Bhadaure Tamagi VDC. There are a number ofimpacts of by A. conyzoides, but the cases of livestock mortality particularly of buffalo in Harpan – 4, Bhadaure Tamagi VDCwere noticeable. In last five years, there were three cases of livestock mortality in Harpan and two cases in Chainpur. In allcases five buffaloes were assailed.

Mr. Uma Lal Poudel, Mr. Nar B Khatri and Mrs. Vishnu K Khatri of Harpan – 4 and Mr. Deepak Parajuli and Mr. Tek B Sunar ofChainpur – 5, Bhadaure Tamagi VDC got lost their buffaloes because of feeding A. conyzoides by their buffaloes. In general,buffalo and other livestock except goat did not forage A. conyzoides but in sometimes, they inadvertently feed A. conyzoideswhile feeding other grasses. The cases were generally happened in spring season when the plant flowers in full bloom. Afterfeeding A. conyzoides, abdomen is enlarged, and there is no defecation and rumination (Ugraunu). In folklore, leaf or seed ofradish, wild garlic, sil timur (Litsea species), timur (Zanthoxylum armatum), nirmasi (Delphinium species) and byakur (Dioscoreaspecies) are mixed and fed immediately after diagnosing.


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In Bhadaure Tamagi VDC, A. conyzoides has adverse impacts on most of the agricultural cropsas the nutrients and fertilizers supplied to the main crop are being exploited by this species.Agricultural crops particularly ginger, millet, rice and grasses were outcompeted by Ageratumand their productivity was declined (Table 13). According to local communities, there was about3 muri (273 kg) rice productions in a ropani (0.0509 ha) agricultural land at Chainpur but afterinvasion by A. conyzoides, the production was reduced to about two muri (182 kg). Reduction inproduction of cereals and grasses by A. conyzoides, Ageratina adenophora, and C. odorata inKaski district was also discussed (Bhusal 2009). According to Oerke et al. (1994), there was aloss of 13% in agricultural output due to weeds.

Ageratum is allergic and produces foul smell, which often results in giddiness, vomiting, feverand headache (Singh and Singh 2009). Wetlands, roadsides and forests and species Artemisia,Urtica, Solanum were aggressively threatened by Ageratina. Although the Ageratina havepesticidal properties (Chettri 1986) which have been applied in a few areas of Nepal, nocommercially viable applications have been found in Bhadaure Tamagi VDC.

Table 13: Impacts of A. conyzoides and A. adenophora

Figure 18: Ginger has been outcompeted by Ageratum at Chainpur and grassland has been relegatedby Ageratina at Tamagi


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3.6.8.5.2 Positive impacts

Along with negative impacts, there are several positive impacts of these two species and almosthave been capitalized by local communities of Bhadaure Tamagi VDC. The technology of usingAgeratina was already in place in VDC as a green energy resource, composting and incomegeneration offsetting the household firewood deficit, promoting soil fertility of farmland andcomplementing livelihood of rural poor. The practice of using Ageratina in particular and Ageratumconyzoidesas green manure is in increasing trend in the VDC. Increment of rice and wheat yieldwas observed on other areas of the country when green manuring of Ageratina was used(Bhattarai et al. 2006) (Table 14), because it contains 0.372% total nitrogen, 0.062%totalphosphorus, and 0.580% total kalium, as well as calcium, magnesium, iron, sulfur, silicon, zinc,boron (Sun et al. 2004). Therefore promotion of utilization of Ageratinaas green manuring isimportant in Bhadaure-Tamagi VDC.

Again, Ageratina has long been used as cattle bedding material, as found in other parts of thecountry (Shrestha 1989). The apical leaves are crushed and its paste and juice are used forbleeding control. Ageratum was also utilized for treatment of various ailments (Oladejo et al.2003), but it was not in practice in Bhadaure Tamagi. Bio-briquette made from Eupatorium wasused as green energy fuel in Bhadaure Tamagi VDC; however it was merely a demo version.Production of bio-briquette is potential in Bhadaure Tamagi VDC because it helps arrest plantinvasion, enrich the biodiversity and supply employment and additional income to locale.

Table 14: Usage of different plant species as green manuring

Table 15: Comparative use of A. conyzoides and A. adenophora


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3.6.9 Climate change and invasive species

Interacting dynamics with climate change and invasive species ranges from global patterns tolocal sites and communities of species (Burgiel and Muir 2010). Climate change may includealterations in species distributions and changes in abundance within existing distributions,resulting from direct physiological impacts on individual species, changes in abiotic factors,changes opportunities for reproduction and recruitment and alters interactions among species(Karieva et al., 1993). Invasive species may find that changes in climate produce more conduitsfor their establishment andspread (McNeely 2000). Climate change is therefore a pervasiveelement of the multiple forcing functions which maintain, generate and threaten biodiversity andinduce biological invasion.

Over a period of 30 years, maximum temperature has been increased from 19°C to 20.5°C andrainfall 5300 mm/yr to 5600 mm/yr in Bhadaure Tamagi VDC. As a coincidence, during theyears, there was an exponential increase in IAS, according to local communities. At presentthere were 54 IAS and among them 18 were highly invasive. There were no recorded archivedata about the history and number of IAS of Panchase over a period neither with local communitiesnor with government organization. However consecutive invasion of IAS Conyza, Phalaris,Borreria, Ageratina, Ageratum and Chromolaena was accounted and nine high risks possessedspecies Lantana camara, Eichhornia crissepes, Parthenium hysterophorus and above six specieswere noted. Increasing temperatures and changes in precipitation compounded by invasion ofalien species posed the additional impacts on agricultural productivity, grazing lands, and forestbiodiversity. Climate change therefore could alter almost very facets of invasion dynamics andevery interaction between different factors (Thuiller et al. 2007).

Figure 19: Uses of A. adenophora: tender shoots are as forage, green manuring and green fuel

Figure 20: Relationship of IAS introduction and increasing temperature in Bhadaure Tamagi VDC


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3.7 Management of invasive species

Effective management of IAS is clearly a priority for biological conservation worldwide. As localcommunities were aware about invasive species and their management, local initiatives asconventional measures to control them were common. Manual uprooting, burning and controllingthrough uses and weeding, hoeing and ploughing were applied as controlling measures andplantation of fodder trees and grasses was used ascontrolling and preventive measure. Multiplemethods were often applied for controlling, however almost were controlling focused. Manualuprooting, a classical tool for controlling weeds, was easy for Ageratina because it has a shallowrooting system spreading horizontally in the topsoil, but it was labor intensive to Ageratumconyzoides because A. conyzoides has profusely branched root system. Burning was the secondcommon management measure to control weeds (Table 16).

According to Rejmanek (2005), effective management of biological invasion should follow threemain steps from prevention, early detection and eradication and control backed up by integratedmanagement. Prevention is the best form of invasive species management. If prevention is nolonger possible, it is best to treat infestations when they are small to prevent them fromestablishing. Controlling the weed before seeds will reduce future problems. Control is generallybest applied to the least infested areas before dense infestations are tackled. Consistent follow-up work is required for sustainable management.The precise management measures adoptedfor any plant invasion will depend upon factors such as institutional mechanism, policy structures,terrain, the cost and availability of labor, the severity of the infestation and presence of otherinvasive species.

Nepal has various national and international legislative measures to conserve country biodiversitythrough IAS addresal. The IUCN Guidelines for Preventing Biodiversity Loss due to IAS (2000)has been designed to increase awareness and understanding of the impact of IAS. It providesguidelines for prevention of introduction, re-introduction and control as well as eradication ofIAS (IUCN 2000). Despite these arrangements, Nepal so far does not have any specific institutionsresponsible for invasive alien species research and management and it yet remains an overlookedenvironmental problem. Impact of IAS in the country has not been properly studied, albeit someadverse environmental impacts like alteration of habitat and species composition have beenexperienced through their invasion (GoN 2011b).

Table 16: Management measures to control IAS in Bhadaure Tamagi VDC (N = 28)


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CHAPTER FOUR: CONCLUSION AND WAY-FORWARD

4.1 Conclusion

Climate change impacts, such as warming temperatures, erratic rainfall, are likely to increaseopportunities for invasive species because of their adaptability to disturbance and to a broaderrange of biogeographic conditions and environmental controls. Although all ecosystems aresusceptible to invasion, the ecosystems intertwined with higher level of human interventions(e.g. forestry, agriculture, grazing lands) of Bhadaure Tamagi VDC were highly susceptible.Invasive alien species Ageratum and Ageratina were luxuriant in these habitats however theywere habitat specific.

Despite the Bhadaure Tamagi VDC is rich in plant diversity (a total of 140 plant species wererecorded during field), it is seriously plagued by invasive aliens. A total of 52 invasive alien plantspecies were recorded from the VDC, of them, 18 were highly invasive. There were 12 potentiallycompetitors invasive species and they can establish where the habitats are poorly nurtured andalready degraded.Impacts of invasive alien plant species A. conyzoides and A. adenophorawere well observed throughout the Bhadaure Tamagi VDC and none of the ecosystems wasfree from this menace. Edges of forests, agricultural lands, wetlands and roads were bereaveddue to invasion of IAS. Species such as Artemisia, Solanum xanthocarpum and Urtica speciesof fallow lands and Banso, Samo, Phurke, Mallido and Siru etc. of agricultural lands wereparticularly threatened by A. conyzoides and A. adenophorain Bhadaure Tamagi VDC.

The fallow lands and less attended agricultural plots were invaded by invasive aliens particularlyby A. conyzoides at lowlands and by A. adenophora at higher elevations along roads. Lowlandssuch as Kutmidada, Harpan, Chainpur of the VDC were more susceptible to invasion of A.conyzoides. Ageratina adenophora was homogeneous in distribution throughout the VDC exceptKutmidada and the ecosystems of Chainpur, Tamagi, Harpan were compounded. It was mostsuccessful in sites above 1400 m but in lowlands, it was co-invaded by A. conyzoides.

History of introduction of IAS in Bhadaure Tamagi dates back to 25-30 years. The first IAS werePhalaris minor (Ratnaulo) and Conyza zaponica (Salah jhar). Borreria alata (Badame jhar) wasintroduced about 20 years ago in Bhadaure Tamagi. A. adenophora was introduced andestablished before a decade in Bhadaure Tamagi and colonized almost of the habitats but inlater it was outcompeted by A. conyzoides. A. conyzoides has introduced in Bhadaure Tamagifor about 5-7 years. It has been aggressively spread as increasing the usage of nitrogen chemicalfertilizer in the VDC. Recently Chromolaena odorata (Seto banmara) has been introduced alongthe roadsides and fallow lands of the VDC. Along with these nuisance invasive species, therewere introductions and establishments of Eichhornia crissepes, Parthenium hysterophorus andLantana camara in and around Bhadaure Tamagi VDC, possessing potential risk to the localbiodiversity and socio-economy.

A. conyzoides is more harmful to the local livelihood and biodiversity than A. adenophora. Neithercattle nor goats eat Ageratum, and the areas traditionally used for grazing in upper areas of theVDC were deteriorated. Incidences of livestock mortality were common in the village becauseof accidental consumption of Ageratum and its flowers by livestock while feeding grasses. Inlast five years, there were three casualties of livestock mortality only in Harpan, Bhadaure Tamagi.Agricultural crops particularly ginger, millet, rice and grasses were outcompeted by Ageratumand their productivity was declined.

Less production is more likely lead to depopulation at rural areas. Again the migrated populationmay bring desirable crops, domestic animals, and ornamental species to other areas, potentiallyspeeding dispersal of aliens. Inadequate human resource in the VDC led the agriculture andgrasslands less nurtured and unattended, inducing rampant spread of invasive species. Current


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livelihood pattern amplified introduction of non-native species because of more interest towardsoff-farm activities, less care about seeds, fertilizers, land and soil fertility and untimely control ofweeds and invasive aliens of farmlands. As a consequence, farmers of Bhadaure Tamagi VDCare plagued by increasing number of invasive weeds and lost their properties. Despite a numberof impacts of IAS have been witnessed, detail species specific impact assessments for eachhabitat and ecosystem are yet to be carried out.

With increasing population and falling productivity of farmlands, generating alternative sourcesof income is essential. It is important to promote activities that balance the need for conservingbiodiversity and meet the requirements of local communities, on the one hand, and promotetechnologies and skills that can provide additional income through wise and cautious uses ofinvasive species on the other.Invasive alien species are a global issue that requires collaborationamong governments, economic sectors and non-governmental and international organizations.Establishment of baseline data and regular monitoring of alien species dynamics are essentialto fully understand the IAS problems and their impacts. Therefore, extensive and intensiveresearch should be promoted.Plantation of native plants species available in the country shouldbe encouraged. Until there is any firm conclusion to indicate otherwise, plantation of non-nativeand invasive species should be discouraged (Tiwari et al. 2005).

4.2 Recommendations

4.2.1 Preventive Measures

Legislation and institution development: There is a lack of specific regulations, manual,guidelines, laboratory, taxonomic capacity, etc. for the identification of IAS in Nepal (Tiwari et al.2005). The overall institutional facilities and human capacity need to be improved by providingessential technical support, strengthening coordination and sharing IAS information amongconcerned agencies and stakeholders. Legislation and regulatory procedures regardingquarantine, inspection, and cautious introduction of plants need to be strengthened, with moreattention to risk assessment before approval and follow-up monitoring after introduction (Bistaand Chaudhary 2005). Coordinated approaches at national level are important through aresponsible government institution to identify and understand the biology and ecology of IASand their monitoring and management.

Building awareness and capacity and promote community participation: It is recognizedthat public awareness plays a key role in combating invasive species as the species createecological and economic havoc including damages of human health. It is essential that awarenessneeds to create among wider stakeholders so that prevention, control, monitoring and eradicationare possible. TV, newspapers, internet and other forms of media are best to utilize to inform andeducate the general public on the impacts of invasive species. Promote community participationthrough awareness generation and involvement in efforts to address IAS through promotion ofPublic-Private Partnership (PPP) approach.

Promote scientific research: Almost of the ecosystems are invaded by IAS, threatening species,ecosystem and genetic diversity. Again the limited research and management interventionscompounded the situation. Introductions of new species are continued in the name of economicdevelopment. Therefore, scientific research is necessary to prepare basic data of species, biology,ecology, impact assessment and management guidelines.

Avoid using the known invasive species: This is the first and foremost principal of preventionis avoiding the invasive species. For this, a list of invasive species of an area should be cataloguedand widely circulated through media for awareness of general public. Identify the worst alienspecies that have invaded the natural ecosystems and assess their distribution, rates of invasion,their population dynamics and indigenous management practices, if any (Paudel and Kaini2003).


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Judicious use of inputs: Many studies have shown that high nitrogen levels and low qualityfertilizers provide an advantage to invasive species that are better adapted to using plentifulnutrients for rapid growth and establishment as compared to native species. Introduction ofEupatorium might be due to plantation materials/seedlings used in plantation of erosion ofRanibas, Paudur. Therefore, the judicious uses of the materials limit the introduction and spreadof invasive aliens.

Minimizing landscape disturbance and plantation of native species: All land uses need tobe monitored and nurtured regularly for controlling the invasion of species. Scouting at regularinterval helps in preventing spread of invasive species. Particularly, seedlings need to be checkedby uprooting. Removal of invasive species when the population is small and before floweringhelps native species to occupy the empty niche.

Plantation and afforestation of native species: A. adenophora cannot invade dense forest,shrub lands, and well-managed plantations, therefore plantation, afforestation and promotion ofnative plant species is imperative to offset the invasion. The invasive alien species are pioneerof secondary forest succession with a strong heliophilic character and vigorous vegetativedevelopment. Opened canopy due to logging or disturbance results in increased light intensities,inducing heliophilic invasive species (Joshi et al. 2011). Again closed canopy retards the growthof invasive aliens. Plantation over invaded sites is also beneficial because the soil moisture ismaintained by weed by covering the soil and it will be gradually replaced by routinely managementof planted species.

According to local communities, shade of Ficus glaberrima deters invasive aliens. Again plantationof F. glaberrima checks the open canopy, chokes the introduction of invasive aliens and providesfodder to livestock. Though it is premature to say, it seems that F. glaberrima preempts theintroduction of invasive aliens in roadsides and transition areas. However, a study aboutallelopathic effect of F. glaberrima is prerequisite before implementation.Plantation and promotionof other fodder trees, Brachiaria decumbens (Signal grass),trifolium, and legumes couldconsiderably reduce weed infestations (Wu and Xuejun 1991, Wu et al. 1996).

Collaboration: The problem of IAS is a global concern. The isolated and unilateral actions maybe insignificant to address the prevention and control IAS. Collaboration and networking amongpeer organizations, government institutions and national and international governmentorganizations is essential to design the programs, share the information, resources andtechnologies, and institutionalize the best management interventions. Trans-boundarycollaboration is also necessary to manage the species invasion.

4.2.2 Controlling Measures

Exploration and management of uses: As Eupatorium and Ageratum are useful for variouspurposes, extensive uses of these plants may control rampant spread. Species currently hasbeen used as ethnomedicinal, bedding material, green manuring, forage for goat, green fuel as

Figure 21: Ficus glaberrima (Pakhuri) controlling invasive aliens in its shade


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bio-briquette, etc. in the VDC. Extensive utilization is important as the strategy is called win-winstrategy and it is a good scope of enterprise development, employment generation at localscale and long run management of invasive species. Eupatorium contains much fibrin that canbe used to produce paper and board after deodorization treatment (Sun et al. 2004).

Uprooting: Uprooting cannot be applied independently because of the abundant seed in soiland strong asexual propagation of the plant. Again it cannot be perished effectively by onesingle way because of the topography of study area, changing climate type and big flexibility ofspecies itself. Complete uprooting including all roots and rootlets before flowering is mandatoryand controlled burning or composting or manuring or using is necessary. Once the species iseradicated and habitat is cleared, the area must be planted with fast growing grasses andfodder trees against seedling re-growth.

Integrated Crop Management (ICM): Integrated crop management involves combination ofmeasurements such as prescribed burning, regular weeding, hoeing and uprooting invasivealien species generally results in an increase in abundance and diversity of native species andcrops. Uprooting is suggested to pursue before flowering. This is the most simple and efficientmethod, but a tedious, very labor-intensive and costly (Matthew et al. 2000). However, mechanicaland manual weeding of Ageratum is limited due to its allergic effects and strong foul smell,which often results in giddiness, vomiting, fever and headache (Singh and Singh 2009). Mowingand tillage provide some measure of control, but are impractical in some situations.

Chemical control: The Alachlor at 1.5 kg/ha was found to be effective in controlling Ageratumconyzoides in maize crop (Singh and Singh 2009). Glyphosphate, dicamba and 2,4-D butylhave proven to be effective chemical treatments for Ageratina. Triclopyr may be effective forcontrolling Chromolaena odorata and Ageratina adenophora, but chemical control is impracticableand expensive and may turn counter-productive to the environment (www.hear.org./pior/species/chromolaena_odorata.htm). It is expensive due to resprouting weeds from rootstocks or rootcrowns. Chemical control is one of the effective means of control, but single applications willgenerally not provide complete control and they are expensive and contaminate environmentand fail to give season-long control. The use of chemical control must becarried out wisely toavoid the possible negative effects to the environment.

Biological control: Collection, multiplication and redistribution of gall making fruit flyProcecidochares utilis was the first used for suppression of Banmara (Ageratina adenophora)weed in 1945 in USA (Julien 1992). In 1987, fungi Mycovelosiella species and Entylomacompositarum were found to be effective than gall fly (Wan and Wang 2001). Biological controlof Ageratum conyzoides by bioagents viz. Liothrips mikaniae,Epiblema sternuana, Zygogrammabicolorata, Listronotus setosipennis, Puccinia species, etc is widely introduced. Biological controlis long term approach to controlling IAS and it is effective only to slow down the invading process(Sun et al. 2004). The combined use of natural enemies has proven to be effective as biologicalcontrol against weeds. However, these natural enemies themselves will have chances ofbecoming IAS in due course of time. Therefore biological control can be considered merely asa placebo to control invasive species.

Figure 22: A gall made by Procecodocharis utilis, gall fly in A. adenophora


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4.2.3 ActionsBased on recommendations, following actions are suggested to initiate in Bhadaure TamagiVDC at respective time interval:

Short term

• Awareness, understanding and participation of local communities on IAS need to createamong wider stakeholders so that prevention, control, monitoring and eradication of the IASare possible.

• Promote plantation of Amrisho and other fodder trees in farmlands and support in-situconservation of grasslands (kharbari). Plantation and grassland conservation is feasible inDamdame, Kutmidada, Harpan and Chainpur areas.

• Promote plantation of Ficus glaberrima (Pakhuri), a fodder tree provides fodder in leadperiods and may control alien species in transition areas, roadsides and fallow lands ofSidhane, Bhadaure, Kutmidada, Tamagi, Bhanjyang areas of the VDC.

• Support and train famers to do integrated crop management: farm with prescribed burning,hoeing, utilization of bio fertilizers, regular weeding, green manure, composting etc.

• As Eupatorium and Ageratum are useful for different purposes, scope their extensive usesand start to use it. Extensive utilization is important as it is win-win strategy and a goodscope of enterprise development, employment generation at local scale, management ofinvasive species at long run and involvement of disadvantaged, marginalized and dalit groups.

• Support local communities to do manual uprooting of Ageratum conyzoides and Ageratinaadenophorabefore flowering and equip them to use the products as energy/fuel potentialbio-briquette. Promote and develop bio-briquette/green energy development initiatives.

• Design training courses for building capacity to deal with IAS including identification,prevention, control and eradication management methods, risk assessment and explorationand uses of IAS.

• Develop guiding principles for prevention, introduction and mitigation of impacts of IAS.

Mid-term

• Promote to control use of chemical fertilizers, pesticides and hybrid species because thechemical fertilizers, pesticides and hybrid species were supposed to introduce Ageratumand Ageratina in the area and support to use bio-fertilizers, compost manure and greenmanure.

• Explore uses and applications of IAS and their products and manage to use them to controltheir spread.

• All land uses need to be monitored and nurtured regularly for controlling the invasion ofspecies.

• Identify key institution responsible for overall management of IAS and capacitate it withadequate resources, technology and information.

• Prohibition of further species introductions without prior information and evaluation isimperative, so that further deterioration of agricultural, forest and other ecosystems andenvironment is prevented.

Long-term

• Define the relationship of climate change (temp, rainfall, humidity, soil data) and invasivespecies through participatory action research for building resilience for both local communitiesand plant species.


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• Incentives on researches of biological control of Ageratina adenophora (Kalo banmara)using gall fly Procecidochares utilis.

• Strengthen coordination and information sharing mechanism among the national agenciesof forestry, agriculture, trade, environmental protection and research institutions in dealingwith forest invasive species. Promote sharing of information about invasive alien speciesthrough databases and workshops.

• Collaborate among peer organizations, government institutions and national and internationalgovernment organizations to design the programs, share the information, resources andtechnologies, and institutionalize the best management interventions.


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CHAPTER FIVE: BIBLIOGRAPHY

*h t tp : / /keys . luc idcent ra l .o rg /keys/v3/eaf r ine t /weeds/key/weeds/Media /Html /Ageratum_conyzoides (Billygoat_Weed).htm

Adebayo RA, Uyi UO. 2010. Biological control of invasive weed species: Nigerian experience.International Journal of Agricultural Research 5: 1100-1106.

Ambika SR, Jayachandra S. 1980. Influence of light on seed germination in Eupatorium odoratumL. Indian Forester 106: 637-640.

Aryal A, Dhungel SK. 2009. Species diversity and distribution of bats in Panchase region ofNepal. Tiger Paper 36(2): 14-18.

Banerji NL. 1958. Invasion of Eupatorium glandulosum (E. adenophorum) in east Nepal. Bulletinof Botanical society, University of Saugar 10 (1 and 2): 14-18.

Bani G, Gall PL. 1996. Chromolaena odorata (l.) R.M. King and H. Robinson in the Congo. In:Proceeding of distribution, ecology and management of Chromolaena odorata.ORSTOM, ICRAF and University of Guam, Mangilao, GUAM, USA, pp 25-28.

Bhattarai KR, Maren IE, Chaudhary RP. 2012. Medicinal plant knowledge of the Panchaseregion in the middle hills of the Nepalese Himalaya. Banko Janakari 21(2): 31-39.

Bhattarai S, Bhudhathoki K, Serchan DP. 2006. Organic Farming: its role in soil fertility, effect oncrop production, constraints and future strategy. In: Proceeding of national workshopon Organic Farming. DADO, Kathmandu. pp 131-137.

Bhusal YR. 2009. Local Peoples’ Perceptions on Climate Change, Its Impacts and AdaptationMeasures in Mid-Mountain Region of Nepal (A Case study from Kaski District). BSc.Forestry Research Thesis Submitted to Tribhubhan University, Institute of Forestry,Pokhara, Nepal.

Bista MS, Chaudhary MP. 2005. Forest invasive species country paper – Nepal. Proceedings ofthe Asia-Pacific Forest Invasive Species Conference, FAO.www.fao.org/docrep/008/ae944e/ae944e08.htm#bm08.1

Biswas K. 1934. Distribution of some of the common harmful exotic weeds established in thecountry. Indian Forester 60: 861-865.

Bohlmann F, Gupta RK. 1981. Six cadinene derivatives from Ageratina adenophora.Phytochemistry 20: 1432-1433.

Baruah NC, Sarma JC, Sarma S, Sharma RP. 1994. Seed germination and growth inhibitorycadinene from Eupatorium adenophorum. J. Chem. Ecol.20: 1885-1895.

Boudjelas S, Saunders A. 2002. Cooperative initiative on invasive alien species on islands.International Forestry Review 4: 282-283.

Brooks ML, D’Antonio CM, Richardson DM, Grace J, Keeley JE, DiTomasso JM, Hobbs RJ,Pellant M, Pyke D. 2004. Effects of invasive alien plants on fire regimes. BioScience54:677–688.

Brooks ML. 2003. Effects of increased soil nitrogen on the dominance of alien annual plants inthe Mojave Desert. Journal of Applied Ecology, 40: 344 – 353

Burgiel SW, Muir A. 2010. Invasive Species, Climate Change and Ecosystem-Based Adaptation:Addressing Multiple Drivers of Global Change. GISP, Washington, DC, US, and Nairobi,Kenya.

CBD (Convention on Biological Diversity). 2002. Decision VI/23: Alien species that threatenecosystems, habitats or species (Endnote I). Secretariat of the Convention on BiologicalDiversity, Montreal


42

Chaudhary SL, Mandal SN, Risal CP. 2006. Organic Fertilization: Method of Soil Managementfor Organic Farming, In: Proceeding of national workshop on Organic Farming. DADO,Kathmandu. pp 103-115.

Chettri MK. 1986. Effects of herbicides on Eupatorium adenophorum Spreng. [MSc thesis].Central Department of Botany, Tribhuvan University, Kathmandu, Nepal.

Crawley MJ. 1987. What makes a community invasible? In: Colonization, Succession and Stability(Eds) Gray AJ, Crawley MJ, Edwards PJ. The 26th Symposium of the British EcologicalSociety. Blackwell Scientific Publications, London, UK, pp 429-453.

Denslow JS. 2002. Invasive alien woody species in pacific island forests. Unaslylva 209: 62-63.

Don David. 1826. Prodromus Florae Nepalensis. M/S Bishen Singh Mahendra Pal Singh, 23-A,New Connaught Place, Dehradun and M/S periodical experts D-42, Vivek vihar, Delhi,India.

Dukes JS, Mooney HA. 2004. Disruption of ecosystem processes in western North America byinvasive species. Rev Chil Hist Nat 77: 411–437.

Dulloo ME, Kell SP, Jones CG. 2002. Conservation of endemic forest species and the threat ofinvasive species. Impact and control of invasive alien species on small islands.International Forestry Review 4: 277-285.

Engel K, Tollrian R, Jeschke JM. 2011. Integrating biological invasion, climate change andphenotypic plasticity. Communicative & Integrative Biology 4:3, 247-250; May/June,Landes Bioscience.

Gautier L. 1992. Taxonomy and distribution of a tropical weed: Chromolaena odorata (L.) R.King & H. Robinson. Candollea 47: 645-662.

Geldenhuys CJ. 1986. Costs and benefits of Australian Blackwood Acacia melanoxylon in SouthAfrican forestry. In: Macdonald IAW, FJ Kruger, AA Ferrar (eds). The ecology andmanagement of biological invasions in Southern Africa. Cape Town: Oxford UniversityPress, pp275-284.

GoN. 2011a. Study on Invasive Alien Species (IAS) as Drivers to Deforestation and Degradationof Forests in Different Physiographic Regions of Nepal. Climate Change REDD Cell,Ministry of Forests and Soil Conservation, Kathmandu, Nepal.

GoN. 2011b. Wetland invasive alien species (IAS) management guidelines. Conservation andSustainable Use of Wetlands of Nepal (CSUWN) and Ministry of Forests and SoilConservation, Kathmandu, Nepal.

GoN. 2012a. Protected forest of Nepal. Department of Forest, Ministry of Forests and SoilConservatuion. Kathmandu, Nepal, www.dof.gov.np

GoN. 2012b. National population and housing census 2011. Government of Nepal, CentralBureau of Statistics. Kathmandu, Nepal.

Grabherr G, Gottfried M, Pauli H. 1994. Climate effects on mountain plants. Nature 369: 448–450.

Grime JP. 1998. Benefits of plant diversity to ecosystems: immediate, filter and founder effects.Journal of Ecology 86: 902–910.

He DY, Liu LH, Jing GF, Wei Y. 1988. Research Progress of Biological Control of Eupatoriumadenophorum, Progress in Ecology 5(3): 163-168.

Hobbs RJ, Arico A, Aronson J, Baron JS, Bridgewater P, Cramer VK, Epstein PR, Ewel JJ, KlinkCA, Lugo AE,Norton D, Ojima D, Richardson DM, Sanderson EW,Valladares F, Vilà M,Zamora R, Zobel M. 2006. Emerging ecosystems: theoretical and management aspectsof the new ecological world order. Global Ecology and Biogeography 15: 1–7.


43

Hoevers R, Mboob SS. 1996. The status of Chromolaena odorata (L.) R. M. King and H. Robinsonin West and Central Africa. In: Proceeding of distribution, ecology and management ofChromolaena odorata. ORSTOM, ICRAF and University of Guam, Mangilao, GUAM,USA, pp 1-5.

Husain T, Agnihotri P. 2009. Invasive alien species and climate change. National conference oninvasive alien species. Lucknow, India, pp 36-38.

IPCC. 2007. Climate Change 2007: Impacts, Adaptation, and Vulnerability. Working Group IIContribution to the Intergovernmental Panel on Climate Change Fourth AssessmentReport. Summary for Policy Makers. IPCC, Geneva, Switzerland. Available at: /http://www.ipcc.ch/SPM13apr07.pdf.

IUCN. 2000. IUCN Guidelines for the Prevention of Biodiversity Loss due to Biological Invasion.Gland, Switzerland.

IUCN. 2001. Alien invasive species. Report of workshop on alien invasive species. GlobalBiodiversity Forum South and Southeast Asia Section, IUCN Regional BiodiversityProgramme, Asia, Sri Lanka.

Jianghua S. 2005. Forest Invasive Species: Country Report – P. R. China. Proceedings of theAsia-Pacific Forest Invasive Species Conference, FAO.www.fao.org/docrep/008/ae944e/ae944e08.htm#bm08.1

Joseph J, Kharkongor P. 1981. A preliminary ethnobotanical survey in the Khari and Jaintic hills.Meghalaya. In: Jain SK (ed). Glimpse of Indian ethnobotany New Delhi. Oxford andIBH Publishing Co. pp 115-123.

Joshi C, Andel JV, Skidmore A, Leeuw JD, Duren IV. 2011. Morphological plasticity of corms inenhancing invasion of Chromolaena odorata. Banko Janakari 21(2): 3-12.

Joshi SL. 1991. Biological control inception in Nepal, SAARC symposium workshop on thebiological control of agriculturally important plant pests. Centre for applied molecularbiology, Canal Bank Road, Lahore, Pakistan, pp 72-77.

Julian MH. 1992. Biological Control of Weeds. A World Catalogue of Agents and their TargetWeeds (3rd edition). CAB International. Wallingford, UK.

Kennedy TA, Shahid N, Katherine MH, Jokannes MHK, David T, Peter R. 2002. Biodiversity asa barrier to ecological invasion. Nature 417: 636-638.

Kluge RL. 1989. Insect against triffid weed in Natal. Weed Abstr. 39, No. 1532.

Koirala R. 1998. Botanical diversity within the project area of Machhapuchhre DevelopmentOrganization. Bhadaure-Tamagi, Kaski. Kathmandu, Nepal.

Kunwar RM and Uprety Y. 2005. Alien invasive plant (Eupatorium species-Banmara andBanmasa) in Nepal. Alien Newsletter21: 5-7. University of Auckland, New Zealandwww.issg.org/aliens

Kunwar RM. 2003. Invasive alien plants and Eupatorium: biodiversity and livelihood. HimalayanJournal of Sciences1(2): 129-133.

Lodge DM, Williams S, MacIsaac HJ, Hayes KR, Leung B, Reichard S, Mack RN, Moyle PB,Smith M, Andow DA, Carlton JT, McMichael A. 2006. Biological invasions:Recommendations for U.S. policy and management. Ecological Applications 16(6): 2035-2054.

Lowe S, Browne M, Boudjelas S, Poorter DM. 2000. 100 of the Worlds Worst Invasive AlienSpecies. A selection from the Global Invasive Species Database. (www.issg.org).

Lucas EO. 1989. Siam weed (Chromolaena odorata) and crop production in Nigeria. OutlookAgriculture 18: 133-142.


44

Mcneely JA. 2000. Global strategy for addressing the problem of IAS. Global Invasive SpeciesProgramme, Switzerland.

Maren I, Bhattarai KR, Chaudhary RP. 2013. Forest ecosystem services and biodiversity: theresource flux from forests to farms in the Himalayas. Draft report. Kathmandu, Nepal

Matthew JWC, Carol AE, Harry CE, Peter ACO. 2000. Can failure be turned into success forbiological control of Mile-a-Minute Weed (Mikania micrantha)? Proceedings of the XInternational Symposium on Biological Control of Weeds. 4-14 July 1999, MontanaState University, Bozeman, Montana, USA. Neal R. Spencer (ed.) pp 155-167.

Moody JO, Adebiyi OA, Adeniyi BA. 2004. Do Aloe vera and Ageratum conyzoides enhance theanti-microbial activity of traditional medicinal soft soaps (Osedudu). Journal ofEthnopharmacology 92: 57-60.

Mooney H, Larigauderie A, Cesario M, Elmquist T, Hoegh-Guldberg O, Lavorel S, Mace GM,Palmer M, Scholes R, Yahara T. 2009. Biodiversity, climate change, and ecosystemservices. Current Opinion in Environmental Sustainability 1(1): 46-54.

Heller NE, Zavaleta ES. 2009. Biodiversity management in the face of climate change: A reviewof 22 years of recommendations. Biological Conservation 142:14-32.

Muniappan R, Nandwani D. 2002. Survey of Anthropod Pests and Invasive Weeds in the Republicof Marshall Islands. Publication no.1, College of the Marshall Islands.

NBS. 2002. Nepal Biodiversity Strategy. Government of Nepal Ministry of Forests and SoilConservation, Kathmandu, Nepal.

NEPA. 1998. Biodiversity country report Bejing: National Environment Protection Agency Officeof Technology Assessment 1993 Harmful non-indigenous species in the United States.OTA -F-565.

Ohlemuller R, Walker S, Wilson JB. 2006. Local vs regional factors as determinants of theinvisibility of indigenous forest fragments by alien plant species. Oikos 112: 493-501.

Oladejo, OW, Imosemi IO, Osuagwu FC, Oyedele OO, Oluwadara OO, Ekpo OE, Aiku A,Adewoyin O, Akang EEU. 2003. A comparative study of the wound healing properties ofhoney and Ageratum conyzoides. African Journal of Medical Sciences32: 193-196.

Ooi PAC, Sim CH, Tay EB. 1988. Status of the arctiid moth introduced to control Siam weed inSabah. Planter (Malaysia) 64: 298-304.

Pandey RR, RB Paneru. 2006. Pest Management in Organic Farming through Conservation ofNatural Enemies. In: Proceeding of national workshop on Organic Farming. DADO,Kathmandu. pp 138-143.

Pant HM, Sharma N. 2011. Invasive alien species: a global scenario.Research Journal ofAgricultural Sciences 2(1): 180-184.

Parmesan C, Yohe G. 2003. A globally coherent fingerprint of climate change impacts acrossnatural systems. Nature 421: 37–42.

Paudel KC, Kaini BR. 2003. Nepal, sharing experiences from agricultural and forestry sectors,In: Pallewatta N, JK Reaser, AT Gutierrez. (eds.). Invasive alien species in South-Southeast Asia: National Reports & Directory of Resources. Global Invasive SpeciesProgramme, Cape Town, South Africa.

Pickart AJ, Miller LM, Duebendorfer TE.1998. Yellow bush lupine invasion in northern Californiacoastal dunes I. Ecological impacts and manual restoration techniques. RestorationEcology6: 59–68.

Pimentel D, Zuniga R, Morrison D. 2005. Update on the environmental and economic costsassociated with alien-invasive species in the United States. Ecological Economics 52:273–288.


45

Poudel BS, Thapa HB. 2012. An assessment of existing studies on invasive alien plant speciesof Nepal. BankoJanakari 22 (1): 28-36.

Pysek P, Prach K. 1994. How important are rivers for supporting plant invasions? In: de Waal L,Child LE, Wade PM, Brock JH (eds.) Ecology and management of invasive riversideplants. John Wiley & Sons, New York, USA, pp 23-31.

Randall J, Marinelli J. 1996. Invasive Plants: Weeds of the global garden. Brooklyn BotanicGarden Club, Inc. Handbook No. 149: 111.

Reiter P. 2001. Climate change and mosquito-borne disease. Environmental Health Perspectives109(Supplement 1):141-161.

Rejmanek M, Richardson DM, Higgins SI, Pitcairn M. 2000. Ecology of invasive plants: State ofthe Art. In McNeely.

Rejmanek M, Richardson DM, Higgins SI, Pitcairn MJ, Grotkopp E. 2005. Ecology of invasiveplants: state of the art. In: Mooney HA, Mack RN, McNeely JA, Neville L, Schei PJ,WaageJ (eds) Invasive alien species: a new synthesis, Island Press, Washington DC, pp 104–161.

Rejmanek M, Richardson DM. 1996. What attributes make some plant species more invasive?Ecology 77: 1655–1661.

Rejmanek M. 1999. Invasive plant species and invasible ecosystems. In: Sandlund OT, ScheiPJ,Vilken A (eds), Invasive species and biodiversity management. Luwer Dordrecht 79-102.

Rejmanek M. 2005. Invasive plants: Approaches and predictions. Austral Ecol.25: 497–506.

Ricciardi A, Steiner WWM, Mack RN, Simerioff D. 2000. Towards a global information systemfor invasive species. Bioscience 50(3): 239-244.

Richardson DM, Higgins SI. 1998. Pines as invasion in the Southern hemisphere. In RichardsonDM (ed). Ecology and biogeography of Pinus. Cambridge: Cambridge University Press,pp 450-473.

Rouw AD. 1996. Chromolaena odorata in the farming systems of South-West Côte d’Ivoire. In:Proceeding of distribution, ecology and management of Chromolaena odorata.ORSTOM, ICRAF and University of Guam, Mangilao, GUAM, USA, pp 76-87.

Sale OE, Chapin FS, Gardner RH, Lauenroth WK, Mooney HA, Ramakrishnan PS. 1999. Globalchange, biodiversity and ecological complexity. In: The Terrestrial Biosphere and GlobalChange: Implications for Natural and Managed Ecosystems (Eds Walker B, Steffen W,Canadell J, Ingram J). Cambridge University Press, Cambridge, UK, pp 304-328.

Sankaran KV, Murphy ST, Sreenivasan SA. 2005. When good trees turn bad: the unintendedspread of introduced plantation tree species in India.

Shrestha TB. 1989. Development of the Arun river basin. Nepal: Country report on biologicaldiversity Kathmandu, pp133.

Singh RP, Singh RK. 2009. Invasive alien weeds, a threat to agriculture and biodiversity. Nationalconference on invasive alien species. Lucknow, India, pp 118-121.

Somvanshi P, Khan MS, Raj SK, Seth PK. 2009. Ageratum conyzoides and Partheniumhysterophorus: alternate host of Begomovirus and Phytoplasma. National conferenceon invasive alien species. Lucknow, India, pp 44-45.

Stern N. 2006. The Economics of Climate Change. HM Treasury, London, UK.

Subedi A, Chaudhary, RP, Vermeulen JJ, Gravendeel B. 2011. A new species of Panisea(Orchidaceae) from central Nepal. Nordic Journal of Botany 29: 361-365.


46

Subedi A, Subedi N, Chaudhary RP. 2007. Panchase forest: An extraordinary place for wildorchids in Nepal. Pleione 1: 23-31.

Sun XY, Lu ZH, Sang WG. 2004. Review on studies of Eupatorium adenophorum-an importantinvasive species in China. Journal of Forestry Research, 15(4): 319-322.

Thapa GB. 1996. Land use, land management and environment in a subsistence mountaineconomy in Nepal. Agriculture, Ecology and Environment 57: 57-71.

Thomas DF. 2003. Invasive species of forest in the United States—2003, The Unwelcome Guests.In Proceedings of the Asia-Pacific Forest Invasive Species Conference, Kunming, China,17–23 August 2003, McKenzie P, Brown C, Jianghua S, Jian W, (eds); FAO: Rome,Italy; pp 121–129.

Thuiller W, Richardson DM, Midgley GF. 2007. Will climate change promote alien plant invasion?Ecological Studies 193: 197-211.

Thuiller W, Richardson DM, Rouget M, Proches S, Wilson JRU. 2006. Interactions betweenenvironment, species traits and human uses describe patterns of plant invasions. Ecology87: 1755–1769.

Tjitrosemito S. 1996. The management of Chromolaena odorata (L.) R. M. King and H. Robinsonin Indonesia. In: Proceeding of distribution, ecology and management of Chromolaenaodorata. ORSTOM, ICRAF and University of Guam, Mangilao, GUAM, USA, pp 135-142.

UNDP/MDO. 2006. Panchase Biodiversity Management Project. UNDP/GEF/SGP andMachhapuchre Development Organization, Pokhara, Nepal.

Upadhyay M. 2012. Panchase protected Forest: an introduction. Ministry of Forests and SoilConservation, Kathmandu, Nepal.

Walther GR, Post E, Convey P, Menzel A, Parmesan C, Beebee TJC, Fromentin JM, Hoegh-Gudberg O, Bairlein F. 2002. Ecological responses to recent climate change. Nature416:389–395.

Walther GR, Roques A, Hulme PE, Sykes MT, Pysûk P, Kühn I, Zobel M, Bacher S, Botta-DukátZ, Bugmann H, Czúcz B, Dauber J, Hickler T, Jarovík J, Kenis M, Klotz S, Minchin D,Moora M, Nentwig W, Ott J, Panov VE, Reineking B, Robinet C., Semenchenko V,Solarz W, Thuiller W, Vilà M, Vohland K, Settele J. 2009. Alien species in a warmerworld: Risks and opportunities. Trends in Ecology and Evolution 24(12): 686-693.

Wan FH, Wang R. 2001. Biological weed control in China: an updated report in alien invasivespecies. IUCN Regional Biodiversity Programme, Asia.

Westbrooks, R. 1991. Plant Protection Issues-I. A commentary on new weeds in the UnitedStates. Weed Technology 5: 232-237.

Witkowski ETF, Wilson M. 2001. Changes in density, biomass, seed production and soil seedbanks of the non-native invasive plant, Chromolaena odorata, along a 15 yearchronosequence. Planta Ecology 152: 13-27.

Wittenberg R, Cock MJW (Eds.) 2001. Invasive Alien Species: A Toolkit of Best Prevention andManagement Practices. CAB International and GISP, Oxon, UK.

Wu R, Bizhi H, Zhengyun G. 1996. The Use of Signal grass (Brachiaria decumbens Stapf.) andlegumes to control Chromolaena odorata. In: Proceeding of distribution, ecology andmanagement of Chromolaena odorata. ORSTOM, ICRAF and University of Guam,Mangilao, GUAM, USA, pp 143-147.

Wu R, Xuejun X. 1991. Cultural control of Chromolaena odorata planting Signalgrass (Brachiariadecumbens Stapf) in Southern Yunnan, People’s Republic of China. Ecology andManagement of Chromolaena odorata, BIOTROP 44: 83-89.


47

Yehouenou A. 1996. A survey of Chromolaena odorata in Benin. In: Proceeding of distribution,ecology and management of Chromolaena odorata. ORSTOM, ICRAF and Universityof Guam, Mangilao, GUAM, USA, pp 19-24.

Yelenik SG, Stock WD, Richardson DM. 2007. Functional group identity does not predict invaderimpacts: Differential effects of nitrogen-fixing exotic plants on ecosystem function.Biological Invasions 9: 117-125.

Zavaleta ES, Hulvey KB. 2004. Realistic species loss disproportionately reduces grasslandresistance to biological invaders. Science 306:1175–1177.


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ANNEX

Annex 1. List of respondents for study of IAS in BhadaureTamagi VDC, Panchase


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Annex 2. Questionnaire used for survey

Impact Assessment of Invasive Ecosystem in Selected Ecosystems of Bhadaure-Tamagi VDC of Panchase Area, Nepal

Date:District: VDC: Ward: Village:Name of the interviewer: Name of the respondent:

1. Are you familiar with invasive species?Well known ......... general ........... little ...........

2. Have you observed any invasive species in your area?Yes……………….. No…………

3. If yes, please mention the name of these invasive species

4. Since when you had observed the first invasive species in your area?a. Less than 5 years b. 6-10 years c. 11 above

5. May we have more information of IAS in your area (species specific)?

6. Indicate your idea about the IAS (Tick one).

7. If yes, what are the problems/benefits?

8. Which are the factors affecting your livelihood and biodiversity? (Tick appropriate)

9. What are the factors responsible for introduction and spread of Invasive Species?


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10. Please give us some plants/wildlife that are particularly threatened by invasive alienplants and precisely by Ageratum and Eupatorium?

11. If Ageratum is harmful, to what extent the ecosystems are affected?

12. If Eupatorium is harmful, to what extent the ecosystems are affected?

13. Where are they abundantly seen?

14. From your experience, where is the potential cover of these species in your VDC?

15. What are the other natures of these two species? (give data/Information)


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16. Their infestation/spreading rate in your VDC?

17. How was the fast spread of these species possible?

18. Three major problems/impacts you have faced/seen/heard due to these two species?

19. Other associated/hidden impacts of these two species?

20. What are the likely threats/challenges of these two invasive species?

· ·

21. What are the preventive/controlling measures have you followed?

· ·

22. The best three strategies we should run to manage IAS?


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23. Are there community/eco-friendly best options or biological control of these species?

24. Have you seen any possibilities or options to utilise these invasive species such as Bio Briquette, fertiliser, etc. Yes……………….. No…………

25. If yes, what are they?


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Annex 3. Per Month Maximum Temperature Record


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Annex 4. Per month minimum temperature record


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Annex 5: Total Species and their Frequency in Different Habitats


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Annex 6. List of invasive plant species in Bhadaure Tamagi,Panchase and Nepal


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Annex 7: Definitions of key terms

Alien species (synonyms: non-native, non-indigenous, foreign, exotic): a species, subspecies,or lower taxon introduced outside its normal past or present distribution; includes any part,gametes, seeds, eggs, or propagules of such species that might survive and subsequentlyreproduce.

Casual alien species: Alien species that may flourish and even reproduce occasionally in anarea, but which do not form self-replacing populations, and which rely on repeated introductionsfor their persistence (Richardson et al. 2000).

Eradication: The extirpation of the entire population of an alien species in a managed area;eliminating the IAS completely.

Establishment: The process of a species in a new habitat successfully reproducing at a levelsufficient to ensure continued survival without infusion of new genetic material from outside thesystem.

Intentional introduction: The purposeful movement by humans of a species outside its naturalrange and dispersal potential (such introductions may be authorised or unauthorised) (IUCN,2000) (c.f. unintentional introduction).

Introduction: The movement, by human agency, of a species, subspecies, or lower taxon(including any part, gametes, seeds, eggs, or propagule that might survive and subsequentlyreproduce) outside its natural range (past or present). This movement can be either within acountry or between countries (IUCN, 2000).

Invasive alien species: An alien species whose establishment and spread threaten ecosystems,habitats or species with economic or environmental harm. These are addressed under Article8(h) of the CBD.

Native species (synonym: indigenous species): a species, subspecies, or lower taxon livingwithin its natural range (past or present), including the area which it can reach and occupy usingits own legs, wings, wind/water-borne or other dispersal systems, even if it is seldom foundthere.

Naturalized species: alien species that reproduce consistently (cf. casual alien species) andsustain populations over more than one life cycle without direct intervention by humans (or inspite of human intervention); they often reproduce freely, and do not necessarily invade natural,seminatural or human-made ecosystems.

Pest: “Any species, strain or biotype of plant, animal or pathogenic agent injurious to plants orplant products” (IPPC).

Suppression: reducing population levels of the IAS to an acceptable threshold.

Unintentional introduction: a species utilizing unwitting humans or human delivery systemsas vectors to disperse and become established outside its natural range (IUCN, 2000).

Weeds (synonyms: plant pests, harmful species; problem plants): Plants (not necessarily alien)that grow in sites where they are not wanted and have detectable negative economic orenvironmental effects; alien weeds are invasive alien species.

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