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Fantahun Ali Amedie Master thesis in Atmospheric Science with orientation towards Environmental Science (60 HEC) Department of Biological and Environmental Sciences University of Gothenburg Impacts of Climate Change on Plant Growth, Ecosystem Services, Biodiversity, and Potential Adaptation Measure

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Fantahun Ali Amedie

Master thesis in Atmospheric Sciencewith orientation towards Environmental Science (60 HEC)

Department of Biological and Environmental SciencesUniversity of Gothenburg

Impacts of Climate Change on Plant Growth, Ecosystem Services, Biodiversity, and Potential Adaptation Measure

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Impacts of Climate Change on Plant Growth, Ecosystem Services, Biodiversity and Potential Adaptation Measures

Master thesis in Atmospheric Science with Orientation towards Environmental Science (60 HEC)

Fantahun Ali Amedie

Supervisor: Dr Göran Wallin, University of Gothenburg,

Department of Biological and Environmental Science (Inst. för biologi och miljövetenskaper)

Box 461, SE- 405 30 Göteborg

Sweden

2013

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Table of Content

1. INTRODUCTION .............................................................................................................................................. 8

2. GENERAL OVERVIEW OF CLIMATE CHANGE ......................................... FEL! BOKMÄRKET ÄR INTE DEFINIERAT.

2.1 CAUSES FOR CLIMATE CHANGE .............................................................................................................................. 11 2.2 EFFECTS OF CLIMATE CHANGE ON ECOSYSTEMS AND ECOSYSTEM SERVICES ..................................................................... 14

2.2.1 Precipitation Change ............................................................................................................................. 16 2.2.2 Rise in Temperature ............................................................................................................................... 16

3. PLANT RESPONSES TO CLIMATE CHANGE ..................................................................................................... 17

3.1 RESPONSES OF FIELD CROPS TO CLIMATE CHANGE. ..................................................................................................... 18 3.2 RESPONSES OF FOREST TREES TO CLIMATE CHANGE. ................................................................................................... 19 3.3 PHOTOSYNTHESIS AND PLANT RESPIRATION PROCESSES. ............................................................................................. 19 3.4 AGRICULTURE AND CLIMATE CHANGE ..................................................................................................................... 24

3.4.1 Climate variables and productivity ........................................................................................................ 24 3.4.2 Direct effects of climate change on food crops ..................................................................................... 25 3.4.3 Indirect effect of temperature ............................................................................................................... 25 3.4.4 Impacts of temperature × [CO2] interaction on plant processes ........................................................... 26

4. ADAPTATION MEASURES FOR CLIMATE CHANGE ......................................................................................... 27

4.1 GENERAL OVERVIEW ........................................................................................................................................... 27 4.1.1 Definition ............................................................................................................................................... 27 4.1.2 Importance of adaptation ..................................................................................................................... 28 4.1.3 Dimension of adaptation ....................................................................................................................... 30 4.1.4 Steps in adaptation ................................................................................................................................ 30 4.1.5 Evaluation of adaptation ....................................................................................................................... 32

4.2 ADAPTATION OPTIONS ......................................................................................................................................... 32 4.3 PRIVATE ADAPTATIONS ........................................................................................................................................ 33 4.5 ADAPTATION STRATEGIES FOR AGRICULTURE ............................................................................................................ 35 4. 6 TOOLS IN PLANNING ADAPTATION ......................................................................................................................... 38 4.7 ADAPTATION IN TERMS OF SOME AGRO ECOLOGICAL ASPECTS ...................................................................................... 38 4.8 SUSTAINABLE ADAPTATION MEASURES .................................................................................................................... 38 4.9 PARTNERSHIPS IN PRACTICING ADAPTATION AND MITIGATION FOR POOR RURAL PEOPLE ................................................... 41

5. PRACTICING ADAPTATION, KEY POINTS AND QUESTIONS TO BE ANSWERED .............................................. 42

5.1. HOW CAN PREFERABLE TECHNICAL SOLUTIONS FOR CLIMATE CHANGE BEING APPLICABLE BY SOCIETIES? .............................. 42 5.2 WHAT WILL HAPPEN TO POOR COMMUNITY IN HIGH VULNERABLE DEVELOPING COUNTRIES BECAUSE OF LESS ADAPTATION

OPTIONS? ............................................................................................................................................................... 43 5.3 CRITERIA FOR GOOD ADAPTATION PRACTICE ............................................................................................................. 45 5.4 WHAT KINDS OF ADAPTATION MEASURES FOR CLIMATE CHANGE ARE SUCCESSFUL IN FORESTRY? ........................................ 46

5.5.1 Locally practiced traditional adaptation actions in forestry .................................................................. 47 5.5.2 Common barriers in adaptation ............................................................................................................ 48

6. TECHNIQUES OF MITIGATION IN AGRICULTURE AND FORESTRY .................................................................. 49

7. DISCUSSION .................................................................................................................................................. 50

8. CONCLUSION ................................................................................................................................................ 53

9. REFERENCES ................................................................................................................................................. 55

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List of table page Table 1: Major greenhouse gasses, current level, global warming potential and their life time in the atmosphere…………………………………………………………………………………12 Table 2: Adaptation options implemented by private and public sectors………………………....33 Table 3: Example of simple adaptation options in agriculture, which are easily applicable..36 Table 4: different tools, which can be used for planning and practicing adaptation options to climate change………………………………………………………………………………………………..…39 Table 5: Examples of potential adaptation measures which can be implemented in relation to poverty reduction…………………………………………………………………………………………..40 List of figures page Figure 1: The general feature of climate change, its impact on human and earth systems…………………………………………………………………………………………………….……………………......10 Figure 2: Global average, annual anthropogenic greenhouse gases level and main sources ………………………………………………………………………………………………........................13 Figure 3: Main sectors which take part in anthropogenic greenhouse gas emission...........................................................................................………………….………………….14 Figure 4: Most important biogeochemical processes in plant and forest ecosystems..................................................................................…………………………..……………..16 Figure 5a: Change in the rate of crop development as a function of temperature….…………...20 Figure 5b: Change in the rate of photosynthesis and respiration as a function of temperature...………………………………………………………………………………………………………………………20 Figure 6: Direct and indirect effects of rise in temperature on different component, processes in plant and in the soil………………………………………….……………………………………………...23 Figure 7: Steps in planned adaptation to climate change …………………………………………………....32 Figure 8: Farmers opportunity in crop choice adaptation under change in To……………………...34 Figure 9a: Drought effect on poor society …………………………………………………………………………...44 Figure 9b: Resilience of farmers by using option of adaptation…………………………………………….44 Figure 9c: Adapting the drought after using adaptation options through time…….…………......45

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Abbreviations

(A) – Assimilation rate CAM – Crassulacean acid metabolism CCA – Climate Change Adaptation [CO2] – Carbon dioxide concentration DRR – Disaster Risk Reduction FACE – Free-air CO2 Enrichment FAO – Food and Agricultural Organization GEF – Global Environmental Facility GHG – Greenhouse Gas (Gs) – Stomatal conductance GWP – Global Warming Potential IFAD – International Fund for Agricultural Development IPCC – Inter Governmental Panel on Climate Change LDCF – Least Developed Country Fund NPP – Net Primary Production ppb – Parts Per billion ppm – Parts Per million ppt – Parts Per trillion Q 10 – Proportional change in respiration with a 10oC increase in temperature R – Respiration REDD – Reduced Emissions from Deforestation and Forest Degradation Rubisco – Ribulose-1, 5-bisphosphate carboxylase/ oxygenase SCCF – Special Climate Change Fund SPA – Strategic Priority on Adaptation UNFCCC – United Nations Frame work Convention on Climate Change VPD – Vapor Pressure Deficit VOC – Volatile Organic Compound WFP – World Food Program

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Acknowledgment

I sincerely thank the University of Gothenburg for this study program. At the outset, my deepest heartfelt thanks go to my supervisor Dr Göran Wallin, Department of biological and environmental sciences at the University of Gothenburg for all his motivation, sharing knowledge, providing me different reference materials, and guide me during my work; I would like to say thanks also to Professor Håkan Pleijel for his support.

Special thanks to Olof Persson, Bruktawit, Jamal Mohammed and all friends for their follow up and always help full throughout my study.

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Abstract

Assessing the impacts of climate change will be a vital task in developed as well as in developing countries because of many interdependent physical, biological and chemical processes are ongoing in earth and human systems. These processes can be affected by change in climate, causing an effect on natural resources (water resources, forest products, etc.), on biodiversity, ecosystem services and on plants in general, some positive and on others negative effects, such as, altering biophysical relationship, shrinking of habitats, desertification and general shift in natural world.

Warming directly affects rate of plant respiration, photosynthesis, and other biogeochemical processes. For instance, enhanced CO2 concentration can increase photosynthetic rate especially for plants growing under warm and dry condition such as C3 plants. Naturally, plants have their own mechanism to tolerate a certain level of increased temperature. As soil temperature increase, the decomposition rate of organic matter will increase, and then nutrient mineralization and availability for plants uptake become increased at presence of sufficient water if other conditions are unchanged. Thus, the interaction and different combination effect of rise CO2 concentration and temperature is determined by soil properties, water, mineral and nutrient availability etc, as a result the expected response of plants in different environments and climate variability can be either positively or negatively affected.

Therefore, in summary two basic measures are necessary to reduce impacts of climate change; 1) practicing mitigation (reducing causes of climate change) by reducing emission of greenhouse gases (GHGs) from the source, by substitution and conservation of energy, improving carbon sequestration, etc and 2) practicing potential adaptation measures, (e.g. reducing the impacts of climate change). Important examples of adaptations are; a) reducing vulnerability (degree of susceptibility of a system to a certain damage) to climate change impacts, focusing on coping strategies and practices to become beneficial by using opportunities associated to climate change by reducing susceptibility and external forces to develop the ability of resilience (increasing tackling capacity of the community and sectors to reduce risk and damages); b) have effective conservation strategies to maintain natural distribution of biodiversity and ecosystem services, and conserve species and genetic diversity; c) Improving productivity in terms of quality and quantity is vital to satisfy human needs, through adjusting different growth factors and solving effects of extreme events and associated problems, e.g. preventing spread of pathogens, weeds, dispersion of insect and pests etc; d) minimize impacts of climate change (its cause and effects) moving forward in researching to identify the responses of plant species to different variable climate conditions, and identifying uncertainty in climate and try to avoid challenges in practicing adaptation; e) finally, increased environmental benefits from forest ecosystems by afforestation and reforestation to reduce degradation and loss of habitats.

Key words: Climate changes, ecosystem services, plant growth, productivity, land use change, biodiversity, adaptation, species, mitigate and vulnerability.

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1. Introduction Current and predicted pattern of global climate change are a major concern in many areas of socio- economic activities, such as agriculture, forestry, etc., and is a major threat for biodiversity and ecosystem function (Lepetz et al., 2009). Climate change is a result from emission of greenhouse gases (e.g. CO2, CH4, & N2O, etc.) in the past century that will cause atmospheric warming (IPCC, 2007). The effects have become particularly obvious over the last 30 years in the natural environment and it will affect all level of life, from the individual, population species community and ecosystem to the eco-region level (Lepetz et al., 2009).

The main issue that every country, private sector, institutions, etc. must face is how to adapt the future changes in climate that will occur. Agriculture is one of the sectors, which are both sensitive to global warming (e.g. through, atmospheric temperature, precipitation, soil moisture, sea level and humidity) and contributes to climate change. In response to changes in climate, through practicing adaptation options it is important to protect both market and non-market benefits from damages. Examples of such adaptive responses is improved water management (irrigation), improved crop varieties and other adjustments in agricultural practices that could counter act the effects of climate change (Auger & Suwanraks, 1999).

A report from Intergovernmental panel on climate change (IPCC, 2007) shows that CO2 released from agriculture to large extent comes from microbial decay or burning of plant residue and organic matter. CH4 produced during fermentation of organic material, emitted from ruminant animals, stored manure (waste), and rice farming under flooded condition, etc. N2O generated by microbial transformation of nitrogen in soil, manures and often, enhanced where there is high availability of N, especially under wet condition (Smith et al., 2007). The production of greenhouse gases from agriculture is complex and heterogeneous, but active management of agricultural system can give possibilities for mitigation (IPCC, 2007).

The ecosystem, and balance between different dominating species and abiotic factors can be highly affected by climate change. Tree cover provides a habitat for numerous herbaceous plants, fungi, and lichens, small and large animals. Thus, loss of tree cover will affect virtually all species that make up a complex forest ecosystem (Hardy, 2003). In order to increase the function of component of some terrestrial species we need to conserve and manage agro-ecosystems.

Forests provide many services to human being and natural systems such as provision of food, medicine, regulation of hydrologic cycle, recreational use and aesthetic value etc. In addition, forest regulates the atmospheric exchange of light energy, carbon dioxide and water (Bonan, 2008). Even though plants have their own natural mechanisms to tolerate some level of adverse conditions, physiological responses of forest (plants) under climate change condition are highly determined by the limiting factors of a particular site of forest growth. For example, increasing

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temperature may also increase vapor pressure deficit (VPD) of the air, and thereby increase transpiration rates that may result in adverse effects, especially on dryer sites (Boyd, 2010).

Following growth of human population and industrialization, there is a resource competition among humans over land use change, deforestation or over-harvesting, expansion of farmland and pastureland, which causes a negative impact on biodiversity of different habitats, forest cover, forest growth, and ecosystem services. Following these pressures, the continuous rise in temperature, enhancement of concentration of CO2, sea level rise, and stress of nutrient and water availability can have additional negative effects as well as positive impacts on different processes in earth and human systems. For these and many other reasons, we need to protect our benefits through practicing adaptation measures.

The response of humans to climate change includes two basic measures, adaptation and mitigation addressing the impacts and causes of climate change respectively. As defined by IPCC (2007), adaptation includes a set of actions by individuals, society, or groups and governments, i.e. continuous stream of activities, attitudes that informs decisions about all aspects of life. Adaptation reflects existing social norms and processes, which can be motivate by many factors to moderate harm or exploit beneficial opportunities in respond to climate change.

Mitigation is an anthropogenic intervention to reduce sources of GHGs or enhance sinks of GHGs (carbon sequestration). Thereby reduce impacts of climate change and minimize adaptation challenges. Forest trees, through photosynthesis, remove CO2 from the atmosphere and store it as organic carbon during life of the tree, but when the tree dies and decay or being burnt most of the carbon will be release back to the atmosphere as CO2 (IPCC, 2007).

Hence, the first aim of this study is to assess the level of impacts of climate change on plant production, biodiversity and different ecosystem services, and to understand the responses of plants to change in climate conditions. The second aim is to study different ways of protecting against environmental damages caused by climate change on e.g. agricultural yield reduction, and other socio economic impacts, (so that we are able to minimize the impacts on marketable and non-marketable ecosystem services). The third aim is to discuss activities and options of efficient mitigation and potential adaptation practices by individuals, sectors, institutions and governments, etc.

2. General Overview of Climate Change Global warming and climate change is largely attributed to emission of GHGs from natural or anthropogenic sources and changes in albedo (reflection of radiation from different surfaces to the atmosphere that causes warming or cooling of the planet, with value between 0-1 http://en.wikipedia.org/wiki/Albedo). Climate change is one of the main drivers of terrestrial

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biotic change and has different effects, such as disturbances and loss of habitat, fragmentation, and increasing the incidence of photogenes. In addition, following a change in climate parameters (precipitation change, snow cover, humidity, sea level etc.) there is variation in exchange of different activities in symbiotic, prediction, parasitic and mutualistic relationships (Lepetz et al., 2009). As global mean temperature rise, it causes positive or negative effects on different processes and activities in earth systems (IPCC, 2007) (see Figure 1 and Figure 4). These effects may affect ecosystem services, biodiversity, species composition, plant growth and productivity.

Figure 1 General features of climate change and its impacts on human and earth systems. In this Figure, many activities and processes interlinked with each other, and cause an interrelated effects one after the other (modified from IPCC, 2007 synthesis report).

The effects of climate change have become obvious in the natural environment over the last 30 years, together with other threats like habitat destruction, fragmentation, disturbance and loss

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in biodiversity (Lepetz et al., 2009). For instance, land use change (the most important impact) in tropical forest can cause loss of biodiversity. Hence, overexploitation of natural resources, use of hardwood timber and forest clearing causes high loss in the amount and availability of habitats, and to extinction of species, especially which are endangered, and restricted in range.

Although it is difficult to make a causal link between changes of climate in relation to change in species richness, due to many other variables are also involved (Morris, 2010), species can interact both directly and indirectly and in most cases, indirect interaction is unpredictable(Yodzis, 2000, Montoya et al, 2005 & Morris, 2010). Climate change affects species indirectly by reducing the amount and availability of habitats and by eliminating species that are essential to the species in question (Morris, 2010). As a result, the loss of one species can result in decrease, increase or extinction of other apparently unconnected species; however, human activities are causing secondary extinction at higher level than expected from random species losses. When species are lost from an ecosystem, it is not the only species that is lost, but the interaction and the general ecological functions, which we expect from these interactions, will be also lost (Morris, 2010) (see Figure 1).

According to FAO (2007) and Minura, (2010) climate change impacts classified into two broad categories; 1) Biophysical impacts: indicates the physical impacts caused by climate change directly in physical environment; example, drought and flooding, causes an effect on physical environment such as a) effects on quality and quantity of crops, pasture, forest and livestock. b) Change in natural resources quality and quantity of soil, land and water resources. c) Increased weed and insect pest challenges due to climate change. d) Shift in spatial and temporal distribution of impacts, (sea level rise, change in ocean salinity, and sea temperature rise causing fish to inhabit different ranges). 2) Socio economic impacts: following the first biophysical impacts on environment there will be a secondary effect on socio economic systems. E.g. decline in yield and production, reduced marginal GDP from agriculture sector, fluctuation of world market price, change in geographical distribution of trade regimes, due to shortage of food in quality and quantity the number of people in hunger and risk increased, and cause migration.

2.1 Causes for climate change Due to increasing world population and industrial development there is an increased emission of GHGs. Use of fossil fuels, deforestation, burning and decay of biomass, etc., leads to higher atmospheric CO2 concentration, which currently is around 388 ppm (see Table 1 and Figure 2) and predicted to increase to approximately 470 – 570 ppm until year 2050 (IPCC, 2007). The level of absorption, scattering and emission of radiation with in the atmosphere, ocean and at the earth surface highly affected by the amount of concentration of atmospheric GHGs, aerosols, soli type and moisture, vegetation and land cover, solar radiation etc. They are a cause

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for alteration of energy balance (positive or negative change) within the climate system and are driver of climate change (IPCC, 2007).

Table 1 Major greenhouse gases, current level, global warming potential and their lifetime in the atmosphere. Source: IPCC (2007), http://cdiac.ornl.gov/pns/current_ghg.html [accessed, 13 Sep 2011].

Greenhouse gases

Atmospheric life-time

Recent level(b) Global Warming Potential (in 100 yrs.) time zone(c)

Main source

CO2 ~100(a) yrs. 389 ppm 1 (Anthropogenic activities, fossil fuel use…etc).

CH4 12 yrs. 1748-1870 ppb

25 Wet rice paddies field, wastes, livestock…etc.

N2O 114 yrs. 323 ppb 298 Agriculture, industry and combustion...etc.

CFCs 12-100 yrs. 75-534 ppt 5000-10,900

Industries, old air conditioner & refrigerators…etc.

O3(d) Hours to days 34 ppb n. a. Fuel combustion, organic

compound evaporation…etc.

(a) It is variable and difficult to mention specific atmospheric lifetime for CO2, but mostly around 100 years is accepted. (b) The current level of GHGs in the atmosphere is mentioned in parts per million (ppm), parts per billion (ppb), and parts per trillion (ppt). (c) GWP (Global warming potential) refers to the amount of heat trapped by GHGs in the atmosphere. For instance when we say a 100 years GWP of CH4 is 25, we mean that if we expose the same amount of CH4 and CO2 in the atmosphere, CH4 will have 25 times higher potential in trapping heat than CO2 within 100 years interval.

(d) Tropospheric ozone.

In addition to other factors, the concentration and lifetime of greenhouse gases (GHGs) in the atmosphere depends on the rate of chemical reactions in the atmosphere (faster or slower). For instance, CH4 primarily removed by reacting with hydroxyl radicals to form water and CO2 within its lifetime of 12 years. The global warming potential of CH4 is 72 times higher than CO2 over a period of 20 years and 25 times higher over a period of 100 years. However, since the current concentration of CH4 in the atmosphere is much lower, compared to the level of CO2 (Table 1) the total warming effect of CO2 is higher. According to the Inter Governmental Panel on Climate Change (IPCC) 2007 synthesis report, we can observe in Fig 2, the level of main anthropogenic

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GHGs emissions at global scale. From the total anthropogenic GHGs emission in 2004, (The amount of CO2 emitted due to use of fossil fuel 56.6%, from biomass burning and deforestation 17.3%, CO2 from others 2.8% ) from total anthropogenic GHGs emission CO2 represented to a sum of about 77%, CH4 (methane) 14.3 % produced from livestock, wet rice paddy field, different fermentation processes or (agriculture) energy and waste. From total anthropogenic emission in 2004, 7.9 % of N2O (nitrous oxide) produced due to human activities in agriculture (use of ammonia based fertilizer), due to combustion of hydrocarbon fuel, and from the total anthropogenic GHGs emission in 2004, 1.1 % of F-gases (includes hydroflurocarbon, sulpherhexafluoride, perfluorocarbon, etc.) Produced from industrial activities, use of old air conditioners and refrigerators (see Figure 2).

Figure 2 Global average anthropogenic GHG emission levels in 2004 in terms of CO2-eq. The numerical value in the Figure consists with reporting under emission covered by UNFCCC, Source: IPCC synthesis report (2007). (a) F-gases includes Hydrofluorocarbons (HFCs), Sulphurhexafluoride (SF6) and per fluorocarbon (PFCs)

Different sectors contribute to emission of GHGs with highest proportion from energy sector followed by industry, forestry (including deforestation), agriculture, and transport sectors (Figure 3) causes the overall anthropogenic impact on climate change.

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Figure 3 The main sectors, which take part in global anthropogenic GHGs emission: source IPCC synthesis report (2007).

2.2 Effects of climate change on ecosystems and ecosystem services An ecosystem is a dynamic complex system of plant, animal, and microorganism communities and the non-living environment interacting with each other as a functional unit. Ecosystem services are the benefits that people get from ecosystems, like food, forest products, water quality and quantity, soil conservation, biodiversity, recreation, and other cultural values. In order to get good ecosystem services for human wellbeing there should be a mechanism, which maintain the nutrient cycles, production, soil formation, etc. in a good state, furthermore enhancing sustainability and conservation of natural as well as human made ecosystems is important. Any disruption or loss of natural ecosystems leads to breakdown of ecosystem functioning and causes loss of ecosystem services. Because of climate change (increased extreme events, e.g. drought and forest fire) large proportion of species are at risk of distinction. Here we can include the water purification by wetlands, provided by forest, the protection of coastal areas from storm surges by mangroves and coral reefs, the regulation of pests and diseases and the recycling of waste nutrients, the removal of carbon from the atmosphere (Warren, 2011).

A fundamental difference between global ecosystems of the past and in the future is the dominating influence of human activity and intervention in natural environment, in addition, deforestation, agriculture and over grazing can fasten the processes of desertification especially in sub tropics and semiarid lands (Bolin et al., 1989).

If we observe the function of natural ecosystems and take few example in USA, at least half of the medicines used today derive from natural source. Between 1998 and 2002, one hundred

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sixteen out of 158 new medicine drugs licensed obtained from natural origin and only one percent of known plants analyzed for their potential of use in medicine (Warren, 2011).

Ecosystems and ecosystem services affected by global climate change, both directly and indirectly. Many studies particularly on agricultural crops and forest shows that the enhanced atmospheric CO2 directly increase productivity, because higher ambient CO2 concentration stimulates net photosynthetic activity which have been called ´CO2-fertilization` effect. Transpiration decreases through a partial stomatal closure resulting in increased water use efficiency of plants at least at a leaf scale; nevertheless, there are considerable differences between different species regarding their response. Some species in terrestrial ecosystems may in the long-term indirectly react negatively, perhaps fatal, to increased CO2 concentration. The indirect responses of ecosystems are due to the effect of elevated CO2 concentration is through effect on climate, such as change in temperature or radiation, humidity, precipitation or other climate variables. In most cases, this situation (the change in climate variables) can cause an impact on ecosystems (Bolin et al., 1989).

As environmental exploitations by humans are increased, the global environmental change (GEC) (increasing atmospheric CO2 levels and associated climate changes fragmentation and loss of natural habitats) will also increase, which leads to rapid change on ecosystems in the world. Despite the large body of research showing effects of GEC on population abundances, community composition, and organismal physiology, GEC may cause less obvious alterations to the networks of interactions among species. Yet complex networks of biotic interactions such as predation, parasitism and pollination play an important role in the maintenance of biodiversity, mediation of ecosystem responses to GEC, and the stability (resistance or resilience) of those ecosystem services on which human well-being is dependent (Tylianakis et al., 2008).

The uptake of minerals, nutrient and water, canopy exchange of plants, absorption of light energy for the formation of carbohydrate through photosynthesis reactions as well as the breakdown and burning processes of carbohydrate for growth and development of the plant (respiration) is highly dependent on the amount of atmospheric CO2 concentration and ambient temperature. The processes of transpiration (affected by the opening and closure of stomata), and evaporation from surface of plants determined by the level of temperature and CO2. Soil biotic processes e.g. decomposition, mineralization, immobilization, and soil abiotic processes such as solute transport, weathering, cat ion exchange, etc. in the soil affected by climate change. As a result, it causes a change in net primary production, species composition and resource competition; consequently, the general services, which we get from forest ecosystem; such as forest products, biodiversity, species composition, soil and water resources and recreation are affected (see Figure 4).

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Figure 4 Schematic diagram showing the most important biogeochemical processes in plants and forest ecosystems affected by climate change (Modified from Lukac et al., 2010).

2.2.1 Precipitation Change Global warming causes higher evaporation rates and therefore, higher precipitation rates, but a large general increase in precipitation is not expected, there will be some regions on the globe where the precipitation will increase and others where it will decrease. According to IPCC (2007), more rain expected in the equatorial belt (humid tropics) and at higher-latitudes. While less precipitation projected at mid-latitudes, semiarid areas and dry tropics. The spatial extent of severe soil moisture deficits and frequency of short-term drought (due to shortage and absence of expected rain water for a short period of time) is expected to double until late 21st century and long-term drought become three times more common especially in regions with less precipitation (IPCC, 2007 and Fussel, 2009).

2.2.2 Rise in Temperature Warming of the earth do not uniformly distributed over the world; continents show more rapid temperature increase as compared to oceans. Temperature change will have very different impacts on vegetation and ecosystem productivity, structure and composition depending on the

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actual temperature range at the location (Morison & Lawrol 1999). Global temperature has increased about 0.2oC per decade for the past 30 years and warming is larger in the western equatorial pacific than in the eastern equatorial pacific over the past century (IPCC, 2007).

Regional warming predicted to increase with increasing latitude. However, when we see warming in tropics, although relatively small in its magnitude, it is likely to have consequences on ecosystems, because of the warming effect dry ecosystems become drier, since tropical species are relatively sensitive to temperature change as they currently are living very close to their optimal temperature level. These results imply that the greatest extinction risks from global warming may be in tropics, where biological diversity is also greatest (Fussel, 2009).

Temperature can affect photosynthesis through modulation of the rates of activities of photosynthetic enzymes and the electron transport chain and indirectly through leaf temperatures defining the magnitude of the leaf–to-air vapor pressure difference, which is a key factor influencing stomata conductance. Unlike the temperature sensitivity of processes like flowering and fruiting many other physiological processes have small genotypic variations, although some genetic adaptation have been observed on enzymes like Rubisco (Lloyd & Farquhar, 2008).

3. Plant Responses to Climate change Plants are grouped in to ´C3`, ´C4` and ´CAM` plants according to their photosynthetic metabolic pathways. Around 95 % of the world plant biomass grouped in ´C3` plant species (e.g. wheat, rice, fruits & vegetables), C4 (e.g. maize or corn, sugarcane & sorghum) and CAM (e. g. Pineapple). These divisions into groups largely based on the enzymes involved in photosynthetic fixation of CO2, namely Rubisco, PEP carboxylase and to some extent carbonic anhydrase, which are significantly different in their response to CO2 enrichment. CO2 together with other minerals can activate Rubisco by binding at a non-catalytic site on the enzyme protein. The process of photorespiration rate is high in C3 plants and the relative proportion of CO2 and O2 inside the leaf determines the rate of photorespiration. In contrast, PEP carboxylase in C4 plants not inhibited by O2 and thus photorespiration is negligible. PEP carboxylase also has a higher effective affinity for CO2 than Rubisco in the absence of O2. Therefore, we would expect higher atmospheric CO2 concentrations to increased photosynthesis and growth of C3 plants but not to the same extent, if any, in C4 plants (Bolin, 1989). The result from experiments done on wild grass species shows that under elevated CO2 condition both C3 and C4 species show increase in the total plant biomass of 44% and 33% respectively, the increased in C3 species was greater in tiller formation whereas in C4 was greater in leaf area. Net CO2 assimilation rates (A), that means (flux of CO2 between leaf and atmosphere through photosynthesis) increased in both C3 and C4 species with 33% and 25% respectively, while, stomatal conductance (Gs)(the ability of

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CO2 entering, or water vapor exiting through the stomata) decreased for C3 and C4 species by 24% and 29%, respectively (Wand et al., 1999).

Many simulation results showed that increased biomass production were observed in both C3 and C4 plants under elevated [CO2]; although the enhancement of shoot production by elevated CO2 varied with temperature and precipitation. In C3 species, the response of NPP to increased temperatures was negative under dry and ambient CO2 condition, but was positive under wet and doubled CO2 condition; whereas, the responses of NPP of C4 species to elevated CO2 was positive under all temperature and precipitation levels particularly at high precipitation level (Chen et al., 1996). Plant growth in elevated atmospheric CO2 has shown to be less vulnerable to drought, maintaining higher growth rate on drought condition than plants under lower CO2. Elevated CO2 also enhances plant resistance to heat, frost stresses, likely reflecting greater concentrations of membrane stabilizing sugars in the tissues and it induces greater nutrient deficiency, and as observed in several studies it leads to accumulation, of secondary carbon rich chemicals such as tannins (Niinemets, 2010).

3.1 Responses of field crops to climate change. Elevated [CO2] leads plants to produce a larger number of mesophyll cell, chloroplasts, longer stems and extended length, diameter and number of large roots, forming good lateral root production with different branching patterns; in some agricultural food crops, resulting in increasing root to shoot ratios under elevated [CO2] (Qaderi & Reid, 2009). The potential of crop productivity increased under an increased in local average temperature range of 1-3oC, but it decreased above this range (IPCC, 2007), probably the reason could be low vernalization, shortened phenological phases decrease in photosynthesis rate, and increased transpiration. ( Qaderi & Reid, 2009).

Elevated CO2 have a positive effect on some annual C3 field crops, such as soybean, peanut, and rice cultivars, etc. Growth and development accelerated throughout the vegetative phase, and before flowering stage started seven days earlier, which contributed to the higher grain yield and change in the chemical composition of the rice grain (Uprety et al., 2010). Some studies also show that a reduction in maize (C4 species) yield occurred under elevated [CO2] condition due to shortened growing period and a yield reduction also recorded in some experiment on winter wheat (C3 species) due to an effect on vernalization period (Alexadrov & Hoogenboom, 2000). Whereas an increase in the yield of spring wheat with 8-10% was observed when water was no limiting; similarly, a cotton crop exposed to free–air CO2 enrichment (FACE) was stimulated and show increased about 48 % of harvestable yield and 37 % of biomass under elevated (550 ppm) [CO2 ] level (Easterling and Apps, 2005). The difference in responses in different ecosystems to elevated CO2 might be due to difference in water, soil, nutrient availability and temperature variation (Chen et al., 1996).

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3.2 Responses of forest trees to climate change. Different processes in plants or forest ecosystems and their interaction with climate variability is complex, due to different response of physical, biological, and chemical processes. An increase in the ambient CO2 concentration could reduce the opening of stomata required to allow a given amount of CO2 to enter in the plant that might reduce transpiration of the trees. These could increase the efficiency of water use by forest plants and increase productivity to some extent (Bolin et al., 1989). Trees are capable of adjusting to a warmer climate, although the response expected from species are different and the effect on photoinhibition and photorespiration are more difficult to generalize (Saxe et al., 2001). As forest trees are characterized by the C3 photosynthetic path way their productivity and demand for nutrient is highly affected by atmospheric CO2 concentration and temperature. The total productivity expected from trees (especially from trees with indeterminate growth) growing under elevated CO2 is larger than estimated in crops (Lukac et al., 2010). Estimated increased production from trees is higher than crops only achieved especially if the combination of absorption and increased nutrient use efficiency is attained (Tylianakis et al., 2008).However, the long-term response of forest to rising level of [CO2] is still uncertain. The current over all response of trees is positive and results from a review of 49 papers on effects of elevated CO2 on different tree species shows that net primary production (NPP, photosynthesis minus plant respiration) on average increased with 23 % at an elevated CO2 concentration of 550 ppm as compared with 370 ppm (Norby et al., 2005). Whereas, enhanced in temperatures can lead to heat and more water logging stress in bogs and cause more severe heat, drought and photo-inhibition stress periods in temperate bog and forest ecosystems (Niinemets, 2010).

3.3 Photosynthesis and plant respiration processes. Respiration can be highly affected by temperature (Atkin et al., 2005), and its rate is determined by status of carbohydrate and supply of adenylate (enzyme catalyzing the conversion processes). The sucrose content of the tissue can govern the capacity of mitochondrial respiration (Farrar & Williams, 1991), and mitochondrial respiration plays a great role in growth and survival of plants (Atkin et al., 2005). One would expect at least a short period increases in respiration rate from parts of plants those show increased growth and assimilation due to elevated [CO2], that is source leaves, individual sink tissue (fruit, seed, steam, root etc.) and total sink tissue. Nevertheless, a few reports concluded that long-term treatment with increased concentration of CO2 resulted in declined whole-plant respiration (Farrar & Williams, 1991). Whereas, result of a few other experiments show that a short-term increase in temperature on plants growing in cold climate areas such as Arctic have resulted in greater potential impact on plant respiration than in plants growing in warmer areas ( tropics) (Atkin & Tjoelker, 2003). One of the reasons might be that tropical plants more acclimate to higher temperatures than the Arctic cold area plants.

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Figure 5(a) Changes in the rate of crop development as a function of temperature, Source: modified from Heidorn (2003). The three curves in the Figure indicate that optimal temperature range differs and depends on the species and crop type.

Figure 5(b) Changes in the rate of photosynthesis and respiration of (C3) crops as a function of temperature (Porter & Semenov, 2005). Photosynthesis is a process, undertaken in green plant cells to produce sugar molecules, by the uptake of CO2 from the atmosphere, sun light energy and water, and during the process oxygen released. Whereas, respiration is a process of oxidation of food or breakdown of sugars and production of energy for maintenance, reproduction, and growth etc., which is undertaken in all living organisms at day and night time by the uptake of O2 and release of CO2 and energy.

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Respiration is necessary for many processes in living organisms; for instance, it is crucial for maintenance of photosynthesis activity, mainly because of the energy demands of sucrose synthesis. Moreover, it plays a role in determining the carbon budget of individual plants and the concentration of CO2 in the atmosphere; it contributes up to 65% of the total CO2 released to the atmosphere (Atkin et al., 2005).

For a majority of plants as shown in Figure 5(a), growth in relation to temperature at initial stage on base (low) temperature, there is no active plant growth. As temperature increase rapid and optimal growth will follow at (stage 2 and stage 3) respectively, then, as it reaches to maximum tolerable temperature (stage 4) the rate remain constant or starts to decline following rise in temperature.

The Figure in 5(b) indicates that the rates of photosynthesis and R processes initially increases over a temperature range followed by a flat response after which it start to decrease. However, the responses of photosynthesis and respiration differ. For example the light saturated photosynthesis reaction rate of C3 crops such as rice and wheat is at maximum at a temperature range of about 20-32oC, while crop respiration increase over a temperature range of 15-40oC followed by a decline (Figure 5 (b)).

The response of plant respiration to long-term change in temperature is dependent on the level of effects of temperature on plant development, and on other direct and interactive effects of temperature and abiotic factors (e.g. Irradiance, nutrient availability and drought). Evidence shows that the response of respiration to temperature is dynamic, with plant respiration often acclimating to long-term changes in temperature. In addition, both degree of acclimation and value of Q10 (proportional change in respiration with a 10oC increase in temperature) vary in response to the surrounding environment and/or the metabolic condition of the plants. There is variability in Q10 as day and night time temperature varies (e.g. nights are increasing to a higher extent than daytime). The Q10 of leaf R is often not always reduced in the light compared with the Q10 of leaf R in dark, and Q10 values are often lower in water-stressed plants than in their fully- watered counterparts, root and leaves also differ in their Q10 values as upper and lower canopy leaves. Q10 of both root and leaf R dark generally decreased as temperature increased. Rise in [CO2] does not show a predictable, systematic effect on Q10 of dark R of stems root or leaves. Different studies show a variation in the effect of rise atmospheric [CO2] on Q10 value of R above ground plant parts in dark condition, but the overall result indicate that elevated [CO2] has little impact on the average Q10 values (Atkim et al., 2005). However, Q10 dark R is greater in some plants grown under elevated [CO2] for e.g. According to study of Shapiro et al., (2004) both Q10 light and Q10 dark increased in leaves R of Xanthium strumarium. In addition, Zha et al., (2001) shows Q10 value of Pinus sylvestris increased in late stage of needle expansion. Nevertheless, Zha et al., (2005) found that; ‘there is no a statically significant variation in the

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value of Q10 for stem respiration under different conditions (in elevated [CO2], elevated temperature, or the combination of elevated [CO2] and temperature relative to the ambient treatment. Indicating that all treatments did not significantly alter the respiratory responses of the stem of Scots pine to stem temperature’ and in his all treatments Q10 value were much lower in the growing season than in the non-growing season. However, there has been a variation in different literatures results; Overall, Atkim et al (2005) suggests that higher [CO2] does not on average alter the temperature sensitivity of dark R in roots, leaves or shoots.

In most plants as temperature increase with optimal range, the rate of respiration as well as the rate of metabolism increased, because increased respiration results with higher energy available, that means as long as nutrients are available the metabolism processes within the plant will also increase. Following increased temperature to a certain level, the rate of photosynthesis is also increases but not as much as respiration. That indicates the amount of CO2 produced from increased respiration is faster than the amount of O2 released from increased photosynthesis http://www.ehow.com/info_12002278_plant-respiration-temperature.html [accessed 22/09/2012].

Temperature affect photosynthesis through altering the activities of enzymes, electron transport and leaf temperature (leaf-to air vapor pressure difference) can influence the stomatal conductance. As evaporation increases, stomata tends to close to reduce water loss through transpiration, following this stomata closure reduction in CO2 assimilation rate occur due to less rate of CO2 supply to chloroplast, this is indirect temperature response. Temperature also affects photosynthetic metabolism directly showing a change in the activity of ribulose-1,5- carboxylase oxygenase (Rubisco) processes associated with the regeneration of Rubisco’s substrate, rubulose-1,5- bisphosphate (RuBP) through the Calvin cycle (Lloyd & Farquhar, 2008).

Climatic variability affects crop development and yield via linear and non-linear response to weather variables and exceeding of well-defined crop thresholds, particularly, temperature (Porter & Semenov, 2005). In the processes of plant growth, leaf litter fall to soil ground then under different temperature condition various processes under going inside as well as outside the soil surface and many processes and reactions directly affected by rising temperature, decomposition, weathering and mass flow diffusion etc. may hasten in the soil under optimum soil moisture condition. At low temperatures, the reaction processes become slower, temperature can indirectly affect plant morphology, growth, roots turn over etc., if it is both beyond and under the optimum level for the plants. In addition, soil moisture, availability of nutrient and minerals together with other processes will play an important role in plant growth and development (see Figure 6).

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Figure 6 Direct and indirect effects of a rise in temperature on different component processes in plant and in the soil (Lukac et al., 2010).

Enhanced CO2 and anthropogenic Nitrogen can directly increase short-term plant growth rates and change plant chemistry (C:N ratio and concentration of carbon-based compounds often increase), these physiological changes can affect a range of biotic interactions involving plants. As an example of plant responses, C3 plants often derive a competitive advantage following nitrogen deposition and C4 plants can derive a competitive benefit from increasing temperatures (Tylianakis et al., 2008). Long-term ecosystem responses to elevated CO2 may ultimately depend on nitrogen availability to plants and on the ability of plants to use nitrogen more efficiently under elevated [CO2] condition (Norby et al., 2001). In addition, larger supply of photosynthesis to mycorrhizal fungi shown to occur under elevated CO2 (Lukac et al., 2010).

Nutrient up take by tree is an active process supported by enzyme activity, and is highly dependent on temperature. Several authors claim that nutrient uptake increases with rising temperature, but similar to enzymatic processes, the rate of uptake increases only until a threshold temperature reached. A period of increased soil and air temperature; whether it is gradual or rapid hot and in which stage of the growing seasons, is also an important condition and has a potential factor in the uptake of nutrient. Because of their longevity, trees have developed physiological mechanisms to deal with such disruption and are able to store and re - mobilized nutrients. However, repeated seasonal stress might exhaust this capacity for nutrient storage, with detrimental effects for tree health in the long-run (Lukac et al., 2010). Increased

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decomposition rates of leaf litter could result in more readily mineralized nutrients available to the plants, which likely would increase photosynthetic carbon gain in nutrient limited systems (Boisvenue & Running, 2006).

Two general issues of concern are whether increases in NPP in response to rising CO2 will be sustained if negative feedbacks through the nitrogen cycle occur, and whether decomposition rates will change if atmospheric [CO2 ] affects the chemistry of decomposition (Norby et al., 2001). Most of the nutrients, with some few exceptions, can be transported both upward ( xylem flow) and down wards (phloem flow) within a tree, this cycle of nutrient have shown to be affected by heat and drought and thus influencing above ground biomass accumulation of some elements. Such direct effect of temperature on tree physiology and metabolism are likely to vary between species and element specific (Lukac et al., 2010).

3.4 Agriculture and climate change Agriculture contributes to climate GHGs emission (see Chapter 2) and highly affected by change in climate parameters. In an intensive farming, we expect high greenhouse gases emission because of using high amount of inputs and chemicals, due to these changes of human activity natural divers and climate change impacts varies accordingly in different part of the world.

Vulnerability to climate change depends not only on physical and biological responses but also on socio economic characteristics. Low- income population especially those who cultivate crops under rain fed and non- irrigated agriculture systems in dry lands, arid and semi-arid areas highly affected by severe hard ship due to climate change (Grasty, 1999).

3.4.1 Climate variables and productivity According to suggestion of fourth assessment report of IPCC, (2007) The overall impacts of higher temperatures on crop responses at the plot level, without considering changes in the frequency of extreme events, moderate warming. (I.e. in the first half of this 21st century) may benefit in crop and pasture productivity in temperate regions, while it may reduce productivity in tropical and semi-arid regions. Modelling studies indicate small beneficial effect in temperate corresponds to local mean temperature increases in 1-3oC with association of an increased in CO2 and rainfall changes. In contrast, models show that tropical regions show a negative yield impacts for major crops with moderate rise in temperature (1-2oC), but further warming projected in all regions in the end of twenty-first century results in the increased on negative impacts (Tubiello et al., 2008).

Due to impacts of climate change, agricultural productivity directly affected in developed and developing world (Alexandrov & Hoogenboom, 2000). Climate plays a major role in determining the yield level by increasing or reducing in global perspective from temperate to tropics. Many experiments show that CO2 is a limiting factor, in which higher concentration of CO2 enhances

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photosynthesis and crop growth, modifying water and nutrient cycles (Tubiello et al., 2008), these responses found to hold even for plants grown under different stressful conditions. Despite related to generalization of the law of `limiting factors´ when other environmental factors such as water shortage, less light, shortage or excess of minerals, very high or very low temperature limit yield, then CO2 concentration will have little or no effect. Nevertheless, in certain stressful environments the relative photosynthetic response of plants to CO2 enrichment is actually increased (Bolin et al., 1989).

For most crops, growing under elevated CO2 conditions both quality and total yield shows improved (more ear of plant per m2). The increased CO2 induce and makes an increase in the grain weight and according to the observation, it was greater under average phosphorus treatment compared to higher phosphorus level. This influence of CO2 and phosphorus supply was attributed to increase in the number of cells within endosperm, which is the result of enhanced rate of cell division during grain development or by greater amount of grain filling during ripening phase (Uprety et al., 2010). However, it has also been shown that elevated CO2 concentrations may have negative effects on the grain quality from wheat in terms of protein content (Pleijel and Uddling, 2012), it alters wheat grain lipids and doubled the number of mitochondria in wheat leaves, lower seed nitrogen concentration and decreases grain and flower protein (Qaderi & Reid, 2009).

3.4.2 Direct effects of climate change on food crops Food production can be negatively or positively affected following variation in weather patterns (short winter, long summer, earlier spring) and other extreme weather events such as drought ( change in amount and timing of precipitation), flooding, etc. In addition, illegal deforestation can cause reduction in crop production, due to its effect on environmental services such as crop pollination, genetic resources, clean air and water supply, soil fertility and erosion, as well as pests and pathogen control (Cerri et al., 2007).

3.4.3 Indirect effect of temperature Several studies shown that soil warming can affect availability of nutrient, increase soil N mineralization and nitrate leaching, organic matter decomposition, and a slight temperature increase can produce a significant enhancement of activities. An increase in N mineralization in soil can be predicted under favourable moisture conditions and substrate availability, mainly in those ecosystems where temperature is a limiting factor, which leads to increased NPP (net primary production), increased N demand and ultimately to decrease N availability in the soil. An increasing temperature will also speed up the release of nutrients locked up in organic soil fraction and minerals, while decreasing soil moisture may limit this process. A higher rate of weathering of nutrient rich rocks generally leads to higher base saturation of the soil and

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maintain higher soil pH, both characteristics favourable to plant growth. While elevated CO2 not thought to have a direct effect on weathering (Lukac et al., 2010).

Plant species distribution limited not only by their absolute limits of survival, but also through competition within species, which species acclimate and grow better in a given climate. In the context of population extinction, it is important to consider the effects during climate events. Temporal variability in environment commonly believed to increase the probability of population extinction, particularly if environmental variability increases due to climate change. Some evidence suggest that climate change already drives the extinction of rear edge plant populations leading to a distribution with a ´trailing` edge. Some desert trees like Aloe dichotoma in southern Africa the trailing edge of the range, making populations showed negative demographic rates, and strongly positive rates observed at the leading edge of the range making population growth rate sensitive and use full indicator of incipient change in range (Thuiller et al., 2008).

3.4.4 Impacts of temperature × [CO2] interaction on plant processes There are many processes in plant growth, affected by interaction of both enhanced temperature and carbon dioxide, in processes that determine carbon balance in the shorter term, from the long time scales of development and growth, which together lead to accumulation of biomass and yield. The two main reasons to expect progressively increasing CO2 responsiveness of plant carbon balance at higher temperatures are 1) the decreased ratio of photosynthesis to photorespiration and 2) the decreased ratio of gross photosynthesis to dark respiration in warmer conditions (Morison & Lawlor, 1999).

The effect of elevated CO2 on photosynthetic reactions are more pronounced in high temperature, e.g. around 20oC than at 10oC. Some predictions indicate that future increase in temperature may increase root mortality more in N-rich soils in temperate forests than in N-poor soils in boreal forests areas with important implications for the cycling between plant and soil (Lukac et al., 2010). Some (unpublished) studies found that changes in activation state and catalytic constant occur due to both CO2 and temperature, and there were an interaction, which affected the photosynthetic rate demonstrating the underlying complexity of the photosynthetic regulation mechanisms (Morison & Lawlor, 1999).

To sum up, environmental change has an impact on growth rate of individual trees and have a cumulative effect on different interactions and processes inside the forest and has the ability to change the amount of living materials in the forest ecosystem as a whole (Lukac et al., 2010). Temperature is one of the decisive factors in forming an effect on growth and productivity by accelerating the bud burst (BB), flowering, and stems elongation during spring and then extend growing season, and it is one of the major factors controlling species distribution. For instance,

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the predicted warming of 2- 6oC by 2100 in north temperate forest regions could have substantial impacts on growth and species composition (Gunderson, 2012).

Increasing temperatures mostly associate with elevated CO2, vapor pressure deficit (VPD) and drought. Change in temperature will interact with other factors to form an effect; for e.g. nitrogen fixing nodule bacteria, mycorrhizal fungi and many other processes influenced by rising temperature. The long-term responses of climate change under higher CO2 concentration, temperature and precipitation may differ from short-term effects because of the feedbacks involving nutrient cycling (Chen, 1994). ‘Tree seedlings exposed in elevated [CO2] over time period of less than 1 year resulted in enhanced rate of photosynthesis, decreased in respiration and increased growth, with little increased in leaf area and small variation in carbon allocation. Exposure of woody species in elevated CO2 over long time-period may result with higher rates of photosynthesis, but net carbon accumulation may not necessarily increase if CO2 release from soil respiration increases’ (Luxmoore et al., 1993).

Environmental shift affects the extent of plant diseases and insect pests both the presently occurrence and infestation, introduced of the new species. Following these changes, a number of diseases, pests and weeds, preventing actions needed to reduce the effects on human health and ecosystems (Roos et al., 2010).

Different chemical, biological and physical processes in earth systems need various temperature ranges; usually moderate and optimal temperature (for each processes) are essential for normal activities within the systems, a certain rise or lower from moderate temperature will affect many activities within the processes.

4. Adaptation Measures for Climate Change

4.1 General overview

4.1.1 Definition According to dictionaries the term adaptation refers to make more suitable (to fit some purpose) by modifying (or altering) and it indicates both the process of adapting and the condition of being adapted. In ecology, adaptation indicates change in an organism´s physiology, behavior or other characteristics that increase the fitness to the environment, related to genetic changes. In social science, cultural adaptation refers to adjustment by individuals and to the collective behavior of socio-economic systems. Cultural adaptation also include changes in cognitions (e.g. risk perceptions), which are socially constructed and negotiated (Grothmann & Patt, 2003). Adaptation to climate change refers both making use of 1) the ecological adaptation and its relation to the environment by ecosystem management and 2) the change in social behavior to reduce the impacts of climate change. Thus, adaptation to

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climate change is the process through which people reduce the adverse effects of climate on their health and well-being, and take advantage of the opportunities that their climatic environment provides (Smit et al., 2000; Glick et al., 2009).

The term “adaptation” has been used since the early 1990´s in the climate change context. No specific single definition is given to it, but most definitions reflect that climate adaptation involves “initiatives and measures to reduce the vulnerability of natural and human systems against actual or expected climate change effects” (Glick et al., 2009). Another definition of adaptation involves adjustment to enhance the viability of social and economic activities and to reduce their vulnerability to climate, including its current variability and extreme events as well as long-term climate changes (Smit et al., 2000). According to Grothmann & Patt, (2003), the action taken by people to avoid impacts or to be benefit from opportunities associated with climate change, we call this adaptation.

Natural resource conservationist propose the following definition “climate change adaptation for natural systems is a management strategy that involves identification, preparation for, and responses to expected climate change in order to promote ecological resilience, maintain ecological function, and provide necessary elements to support biodiversity and sustainable ecosystem services”. In general the term climate change adaptation can be concluded by the following phrases; “climate change safe guards”, “preparing for warming world”, “protecting wild life and natural resource from warm” and “coping mechanisms”(Glick et al, 2009).

4.1.2 Importance of adaptation Why do we need adaptation? Adaptation is important in the climate change issue in two ways; one relating to the assessment of impacts and vulnerabilities, the other is to the development and evaluation of response options (Grothmann & Patt, 2003). The danger and seriousness of climate change can be changed or reduced through practicing different kinds of adaptation measures, and adaptation is crucial in policymaking and planning strategies. During planning, considering different weather events and climate variables and collecting required information is important to prepare in advance and to decide the kind of measures, how and under what conditions adaptation practices can be performed (Smit et al., 2000). Depending on degree of spontaneity, either adaptation can effectively planned or performed autonomously. Planned adaptations largely related with public agencies and autonomous adaptation with private sectors. Planned adaptation increases adaptive capacity by mobilizing institutions and policies to establish or strengthen conditions that are favourable to effective adaptation and investment in new technologies and infrastructures. Autonomous adaptation is the ongoing implementation of existing technologies and knowledge in response to changes in climate experiences (Rahman, 2008).

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Adaptation measures can take technological, economic, legal and institutional forms. For both assessment and implementation of adaptation, it is important to know the form of adaptation and the condition under which it might expect to occur (Smit et al., 2000). Both community and individual have to deal with different extremes or weather events like flood, storms and drought. Autonomous adaptations are useful, especially for smallholder farmers, which includes using resistance varieties and different inputs, changing the rate of application of fertilizer to approve quality of agricultural products. Using different water management practices, e.g. in low rainfall areas, improving water-holding capacity of the soil and collecting water to conserve moisture of the soil, making physical soil and water conservation structures, and changing the amount and timing of irrigation (see also Table 3). In area where there is excess rainfall, preventing logging and leaching of nutrient by erosion. Using weather forecast information to reduce the risk of climate events, such as, early warning about drought or outbreak of disease and pest in every season. Adjusting timing of cultural practices, diversification (creating more income mechanism from forestry, agriculture, etc.) e.g. poultry production, beekeeping, livestock’s fattening, and other small agro-industries activities.

Using technical options include many forms of land use, land use changes, new cultivation techniques. Planned approach must include appropriate incentive structures, such as payment for environment services, in a way that can expand the options for indigenous people and poor communities to be beneficial in both mitigation and adaptation (Rahman, 2008).

Adaptation includes different actions throughout society, individuals, groups and governments, which can be manifested and motivated by different factors, through actions of individuals, organizations to meet their goals, can be taken by government to protect the citizens, or by individual for their own benefit (Adger et al., 2005).

Adaptation to climate variability aims to reduce vulnerability or increase resilience (improving ability to tackle and recover quickly from observed or expected climate change difficulties and weather events). Adaptation of physical, ecological and human systems include a change in social and environmental processes, and practices, enabling reduce potential damage or finding new opportunities. Adaptation includes anticipatory and reactive actions, to expected change in temperature and climate variations and extremes. In practice, it should be on-going processes, which reflect many stresses. For example, crop and livelihood diversification, seasonal climate forecasting, and many activities including community based disaster risk reduction, water storage, and supplementary irrigation etc. Individuals undertake some adaptation measures and others may be planned and implemented by government on behalf of the society. In some cases, it is expensive to implement adaptation measures (Adger et al., 2007).

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4.1.3 Dimension of adaptation According to Food and Agricultural Organization (FAO) of the United Nations (2007), climate change adaptation will be necessary in a variety of ecosystems, such as crops, livestock, grasslands, forestry and woodlands, inland waters etc., and adaptation measures can differ according to several dimensions: (A) by spatial scale; local, regional and national, (B) by sectors; water resources, agriculture, tourism, and public health, etc, (C) By the type of actions; physical, technological, investment, regulatory and market, (D) practices by stakeholders; national, government, private sector, local communities, NGOs, and donors, (E) by climatic zone; arid land, dry land, arctic, floodplain or mountains etc and (F) by the income level; developed, middle and least developing countries. It also differs by the combination of these and other categories. From a temporal scale, adaptation viewed at three levels, which include current variability (learning from past adaptations to historical climate), observed medium and long-term trends in climate and anticipatory planning in response to model-based scenarios of long-term climate change. The research on vulnerability and adaptive capacity shows that some dimensions are generic, while others are specific to particular climate change impacts. Generic factors include education, income, health, and indicators specific to an impact such as drought or floods and may be relate to institution knowledge and/or technology. Technology play an important role in adapting to climate variability, for example seed improvement through plant breeding, cooling systems and other technologies and engineering solution are able to lead to improvement of the outcome and ability to cope with climate change conditions (Adger et al., 2007).

In regions where water resources are already scarce and likely to become increasingly so due to high demand by growing human population, the impact of climate change become serious on river and stream ecosystems. Furthermore, humans have made changes in some of rivers and streams, because of a number of factors including construction of dams, water diversions for agriculture and other structures, destruction of riparian vegetation and pollution of water, etc. has significantly reduced the rivers and streams resistance capacity and their resilience to the impacts of climate change (Glick et al., 2009).

4.1.4 Steps in adaptation Whatever the level of technologies that are available, its application is likely to be a more successive process rather than an on and off activity (Figure 7). Stalker (2006) suggested the successive implementation to be conducted in the following four main steps. Firstly, adaptation measures needs to collect, interpret necessary information, and forming awareness. Secondly, assessing and formulating different adaptation options and finding or assigning stakeholders will be the next step in planning before implementing the options. It needs to design in appropriate way, and should be not only technically feasible but also is consistent with the country´s development objectives as well as some key policy criteria. The technology needs to

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be reasonably cost effective, environmentally sustainable, culturally compatible, and socially acceptable. The third step is implementing actively supported by effective institutions, from national organizations up to individual communities. Finally, the technologies, which are already available needs to monitor, evaluate, follow up and make them more effective, and modified.

Figure 7 Steps in planned adaptation to climate change, modified from (Stalker, ed., 2006).

For the purpose of mitigation, transferring technologies (ideas or equipment) from developed country to developing countries is necessary. However, technologies for adaptation differ from those for mitigation, because adaptation is not only concentrated in one sector, but also dispersed across all socio-economic sectors including agriculture, water, health, and infrastructure, so in a number of respects adaptation is divers and more complex than mitigation (Stalker, 2006).

Adaptation measures can be site specific and target oriented, but if it is not properly planned and performed, it may cause a negative impact for the poorest people and those with insecure access to land. Similarly, some adaptation actions may cause a competition of resource; for example, to increase plant productivity we may need to use high amount of water for irrigation, and this may affect those who have no other alternative or access to irrigation schemes. Some adaptation measures may increase the demand of land that affects land less or small landowners, by making the price of the land higher. Such potential outcomes make adaptation

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complex and variable (Rahman, 2008). In addition, adaptation measures should be less capital intensive and more suitable to small scale interventions that needs to be more flexible and adaptable to local community and may therefore be more socially and legally accepted. However, as any type of technologies, there is always a risk that adaptation measures will be more accessible to rich communities. Therefore, Policy makers need to ensure that new forms of adaptation do not increase inequality, but rather contribute to a reduction in poverty (Stalker, ed., 2006).

4.1.5 Evaluation of adaptation According to Preston et al (2010), it is important to evaluate adaptation processes during implementation phase, (see Figure 7) mainly due to the following reasons. a) Ensuring the community and natural vulnerability, since one of the main aim of climate adaptation is reduction of human and natural systems vulnerability (to avoid or reduce the effect of dangerous climate change). In practice, the evaluation has to ensure the social, economic and environmental benefits of adaptation policies and measures outweigh the costs and additional approving the avoidance of negative externality. b) Approving social learning and adaptive management, institutions can identify effective, efficient, and equitable policies and measures, checking the success or failure of different adaptation initiatives, getting a chance of learning by evaluating adaptation, transferring knowledge and sharing experiences. c) needs of accountability in an evidence-based policy environment, the investment in adaptation and the outcomes should be transparent for every aspects of adaptation process, risk assessment; it can be reform of planning policy, or infrastructure upgrades.

4.2 Adaptation options So far, only limited adaptation measures considering climate change has been undertaken, in both developed and developing countries. These adaptation measures undertaken by sectors are using different technologies to prevent environmental damages (Adger et al., 2007). In Table 2, examples of possible adaptation measures in agriculture, forestry, energy and recreation sectors, in response to change in the mean temperature and precipitation level in different seasons are presented. In many cases, people adapt to climate change by changing their behaviours, changing their occupation, by moving to different location, or often they may use different forms of technologies. These can either be “hard” technologies; such as using new irrigation systems, drought resistant crop varieties, new introduced insect and pest resistance varieties and using the result of other new breeding techniques. For e.g. using products from techniques of plant biotechnology and genetic modification, (a method which discovers specific gene, how they work, and identify traits and transfer gene where they are needed) or “soft” technologies; for instance, insurances, other services and crop rotation or they could use the combination of hard and soft (Stalker, 2006).

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Table 2 Adaptation options implemented by private and public sectors, modified from (Mendolsohn, 2000).

Sectors Public or Private Adaptation measures

Agriculture Private Alter crop species, change timing of agricultural or cultural practices, using Irrigation

Public Plant breeding /producing improved varieties

Sea level Private Depreciate vulnerable buildings

Public Sea wall as needed, beach enrichment

Forestry Private Harvest trees which are vulnerable, Planting new trees, intensify management

Energy Private Cool building designs, change in insulation, use new cooling methods,

Public using new building codes

Water Private Working on Water efficiency

Public Shift water to high value uses, Collecting & storing water, flood controlling

Biodiversity Public Moving endangered species, managing landscapes,

Planting more adapted species

Aesthetics Private Behavioral adaptation (e.g., recreation)

Public educate community about adaptive options/ awareness

4.3 Private adaptations Private adaptation is normally a behavioural response by a company, or private person to an environmental change that primarily is for his/her own benefit, but might be linked to societal benefits. The likeliness of private adaptations will decrease with uncertainty about the future benefits of adaptation and with uncertainty about the costs. In order to predict future benefits individual needs not only to predict the local future climate change and understand what type of impact it will have, but also what kind of actions that potentially can be taken to counteract the effects. However, it will be difficult for private persons to make prediction and it is not easy to reach knowledge and information from few experts in the world to the majority of individuals, especially to those poor at rural level (Mendelsohn, 2000). Practicing adaptation measure to climate change often means approving good sustainable development (Simoes, 2010).

Adaptation can be short run or long run, using fixed capital to make some adjustment can form a limited behavioural change in short run; whereas, in long run all changes can be made in

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factories, buildings, and transportation system etc. Behavioural adaptation of communities in flood- prone areas whenever the risk of an increased flooding damage due to climate change occurred protecting for instance by building higher houses to reduce the damage of flood might be used as a solution (Grothmann & Patt, 2003).

Many study suggest that farmers can readily adapt to changes in the mean temperature, and if not, also farms can be dramatically damaged by increases in inter annual variations. Examples of adaptations to slightly warming condition are; plantation of more suitable and warm loving crops (Figure 8), sowing or planting earlier, double cropping, using irrigation, water harvest etc. However, if the variation of warm and cool is exchanging in short period of few years, then, there will be no single crop appropriate for all out comes (Mendelsohn, 2000).

Different crops prefer different climates, some cooler, and others warmer; for example, wheat and barley prefer cool climate, maize prefer moderately warm and wet environments and many fruits, some root crops and vegetables prefer warmer condition.

Figure 8 Farmer’s opportunity, in crop choice adaptation, under change in temperature condition, adapted from (Mendelsohn, 2000).

As climate becomes warmer and wetter farmers would try to adjust their choices to the new weather conditions (Fig. 8). Farms in the areas of wheat regions may switch to maize, farms in maize regions could possibly switch to some fruit crops and farms in the warmest fruit region potentially have a choice of growing many subtropical crops. These mechanisms of efficient adaptations can reduce the damage that takes place following climate change. If farmers

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continue to produce the same crop in increased warming condition, the result could be highly losses in production. To prepare in advance and use different options, reaching weather information, collecting climate data and improving awareness of the rural poor individual farmers and the whole community is important. Through switching crops, which are more suitable to new climate condition farmers are able to reduce potential damages, and in some cases, they might get a chance to be beneficial for e.g. by producing some cash crops, which are suitable to the changing condition.

Spontaneous adaptations considered those, which are undertaken by private sectors, invariably in reactive response after initial impacts are manifest to climatic stimuli without direct intervention of public agency (Grothmann & Patt, 2003). According to Mendelsohn (2000), private adaptation will tend to be efficient because decision makers support the cost and rewards. Private decision-makers can leave to his own devices to make an efficient choice, there is no government policy required. However, there should be some technical advice and support, guiding private adaptations to be more efficient. In addition, government will be help full if there are externalities in relation to adaptation by encouraging individuals to incorporate the externalities in to their decision-making mechanisms. Collecting and dispersing of future climate would be very useful for farmers or investors who are going to plan to work in short run growing of annual crops, as well as long run for example working on forestry. The foresters can determine the type of tree species, which is suitable and will resist the coming environmental and climatic condition.

4.5 Adaptation strategies for agriculture Agriculture is highly sensitive to even minor climate variations, and have an impact on agricultural output even for a single growing season, so ongoing climate change can affect long-term agricultural productivity and food security (Stalker, 2006). Climate change impacts on crops affect human health, largely through potential for mal nutrition and as a result, few studies have estimated millions of peoples are at risk of hunger (Warren, 2011).

Adaptation is efficient if cost of making efforts is less than the resulting benefits Joint adaptations will be beneficiary only if it is through governmental actions, In addition, political forces are likely encouraged if governments are engaged in inefficient adaptation behaviour, thus, it is not at all clear whether efficient levels of joint adaptation will be undertaken (Mendelsohn, 2000).

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Table 3 Example of adaptation options in agriculture, modified from (Stalked, ed., 2006).The practices, mentioned here are cultural practices; which do not need high capital and most of the options can be easily applicable by individual or group of farmers who are vulnerable to climate change.

Strategy Adaptation options

Using different crops Producing new varieties

Physical land improvement to control soil erosion, improving water holding capacity of the soil

Forming a small catchment for agricultural activities, Covering waterways using grass to protect from runoff, making the land surface rough, making windbreaks and hedge raw in farm fields, using cut off drain, check dams, grass strip, and tillage farming.

Improve water use and sources

Using plastics for canal lines, using ground water, collecting and using run off, focus irrigating in peak growth stage, using water save irrigation system e.g., drip irrigation, use slightly salty water where it is possible.

Making a change in cultural practices in order to maintain nutrient and soil

Using biological conservation measures, such as mulching, crop rotation, tillage farming, double cropping (mixed farming), alley cropping, etc.

Adjusting timing of different farm activities

lowering the plant densities, early planting or sowing to offset moisture stress during warmer condition

Since population increment and industrialization, leads the world to become warmer, we have to perform activities by conserving and utilizing natural resources efficiently by approving sustainable development and try to protect resources and ecosystem services. Our actions of adaptation to climate change should potentially be applicable according to locations and situations of extreme events, and we should target not only livelihoods and farming activity of individual households, but also solving problems in a wider range, working on reduction of poverty and approving food security. We have to increase agricultural food production and overall productivity in intensive way to feed and satisfy the need of increased population.

Agricultural systems are flexible, if farmers get correct information, tools, technical advice and support, they should be able to practice many of the options. However, it might be difficult if the soil quality is poor (less fertile in nutrient), if there is inadequate amount of water or shortage of capital funds for investment, or if farmers face institutional or cultural barriers (Stalker, 2006). In such case, government has to provide new technologies and knowledge with technical and economic support.

Agricultural cropping systems in relation to climate change adaptation require focusing on problem solving of both excess water due to high intensity and lack of water due to extended

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drought periods (FAO, 2007). For both cases, it is necessary to improve soil structure and water holding capacity of the soil.

The benefits from research widely shared and combined between local (traditional), modern techniques of genetic crop improvement and through improved management practice, using irrigation, and other inputs, leads to current yield improvement in some part of the world. Moreover, our technology should consider satisfying the interests of whole sectors, (stakeholders, individual farmers, plant breeders, local communities, and other sectors). Although we have new technologies, which are suitable for local conditions, for poor farmers sometimes it is difficult to adapt, with small farm sizes and limited access to credit, they may have neither the ability nor the possibility to invest in new technology (Stalker, ed., 2006).

When practicing adaptation there is a cross-regional interaction between different regions, the mechanism of climate change impact in one region can directly affect the other, the loss of human or natural capital of one region affect human or natural capital in another region, or indirectly through mitigation or adaptation measures practiced in one region can have a consequence for another. For example, agricultural yield reduction of a certain region can cause an increase in the demand of imported food products from another area these potentially affect the price of food crop products globally (Warren, 2011).

Changes in land use and land cover have large impact on climate change both locally and globally. For example, because of deforestation, surface albedo changed and the amount of carbon released from the soil and deforested vegetation also increased. In addition, forests like Amazon recycle their water, thus, following forest loss, we may end up with drying. Climate change mitigation could involve significant reduction in deforestation, since it is regarded as the most cost effective way of reducing emission, politically there is a consideration of doing that in REDD projects (Reducing Emissions from Deforestation and Degradation) (Warren, 2011). However, human adaptation to climate change impacts might cause shift in agriculture from dry area to forest areas, these can create additional impact on natural ecosystems.

In approving food security, trees and shrubs in agro-forestry and farming systems can play a significant role in mitigating the impacts of extreme events (FAO, 2007). On the other hand, afforestation can also contribute to climate change mitigation through carbon sequestration, causing positive or negative implications for biodiversity and ecosystem services. Creating forests in areas where there is non-forest biodiversity using non-native tree species can have a negative impact on native or local biodiversity. Beyond that, it might not succeed because of the soil and other climatic factors may not be suitable for planting non-native tree species. Mostly focusing on indigenous or local native trees in previously degraded or deforested areas will be beneficial for biodiversity and ecosystem services to enhance connectivity in forest ecosystems. However, it is important to notice that afforestation is a slowly process and it will therefore take

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a long time before a deforested area in terms of carbon storage can be compensated for by afforestation (Warren, 2011).

4. 6 Tools in planning adaptation Adaptation strategies can work in two ways, by reducing vulnerability (susceptibility) to changing condition, or by increasing resiliency (to recovery) by reducing suffering during and immediately after the events (Bedsworth & Hanak, 2010). Below in Table 4 we can see the summaries of adaptation measures for some consideration of changes and reflecting their activities using and sharing their accumulated experience with better coordination.

4.7 Adaptation in terms of some agro ecological aspects Human being changes the environment by using different agricultural production techniques, through these technologies; there is modification and improvement in adaptation. Since adaptation includes a quantitative complex feature of an organism, involving many traits such as developmental, morphological (adventitious or tap root system in plant), behavioral, physiological (accumulation of some chemical compounds), reproductive (prolonged seed viability), etc. In climate, warming condition, for example, for spring crops we may need to sow earlier, that makes crops to increase yield potential by reducing or avoiding chances from the stress factor and lengthening the growing season. If other conditions are in optimum level for the production, early crop cultivars or early sowing might also able to reduce the irrigation required amount of water (Ulukan, 2008).

4.8 Sustainable adaptation measures The physical impacts of climate change in existing programs and activities should consider widely vulnerability to climate change and these activities are necessary in adaptation to contribute in poverty reduction.

Organization and development agencies should focus on risk reduction works, e.g. early warning and moving of people from danger areas. The risks are varying from place to place and between different groups, measures targeted at risks might be very specific to a particular situation. For instance, if we take agricultural productivity reduction caused by climate change stress could potentially targeted to solve through adaptation measures, which will focus in changing cropping pattern techniques and using different modern technologies (Eriksen & O´Brien, 2007). Since different outcomes and adaptation, responses in a certain group may possibly affect the vulnerability context of some other groups somewhere else and adaptation responses might affect socio- environmental transformations, sustainable adaptation (see Table 5) is therefore a global environmental issue (Eriksen, 2009). In planning adaptation and decision-making processes, institutions have to focus on low risk knowledge, on capacity building measures and specific actions to reduce vulnerability, and the critical consideration is not only planning but also implementation of the adaptation processes.

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Table 4 Different tools used in planning and practicing adaptation options to climate change, source (Bedsworth & Hanak, 2010) Area Structural tools Planning or regulatory tools Response tools Market based tools

Ecosystem

Resources

Habitat corridors,

reserve acquisition

Pre-emptive protection of areas to anticipate future species needs

Salvage program (e.g. hatcheries for species threatened with extinction in the wild

Incentives for “ smart growth” land use planning & forward looking conservation planning

Air quality

Different emission control techniques

Stricter emissions standards (overall and for peak episodes), new emission reduction program

Emergency plans (e.g. heat, fire, etc.),

forming a Public awareness campaigns ( e.g. air quality alerts)

Emission and fuel taxes

Water supply

New ground and surface water storage facilities,

making canal around delta, different conservation technologies

Stricter building and plumbing codes, new reservoir operation rules, ground water basin management

Drought response program ( e. g., rationing of water use)

Reallocation of supplies through water marketing &

demand reduction through water pricing

Flood control

Levee and reservoir development, low- impact development

Restrictions on floodplain development, flood insurance mandates,

new reservoir operation rules

Flood evacuation plans

Risk- based insurance premiums

Coastal resources

Coastal protection (e.g., levees, seawalls),

beach nourishment,

artificial drainage systems for low-lying areas

Stricter building and zoning codes, relocation of structures to allow in ward migration of coastal lines,

insurance mandates

Flood and coastal erosion evacuation plans

Risk based insurance premiums

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Tabel 5 Potential adaptation measures, implemented for poverty reduction, modified from Eriksen & O’Brien (2007).

Vulnerability - poverty links Sustainable adaptation measures

Clim

ate

risk

Climate change and variability effect on agricultural production.

Crop diversification, planting wind breaks, national agricultural insurance schemes,

Improvements of early warnings and evacuation procedures.

Income reduction, threatening the poor due to drought and flood, heat waves and cyclones in urban and rural areas, melting of glaciers etc.

Water conservation, construction of wells, and flood controlling etc.

Impacts on energy supply

Improve local renewable energy alternatives.

Damage and shortage of social infrastructure

Making Infrastructure and housing more climate resilient

Sanitation problem due to flooding, occurrence & spread of disease

Making a better health facilities to the poor people

Adap

tive

capa

city

Multi activity and multi locality Multi activity and multi locality

Migration with cattle to access grazing Improve services along livestock migration routes ensure rights to drought grazing areas

An adjustment of crop types Focusing of conservation and research on local strain crop varieties

Forming a social networks & additional income mechanisms

Approve equitable access to important adaptation resources e.g. water, focusing and investing on local adaptation options

Construction of drought water sources and small scale irrigation

Planting indigenous trees and enhances flexible drought access to forest.

Use of forest products

Improve value adding and processing of local forest products

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During flood and drought, especially poor people are more vulnerable, so some adaptation measures e.g. improvement of infrastructure, and water use, etc., have good contribution in coping strategies. The adaptive capacity linkage between vulnerability and poverty emphasizes the importance of multi activity and multi locality in the ways in which people seek to secure well-being. In order to reduce vulnerability of especially the rural poor community, our adaptation measures have to target on the multiple sectors and different fields in which people are interested to participate. In some cases, sustainable adaptation measures need consideration and a support from civil society by strengthening collective management of the resources that are very important for local coping and adaptive strategies. Furthermore, for sustainable adaptation in some places it is practiced that democratically elected peace committee play a role in preventing violence, loss of possessions to maintain resources (Eriksen & O´Brien, 2007).

4.9 Partnerships in practicing adaptation and mitigation for poor rural people A broad range of emergent adaptation policy development evidences the rapid development of adaptation measures and strategies to address climate variability. At international level, different adaptation finance mechanisms established by UNFCCC and the Kyoto Protocol, more specifically including Global Environment Trust Fund, Special Climate Change Fund, Least Developed Countries Fund, and Adaptation Fund; the first institutional adaptation plan has emerged rapidly from developed nations over the past six years, particularly at the state or province and local government or municipal scale (Preston et al., 2010).

Challenge of climate change requires coordinated action and united support of the international community as a whole. International organizations such as, IFAD, FAO, WFP and other development agencies can bring their collective resource with their knowledge to support poor smallholder farmers. For instance, they have an experience of working at field level with rural poor people on natural resource management and flood control, soil and water conservation, water-harvesting technologies and other projects in different part of the world, especially in arid and semi-arid regions, based on the principle of common, but differentiated responsibility. IFAD at local and national level have experience to respond to climate change challenges through building capacities, by designing climate proof investments and mobilized resources. FAO works in agriculture in general, and in forestry sector, they are technically a good source of global information related to coping with climate change and extreme events. WFP, try to solve food insecurity by providing support during conflict and causes of climate related disasters, and private sectors are also the major source of funds for adaptation and mitigation (Rahman, 2008).

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5. Practicing Adaptation, Key Points and Questions to be answered

5.1. How can preferable technical solutions for climate change being applicable by societies? There are so many questions, which still not got answers. The magnitude and rate of climate change events throughout the world on various natural disasters are ongoing processes causing loss of biodiversity and loss of life. Since the effects of climate change are more serious in developing country when compared to developed country, it can be good to focus in questioning around developing world. Weather events of climate change have different impacts in different part of the world, since the occasions are also differ according to the locality and regions. For instance, in some areas drought frequently caused by low amount of precipitation, then it affects plant growth, the living habitat and ecosystem in general, in other region high precipitation and flooding caused a disaster in human life, habitat and plantation.

As far as it has been assessed and problems identified frequently affecting specific regions, we need to plan and practice different adaptation measures accordingly. An example of such is by asking how people tolerate the changing conditions; especially those most affected in a society and dependent of agricultural farming activities. For regions, which mostly are affected by drought we have to prepare improved drought resistance varieties and properly work until it reaches to the rural poor society. Planning on water harvesting techniques and other options, which can be applicable by individuals (Table 3 & Table 5). The plan should also focus on poor families’ wellbeing to improve capacity of adapting the climate change, by diversification. However, the question is, do we have a capacity to produce an improved variety in high rate as the quality and quantity we need? in practice the answer is no, because it is difficult to satisfy the need of progressed in demanding and using improved varieties, since we have specific and limited capacity, technology, equipment, capital, knowledge, and professionals etc. In addition, the cost of this improved products are high, because it is the result of long process of many years breeding techniques, that makes it expensive, so this area needs the participation of individual investors, corporations, nongovernmental organization, etc. There should be an integrated organized and planned way of solving problems in short or long term, for example working on capacity building of the poor society. It is the most important part in practicing adaptation measures, otherwise for poor society; they have nothing to do except accepting the hazard. Thus, in problem solving and in practicing adaptation option it is crucial to make ongoing evaluation every time, to see whether the strategy works in practice or not.

How people themselves solve the problem? Traditional methods should be encouraged and organized, (by making some scientific modification spreading back to society) can help the societies, because, it can be easier to practice and may not require long time as new innovations (new technologies) to be acceptable by the society. Hence, our technologies

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sometimes require very sophisticated equipment with high capital and labor power etc. Moreover, focusing in sharing experience from similar communities who are practicing better adaptation mechanisms might be also a good approach to be acceptable by the society in developing world. According to Adger et al (2007), Even if we need to transfer technologies to developing countries there are some potential limits as an adaptation response to climate change, farmers prefer according to their capacity they might choose traditional modified technologies and are mostly succeed for mitigation and adaptation in poor society. One of the limits and barriers in adaptation of practicing the measures is cost effectiveness for actual implement. For example, in soil conservation strategy, farmers prefer the cheapest and less time and labour consuming practices. e.g. planting grass strips, hedge row plants, mixed cropping, etc. rather than digging terracing or constructing cut off drain to convert or slow down the downward collected water movement (as runoff) to protect plantation and farm land from soil erosion, stone bund or check dam construction and some adaptation options may not be acceptable socially or culturally.

Depending on their capacity, worldviews, values, believes and many other factors individuals, community etc., may have different risk tolerance and preferences about adaptation measures. Therefore, we need to increase and proceed with giving attention to increase the capacity of practicing potential adaptation options especially of the poor countries, regions, community and social groups in order to approve sustainable development. In one hand, the capacity of poor people is very limited in challenging the hazard. They are unable to use inputs, improved varieties and other mechanism to save their families from famine and hunger. Due to less capacity, the problem become higher in developing countries, since the occurrence of change in climate happening repeatedly, moreover, the agricultural system is local with traditional equipment, which is highly dependent on rainfall, there is no wide intensive farming activities and the society do not have deposited or stored crop products for consumption. Population growth, area of cultivated agricultural land and productivity are proportionally not balanced. This is also one of the reasons to the poor society becoming highly vulnerable to climate change, and the problem facilitated by in proper land use and deforestation.

5.2 What will happen to poor community in high vulnerable developing countries because of less adaptation options? The reduction of yield from crop production in some part of the world, which occurres year after year and not only because of nutrient availability but also due to variable climate, the effect of drought can cause losses of some assets of the poor communities.

Below Figures 9 a, b and c, show effects of climate change variables, in the wellbeing of the poor society in developing countries. http://www.wri.org/publication/enabling-adaptation-climate-change [accessed 04 Feb. 2011].

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Figure 9(a) Effects of drought on a poor society.

As the effects of drought increase through time, most of poor society and farmers in developing countries become unable to resist the impacts of climate change. Farmers do not get information about the current and future climate condition; therefore, they have few adaptation options. As consequence, they will suffer, and forced to stop their kids from school. They start to sell some of their farm tolls, equipment, livestock, and other important assets; as a result, they make different change on their way of life and they are not able to improve or return to their previous living condition, their wellbeing become declined Figure 9(a).

Figure 9(b) Resilience of farmers by using options of adaptation.

The other option of adaptation is working with organizations, by providing different programs and technical support to the poor society. Even if drought affects the wellbeing of the society to a certain level, we can see resilience of the poor society. E.g. by using different safety net programs, insurance services, using stored food from government, or non-government

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organizations, etc., and by using some options of adaptation measures they try to return quickly to their previous wellbeing situation Figure 9(b).

We also have another option in which adaptation practices used properly to save the wellbeing of the society Fig. 9(c).

Figure 9(C) Adapting the drought after using adaptation options through time.

Farmers and poor society in developing world, those who have a chance of getting adequate information about the coming disasters or early warning information, they can in advance prepare for it, they might have an experience how to adapt the coming climate change or drought. For example, by saving and storing food crops for consumption to use during occurrence of shortage, collecting and saving water to use during drought condition, using drought resistance crop variety, using early mature crops, irrigation etc., in which the options can differ according to the locality. That means in some way they try to save and maintain their family well-being without declining, stay by adapting the changing condition Fig. 9(C).

5.3 Criteria for good adaptation practice Adaptation measures at national scale, regional or local level, the policy as well as requirements can vary from country to country, and good adaptation might need to have the following key elements

- The climate adaptation strategy should link (correlated) with day-to-day economic activities. E.g. Agricultural development policy and practices of different sectors, forestry and water management…etc.

- The action of adaptation needs to be done at multiple levels such us in national, regional, state and local (up to small projects and individual household level).

- The action needs to be from top to down, the top policy change should focus on approving behavioural change of the poor individual families and the community. For

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instance, agricultural extension service should provide information about climate change to the rural farmers and giving technical advice and support by forming an approach from top government down to the spot on field of production level.

- There should be participation of local communities during planning, implementing and giving priority of feedback information from bottom and upwards about the innovations of adaptation successes to make them suitable for national decisions.

- People, especially those most vulnerable to climate change, must be involved in any of adaptation processes and all steps, starting from planning up to decision making at any level. In addition, their right should be considered in global and national governments.

Since the changing climate is not entirely in our hands, we are not exactly sure about what will happen. Thus, it is important that our adaptation measures need to be flexible, easy and ready to adjust to be adaptive. For example giving high attention for natural resources on which majority of people depend, such as an ecosystem services like water for drinking and soil for crop production (http://www.wri.org/stories/2009/03/adaptation-key-questions-and-answers) [accessed 04 Feb. 2011].

5.4 What kinds of adaptation measures for climate change are successful in forestry? Climate change influences forest; including soil properties, tree growth, and disturbance regimes, rang shifts, the occurrence of diseases and insect dynamics. Change in tree growth may be determined by how much the climate warms. Hence, higher temperature increases may lead to growth reductions, but the plant growth may also be affected by changes in tropospheric ozone concentrations, deposition of nitrogen, elevated CO2 levels, and land use changes that has a combined positive or negative effect on forest growth (Evans & Perschel, 2009).

We have several options for forest management practices as adaptation to climate. Options for adaptation vary according to geographical regions and forest type, etc., beyond that, adaptation in commercial forest operations are very different from those practiced by communities in developing countries that depend on forest for subsistence (Seppälä et al., eds., 2009).

We have to encourage people who are investing their capital and resources in researching for growth rate improvement in breeding of quality tree variety (disease and drought resistance). In addition, governments should consider and give attention in planning for a better policy that encourage investors and providing necessary information for technical or material support, advice and follow up, since the results of this work may take long time to achieve.

Forest and forest communities face significant impacts of climate change. Sustainable forest management already based on different potential measures to adapt climate change presented

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following the references section. Planned adaptation can reduce vulnerability for commercial tree species at some selected sites; however many forest species will have to adapt autonomously and the forest community needs to adjust to the results. To be successful in adaptation we need to have sustainable forest management plans, and consider different options as part of the risk management, so that we are able to use suitable options wherever needed (Spittlehouse & Stewart, 2003).

Actions, which are able to conserve and restore biodiversity, are a good means of enhancing the resilience of ecosystem to climate change, weather events and other stress factors. In many situations, practicing an adaptation measures to climate variability and mitigate greenhouse gas emissions especially in forest sector are compatible with efforts to tackle the associated threats of habitat distraction, fragmentation and degradation (Seppälä et al., eds., 2009).

5.5.1 Locally practiced traditional adaptation actions in forestry Traditionally forest management practiced by the local community for the purpose of collecting and using medicinal plants from forest covered areas, to grow shade loving species and some stimulant crops under forest tree. Culturally in few areas, forest cut is forbidden since they use for beekeeping, recreation, shade for livestock, small scale use of trees and branches for construction and fuel wood, etc. Furthermore, integrated local forest management in developing countries include planting of fruit trees, which are edible and can used as a source of food nutrition and a source of income for the local communities. Thus, replanting of indigenous plant varieties is important.

Local knowledge and associated forest management practices have sustained, indigenous communities throughout the world under changing environmental, social, and economic condition long before the coming of formal forest science and scientific forest management. Traditional land use practices, decision making a strong correlation and beliefs between the community and the forest environment. The negative implication of loss of livelihood, cultural and biological diversity and the capacity of forested landscape to provide ecosystem goods and services remain poorly understood, largely unappreciated and undervalued by policy makers and the general public in most part of the world (Seppälä et al., eds., 2009).

To some degree, climate change increases the frequency and severity of some disturbance, for e.g. area that are susceptible and affected by wind blow from windstorms can be mapped and vulnerable stands can be managed for species more resistance to wind throw. Species specific for insect infestation or out breaks, tree stands managed to reduce the dominance of preferred species, thinning practice, to local disturbance, such as wind or drought, to make the tree better resistance. In some cases, the most appropriate reaction to disturbance is to allow nature to take its course; however, in other cases societal concerns may dictate some sort of response such as salvage logging or replanting. Forest preservation in reserves plays an important role in

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preparing for climate change as well as storing carbon, old growth reserves store larger amounts of carbon than young forests and genetic diversity will help species adapt to climate change (Evance & Perschel, 2009).

5.5.2 Common barriers in adaptation In different phases of adaptation, we expect barriers. In first phase, accessibility of information (willingness and ability to use information) can be a factor. Agreements, clarity of authority and responsibility over selected options in planning stage, availability of technologies, and needed experts, availability of data and evaluation methodology, willingness to learn, to revisit previous decisions, and ability to store, organize, analyze, and retrieve data in managing and evaluation stages (Moster & Ekstrom, 2010). In addition, political, cultural, institutional, capital, ecological and other factors can affect practices of adaptation.

The response of the forestry sector to extreme climate events and longer-term changes in climate patterns has been reactive in most cases. The effects and adaptation decisions become more divers and complex as we move from smaller to larger scales with an increase in the number of stakeholders. Adaptation strategy must clearly deal with uncertainty during projections of future climate change and their impacts. In some cases because of uncertainty over future policy development, there is a feeling on forest owners that they are not able to manage their forest operation in the future, thus no incentive to plan for adapting to uncertain climate changes (Seppälä et al., eds., 2009).

It is Important to understand the socio-economic, biophysical and operational barriers to adaptation in forest industry. For instance, community based conflict about water use rights and fire management needs legal framework, which supports and promotes adaptation (Pinkard et al., 2010). According to Keithley & Bleier, (2008), constraints in implementing adaptation plan and measures includes

- A limited understanding of the climate risks and vulnerability in the forest sector - Contrast and divided views of environmental effects of forest management. - Limit capacity and capital to implement proposed actions, etc.

Adaptive management involves simultaneous implementation of alternative treatments, such as adaptation measures and policies in different localities, comparing and evaluating the result to test hypothesis about the behaviour of complex systems. The ability for climate change in causing a change in system´s response to treatments might be an important consideration in future applications of adaptive management in the forestry section, for instance the forest theory and practices in the current forest biodiversity conservation and management often should focus on reducing the human influence on forest reserves. In regions where there is rapid change in climate, we might need an active management strategy to conserve very

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important elements of biodiversity. In addition, adaptation measures need an estimate of cost benefit analysis, but in practice currently, most measures do not fulfil such analysis and estimates. In general, current conditions and near-term choices about development and adaptation will have consequences and influences on future adaptation options (Seppälä et al., 2009).

6. Techniques of Mitigation in Agriculture and Forestry According to Adger et al. (2007), agriculture contributes to about 50 and 60 percent of global emissions of methane and nitrous oxide, respectively (mostly nitrous oxide from fertilized soil and methane from livestock).The total contribution of GHGs from agriculture is estimated 10 to 12 percent of the total anthropogenic sources. If emission from deforestation, land use change and indirect emission from fertilizer industries added, the total contribution will rise to 26-35 percent, and 80 percent of these agricultural emissions come from developing countries. Mitigation in agriculture refers to reducing GHG emissions and increasing the sinks for the gases already emitted includes: (a) Reducing emissions of CH4, CO2 and nitrous oxide through efficient control and management of agricultural practices; (b) Enhancing removals of CO2, carbon storage and carbon recovery through improved management of agro ecosystems, and promoting agro forestry (e.g. planting of perennials in agricultural fields); (c) Avoiding emissions, agricultural crop residues used as a source of fuel, directly or after converting to fuels such as ethanol or diesel (Rahman, 2008).

There are a lot of factors affecting forest ecosystem following climate change, which can act independently, or in combination, forests are particularly sensitive to climate change, because the long life span of trees does not allow for rapid adaptation to environmental changes (Lindner et al., 2010). However, trees when compared to other plant species, are uniquely qualified to withstand directional environmental changes, because their longevity with phenotypic plasticity allow to survive a few decades of adverse environmental conditions (Hamrick, 2004).

Many impacts of climate change, reduced, delayed and avoided by mitigation. For example, in agriculture sector it is possible to increase carbon storage by using different techniques, improving grazing land management, using improved crop, restoration of degraded lands and less productive soils. Beyond that, modifying the production system of rice cultivation, and improving livestock manure decomposition technique to reduce methane gas emission. Reducing N2O emission by using better nitrogen fertilizers application techniques, afforestation, reforestation, forest management and emission reduction by reducing deforestation (ERRD). Improving the harvested wood product management and using forest products for bio-energy to replace fossil fuel use. Minimizing improper utilization of resources and avoiding improper

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land use techniques, like protection of natural habitat and forests, and practicing soil and water conservation structures, can be implemented in socially and economically sustainable manner. Forestation and bio-energy plantations can lead to restoration of degraded lands, managing water runoff, retain soil carbon and benefit the rural economies; however, if these activities are not properly designed, the way in which we utilize the resources, e.g. our land use for food production etc., can cause an impact on biodiversity (IPCC, 2007).

7. Discussion Following climate change and climate variability in different studies and by referring some related literature, I suggest two important effects of warming and elevated CO2 on especially valid for agricultural ecosystems: 1) Plants and in already warm areas will become less productive and the production of plants in cold areas may increase when exposed to higher temperature. 2) Increased CO2 concentration may have a positive effect on plant growth.

Higher temperature can make an obstacle on crop growth, the rise in temperature shorten the growth period due to early flowering and fruit-bearing, and seeds might not fully develop because of decrease in nourishment sent to the seed due to increased respiration. In addition, elevated temperatures at the flowering stage of some plants (e.g. rice) makes the plant spikelet sterile. In the case of Japanese rice, the anther will have difficulties to tear when the air temperature is over 34oC, thus global warming should in some areas be consider as a threat for food security (Furuya, & Kobayashi, 2010).

However, higher temperature can directly stimulate root and microbial metabolic activities and respiration that indirectly can have an impact on soil respiration through making a change in plant growth, because of enhanced CO2 level and warming stimulate export of carbohydrates to the roots (Wan et al., 2007). Lukac et al., (2010) also mention that, increasing temperature will speed up the release of nutrients locked up in the mineral soil fractions and thus potentially stimulate growth, however decreasing soil moisture that may be a result of higher temperatures may limit this process.

Currently it is not well know which the net effect of increasing temperatures are as many processes are involved and some will be affected positively and some negatively, e.g. photosynthetic rate, respiration, photorespiration and volatile organic compound (VOC) production. Although, it is quite clear that an increased temperature in some hot area can cause a reduced photosynthetic rate due to overheating effect closure of stomata during drought stress. These all together may reduce the general growth and development of the plants (Prieto et al., 2009) in particularly in warm areas.

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Research suggests that for some crops, such as rice, the benefit of CO2 may decline quickly as temperature warm beyond optimum photosynthetic levels, however crop plant growth may benefit relatively more from CO2 enrichment in drought conditions than in wet conditions (Easterling, & Apps, 2005). Warming also allows the pole ward spread of exotics and pathogens such as malaria transmitting mosquitoes and pests of main food crops such as corn-boring insects, and can increase regional water loss, that directly affect productivity and human survival ( Chapin et al., 2000).

Increasing the concentration of CO2 leads to normally to positive impacts on crop growth (Furuya & Kobayashi, 2010). According to Hardy, (2003) this suggestion is partly supported by the following statement: enhanced CO2 in general shows an increasing photosynthetic rate in individual plant; nevertheless, this increased productivity does not necessarily benefit plants, in the condition where several kinds of species grown together, due to increased competition, availability of nutrient diminish. Any benefit of enhanced atmospheric CO2 and overall, the effects of [CO2] enhanced atmosphere on community of vegetation are complex and not well understood.

Study by Wan et al. (2007) shows that an elevated CO2 concentration can stimulate not only plant growth, but also stimulate the allocation and availability of carbon substrate supply at the ground below soil level as an input of substrate for different soil microbial activities and plant root system. Therefore, it might be possible that enhanced [CO2] rise, air warming and variation of precipitation will likely have an interactive and complex effect on plant soil process.

Increased CO2 content in the atmosphere is expected to increase the yield of many agricultural crops by 5 to 15%; however, CO2 fertilization in climate impact model is an uncertain factor (Roos et al., 2010). Study by Uprety et al., (2010), shows that due to elevated CO2 concentration the increased in the yield was based on the improvement in the development of the number of grain (more ears per M2) rather than heavier kernels. Moreover, elevated CO2 under high nitrogen availability brought about higher starch content in wheat grain due to an increased in carbohydrate translocation from the source (leaf, and steam) to sink (grain). Elevated CO2 alters litter quality, with significant decreases in its nutrient content, which means less nutrients per unit mass, coupled with slower litter deposition under elevated CO2; therefore, nutrient availability may be reduced in the long-run and thus counteracting the positive effects of increased CO2 concentrations, at least in nutrient poor systems (Lukac et al., 2010).

Furthermore, land use change will have an impact on climate change; for instance, if we take grazing of livestock, (in most cases, land without crop cultivation exposed for grazing). Under none controlled over grazing there will be a loss in biodiversity in forest ecosystems. Thus, soil exposed to erosion, reduction in major soil nutrients, gradual decline in fertility of forest soil, slow regeneration of plant species, compaction of top soil, further which leads to an increase in

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bulk densities, decreases infiltration rates, formation of hydromorphic humus, increases surface runoff, tree root damage which facilitate root rot. In addition, the total forest area boundary shrinkage, removal of the biomass and a dominance of single or few species and alters forest dynamic loss of habitats for forest and shade dwelling species (Afreen et al., 2010). May be due to destruction of forests and grasslands, almost 20% of worldwide CO2 emissions are released (Ulukan, 2008). In a place where deforestation is highly affecting the diversity of flora and fauna, afforestation or reforestation/ new plantation of different suitable species, converting non-forest land to forestland will be one of the solutions for better forest ecosystem. We can increase environmental benefits, by reducing erosion and protecting water shade, increasing carbon stock, and controlling salinization, etc. (Afreen et al., 2010).

There is a Prediction of global mean temperature increment in between 1.8oC to 4.0oC by the year 2100. In such warming, a wide range of impacts on terrestrial ecosystems and their diversity will be affected. Furthermore, the effect will be higher on different sectors such as agriculture, forestry, and health…etc. and natural disasters expected to increase following rise in temperature (Mimura, 2010).

There are two basic counter measures regarding climate change, mitigation and adaptation (Mimura, 2010). Mitigation includes different measures, undertaken to reduce GHGs emission and increasing absorption of GHGs, which already emitted, and adaptation indicates different potential measures to protect the adverse effects of climate change.

According to IPCC (2007), all societies have inherent abilities to deal with certain variations in climate, yet adaptive capacities are unevenly distributed, both across countries and within the societies. Adaptation of agricultural and forest system is very complex, because of external and internal factors , e.g. temperature, humidity, light, water availability, photosynthesis, and especially genotypic factors, as discussed above will play a major role (Ulukan, 2008). According to (Mimura, 2010) Impact of climate change determined by the following main factors,

- Climate stimuli:-the degree of the external forces - Susceptibility: - the weakness of an exposed systems to a particular influences - Resilience: - The ability of the system to resist damage

These factors may be summarised in the term vulnerability which is a balance between factors causing damage and the system ability to handle them, and it can expressed by the ratio of external forces to the resilience minus the susceptibility. That means vulnerability increase with an increase in different external forces, susceptibility and decrease with resilience. As the incidence of external forces (extreme events, sea level rise etc) become constant, increasing resilience or adaptability will result in reduced vulnerability. When we refer to sustainable

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adaptation measures, as mentioned by Eriksen & O’Brien (2007) we might need to focus on the following measures:-

- That target the risk posed by climate change to the poor, for instance deterioration of water and destruction of social infrastructure and the viability of cropping systems and other source of livelihoods.

- Those measures that targeted to make strengthen the capacity to cope with and adapt to climate stress, for example involving in alternative source of income during drought, accessing forest products, or seasonal movements of livestock for grazing and so on.

- Those measures that address the cause of vulnerability, for instance, conflict, poor social and physical infrastructure, poor market relations in a particular product, etc.

Climate change adaptation and mitigation are closely linked and complimentary. The importance of forest to climate, successful mitigation requires that forest are able to adapt climate change and reduction emission from deforestation and fossil fuels are required to preserve adaptive capacity of forests and enable them to continue in making their vital contribution to mitigation of climate change (Seppälä et al. eds., 2009).

8. Conclusion Industrialization and unmanaged utilization of resources results in higher rate of GHG emissions and accumulations in the atmosphere, which might result in effects many years later. In addition, population growth, urbanization and industrialization will result in a higher demand of renewable and non-renewable natural resources. Even though, currently there is a gap between availability (supply) and demand of increased population interests, there is a need to consider a more careful utilization of natural resources. Activities of filling the gap must be by reducing emission and protecting the coming generation, and make them beneficial.

To tackle problems associated to climate change we have to focus on practicing activities of mitigation and potential adaptation measures. To protect the environment, mitigations should be proactive by preventing and minimizing emission from source before they are emitted to the atmosphere or by activities of conservation and substitution of energy, carbon sink, and using modern technologies etc. Through adaptation measures, we can protect marketable and non- marketable ecosystem services from damage and our actions have to be ongoing and flexible. Identifying uncertainties in climate change can help us to reduce the challenges in performing adaptation practices and trying to protect and resist risks of climate events.

Our adaptation practices need technologies and suitable policy options as main tools, thus, preparation of guidelines and technology options has to be, socially acceptable, environmentally sustainable and effectively applied. Moreover, forming continuous awareness

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about climate change and adaptation issue might help to make the communities more participatory in all processes of adaptation (from planning, decision-making, implementation to evaluation steps).

As climate change have contrasting effect in different part of the world, it mainly affect the developing world, causing variability in precipitation, solar radiation, temperature,[CO2] humidity etc, it leads to increased infestation of disease, insect, pest and dispersal of weed, which may affect food production and productivity. When the ambient factors affecting growth will become beyond the tolerance of the plant species, it will have a negative effect on their reproduction, life cycle and eventually extinct of the species from natural ecosystem.

There has to be great consideration of increasing environmental benefits from forest ecosystem by afforestation, reforestation, for carbon sequestration, and storage of carbon as a biomass. Moreover, forest ecosystem can serve as a home or habitat for living organisms.

Finally, it is crucial to use different effective conservation strategies to maintain species, genetic diversity, and ecosystem services, and to proceed with research on different plant species to investigate their response to climate variability, and to identify which species will be most restricted in range and which will be most endangered and how they can be protected from extinction.

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