Comparison between conventional land evaluation and a ... · management at intermediate to high levels and thus achieve high crop yields. By considering the strengths of both methods,

Comparison between conventional land evaluation and a method based on farmers’ indigenous knowledge

Case study in Lom Sak District, Phetchabun Province, Thailand

Pattaraporn Sojayya March, 2005

by

Pattaraporn Sojayya

Thesis submitted to the International Institute for Geo-information Science and Earth Observation in partial fulfilment of the requirements for the degree of Master of Science in Geo-information Science and Earth Observation, Specialisation: (fill in the name of the specialisation) Thesis Assessment Board Prof. Dr. Ir. K. (Karl) Harmsen (Chairman) Prof. Paul Driessen (External Examiner) Dr. Ing. W. H. (Erik) de Man (Internal Examiner) Dr. Ir. C. A. J. M. (Kees) de Bie (Main Supervisor) Dr. A. (Abbas) Farshad (Co- supervisor)

INTERNATIONAL INSTITUTE FOR GEO-INFORMATION SCIENCE AND EARTH OBSERVATION

ENSCHEDE, THE NETHERLANDS

Comparison between conventional land evaluation and a method based on farmers’ indigenous knowledge

Case study in Lom Sak District, Phetchabun Province, Thailand

Disclaimer This document describes work undertaken as part of a programme of study at the International Institute for Geo-information Science and Earth Observation. All views and opinions expressed therein remain the sole responsibility of the author, and do not necessarily represent those of the institute.

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Abstract

Land evaluation (LE) supports the process of land use planning. Conventional land evaluation

has been carried out unsatisfactorily for three decades. Land users and planners are reported to

ignore land evaluation results, because of its poor quality, low relevance, or poor readability. LE

in Thailand also suffers from this. To explore the strengths and weaknesses of LE at LDD, this

study tries to compare it with a LE method based on farmers’ indigenous knowledge. It aims to

integrate the relative merits and strengths of both methods to improve the LDD LE method.

Individual farmers of 53 selected fields in Lom Sak district, Phetchabun, North Thailand were

interviewed using an open-end questionnaire. Results revealed that the farmers have a relatively

good knowledge of their land in terms of soil quality, potential and limitations for crop

production. The farmers assess their land suitability by taking both biophysical factors and socio-

economic factors into account; they rate more weight on the latter factor. The most important

factor on biophysical aspect is water requirement during the growing period whereas profit per

land unit is being considered as the most important socio-economic aspect. On the contrary, LDD

land suitability classifications were rated by biophysical factors only taking into account the most

limiting factor as final determinant. Land suitabilities for both methods were compared to land

ratings based on crop yields of actual land use. It was found that the land ratings overestimate LE-

suitabilities because, in reality, farmers apply inputs especially fertilizer, technologies and

management at intermediate to high levels and thus achieve high crop yields. By considering the

strengths of both methods, a striking conclusion is that bringing together conventional knowledge

and farmers’ indigenous knowledge may provide an effective LE which addresses the needs and

objectives of the land user and the community.

Key words: Land evaluation; land suitability classification; farmers’ indigenous knowledge.

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Acknowledgements

I have realized that this study cannot be completed with a single individual endeavor. I would like to thank all who have contributed to the completion of this research. My gratitude of his valuable advice and guidance goes to my first supervisor, Dr. Kees de Bie. I am so grateful to Dr. Abbas Farshad, my second supervisor, for his supports and advice. I am thankful to Dr. Dhruba Shresta, my field supervisor, for his contribution and I would like to thank his family for very warm welcome during my stay in the Netherlands. I would like to thank the LDD for giving me an opportunity to further study and granting the financial support for the study. I am thankful to Mrs. Parida Kuneepong for her supports involving her coordination roles in the projects of the LDD and ITC. During the fieldwork, I really appreciate the help in providing relevant data of my colleagues in the LDD, Mr.Anukul Suchinai, Mr.Paitoon Kadeethum, Mr. Bunrak Patanakanok, Pim, and Vaw. I am deeply thankful to Poo for his assistance and becoming a car driver during my field study. My special thanks are also extended to the Thai farmers. I really appreciate their willing in devoting their times and their knowledge, which are valuable for my research. I would like to convey my special thanks to Kannika Sahakaro and Thongchai Meenual for their English editing and again to Kannika for her rectifying this entire study output. I also deeply appreciate the valuable supports and encouragement of my Thai friends in Enschede, Pawalai, Prat, Satira, and Chaichoke. You all have made my life in the Netherlands pleasant and memorable. My thanks are also extended to Ngo Van Tu for his kind help and constant support toward everything I had asked for and to other ITC classmates, Ha, Blanca, Yadav, Daniel, Benjamin, and Kilangi for creating a cheerful studying environment and their friendship. I also would like to thank all ITC staff for their professional services and supports. Finally, very special thanks to my beloved family for their love, care, encouragement, all supports. I am grateful for their continuous love and understanding.

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Table of contents

1. INTRODUCTION..........................................................................................................................1

1.1. BACKGROUND .........................................................................................................................1 1.2. RESEARCH PROBLEM...............................................................................................................1 1.3. RESEARCH OBJECTIVES ...........................................................................................................3 1.4. RESEARCH QUESTIONS ............................................................................................................3

2. LITERATURE REVIEW..............................................................................................................4

2.1. LAND USE SYSTEM (LUS; IN THE CONTEXT OF LAND EVALUATION) ......................................4 2.2. CONVENTIONAL LAND EVALUATION APPROACH ....................................................................4 2.3. FARMERS’ INDIGENOUS KNOWLEDGE .....................................................................................7 2.4. ACTUAL LAND USE ..................................................................................................................7 2.5. APPLYING CROP YIELD DATA TO EVALUATION .......................................................................8

3. STUDY AREA ................................................................................................................................9

3.1. LOCATION ...............................................................................................................................9 3.2. CLIMATE .................................................................................................................................9 3.3. GEOMORPHOLOGY AND SOIL ................................................................................................12 3.4. LAND USE AND LAND COVER ................................................................................................12

4. MATERIALS AND METHODS.................................................................................................13

4.1. MATERIALS ...........................................................................................................................13 4.2. RESEARCH METHODS ............................................................................................................13

4.2.1. Preparation of the sample scheme .................................................................................. 16 4.2.2. Land evaluation based on farmers’ indigenous knowledge ........................................... 18 4.2.3. Yields assessments of actual land uses ........................................................................... 20 4.2.4. LDD Conventional LE..................................................................................................... 21 4.2.5. Comparing the results from both LE methods with land productivity ratings based on crop yields of actual land use ....................................................................................................... 26

5. RESULTS......................................................................................................................................27

5.1. SAMPLING SCHEME AND STRATA MAP ..................................................................................27 5.2. LAND EVALUATION BASED ON FARMERS’ INDIGENOUS KNOWLEDGE ..................................27

5.2.1. Farmers’ soil indigenous knowledge .............................................................................. 28 5.2.2. Farmers’ land evaluation................................................................................................ 31

5.3. LAND PRODUCTIVITY RATINGS BASED ON CROP YIELDS OF ACTUAL LAND USE...................37 5.4. LDD CONVENTIONAL LAND EVALUATION...........................................................................39 5.5. COMPARATIVE RESULTS OF BOTH LE METHODS WITH THE LAND PRODUCTIVITY RATINGS

BASED ON CROP YIELDS OF ACTUAL LAND USE. .................................................................................45 5.5.1. Assessment of LE based on farmers’ indigenous knowledge ......................................... 46 5.5.2. Assessment of LDD LE.................................................................................................... 48

6. DISCUSSIONS .............................................................................................................................50

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7. CONCLUSIONS AND RECOMMENDATIONS .....................................................................53

7.1. CONCLUSIONS .......................................................................................................................53 7.2. RECOMMENDATIONS .............................................................................................................54

REFERENCES .....................................................................................................................................55

APPENDICES ......................................................................................................................................57

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List of figures

Figure �2.1: Land Use Systems (LUS=LU+LUT).................................................................................... 4 Figure �2.2: Schematic representation of activities in land evaluation. ................................................... 5 Figure �3.1: Map of the study area ........................................................................................................... 9 Figure �3.2: Climatic data diagram of the study area (1995-2003)........................................................ 11 Figure �3.3: P-ETo diagram to delineate the growing period................................................................. 11 Figure �4.1: Conceptual framework of the study ................................................................................... 14 Figure �4.2: Research Methodology Flowchart...................................................................................... 15 Figure �4.3: Soil map of the study area .................................................................................................. 16 Figure �4.4: Structured approach to LUT selection (de Bie, 2000) ...................................................... 23 Figure �4.5: Factor rating tables for matching. (de Bie, 2000)............................................................... 26 Figure �5.1: Stratification of study area according to soil type; sample scheme. .................................. 27 Figure �5.2: Factors considered by farmers for assessing land suitability ............................................. 33

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List of tables

Table �2.1: Structure of the suitability classification. .............................................................................. 6 Table �3.1: Climatic Data of Lom Sak District 1995-2003.................................................................... 10 Table �3.2: Crop calendars practiced in the study area (planting to harvesting). .................................. 12 Table �4.1: Land characteristic data ....................................................................................................... 17 Table �4.2: The reference yields............................................................................................................. 21 Table �4.3: Attributes of management for the selected LUTs................................................................ 24 Table �4.4: A list of land use requirements and their determining land characteristics......................... 25 Table �4.5: Soil characteristics used for LDD LE.................................................................................. 25 Table �5.1Farmers soil classification, description and crop limitations................................................. 29 Table �5.2: Soil properties of soil types considered by farmers............................................................. 31 Table �5.3: Farmers’ soil quality rating.................................................................................................. 31 Table �5.4: Factors considered by farmers for assessing land suitability .............................................. 32 Table �5.5: Farmers land suitability ratings............................................................................................ 37 Table �5.6: Farmers’ crop yield data ...................................................................................................... 38 Table �5.7: Suitability rating classes in term of crop yields ................................................................... 38 Table �5.8: Land productivity ratings based on crop yields of actual land use ..................................... 39 Table �5.9: The suitability ratings for individual crops.......................................................................... 40 Table �5.10: LDD land suitability ratings............................................................................................... 43 Table �5.11 : Comparison between the factors considered by farmers and the diagnostic factors used

by LDD for assessing land suitability. ......................................................................................... 44 Table �5.12: Comparison between the farmers’ land suitability ratings and the land productivity ratings

...................................................................................................................................................... 46 Table �5.13: Comparison between the LDD’ land suitability ratings and the land productivity ratings49

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List of appendices

Appendix 1: Field data capture form .................................................................................................... 57 Appendix 2: Land use requirements for the selected land utilization types ......................................... 62 Appendix 3: Codebook for the terms and keys used in the study ........................................................ 68 Appendix 4: General key informant data.............................................................................................. 70 Appendix 5: Farmers soil classification................................................................................................ 71 Appendix 6: Land suitability assessment by farmers ........................................................................... 73 Appendix 7: Farmers crop yields of actual land use............................................................................. 74

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Abbreviation

FAO Food and Agriculture Organisation of the United Nations FK Farmer indigenous knowledge GIS Geographic information system GPS Global positioning system LC Land characteristic LDD Land Development Department LE Land evaluation LQs Land quality LURs Land use requirement LUS Land use system LUT Land use type, Land utilisation type MOAC Ministry of Agriculture and Cooperatives MU Mapping unit

COMPARISON BETWEEN CONVENTIONAL LAND EVALUATION AND A METHOD BASED ON FARMERS’ INDIGENOUS KNOWLEDGE

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1. Introduction

1.1. Background

Proper land use is a basic requirement for the future of humankind. Pressure on land continuously increases because of population growth. Improper land use results in land degradation. To serve increasing demands, it is necessary to strive for sustainable land use.

Land use planning is a tool to help policy makers, decision makers, and land users, to use land in a way (a) that current land use problems are reduced and (b) that specified, social, economic or environmental goals (e.g. sustainability, food self-sufficiency, income, environmental conservation) are achieved (Omakupt & Huizing, 1992). In land use planning, land evaluation is an important tool to compare or match land use requirements with characteristics of different tracts of land.

The FAO has developed a framework and guidelines for land evaluation (FAO, 1976). Implementation of the FAO land evaluation approach results in fairly unsatisfied outcomes because knowledge used in the evaluation is mainly based on expert knowledge, which comes from professionals through technology transfer. Land evaluation is in practice mainly a physical evaluation due to a lack of qualified natural resource scientists in subjects required for land evaluation (Omakupt & Huizing, 1992). In addition, local knowledge is not included in land evaluation because local knowledge itself is implicit and involves time-consuming and high-cost activities.

In Thailand, land evaluation is the official responsibility of the Land Development Department (LDD) of the Ministry of Agriculture and Cooperatives (MOAC). It has been carried out since the 1960s. Since 1983, LDD had more work related to land evaluation because it has to achieve an additional function: agricultural land use planning. LDD has applied the FAO Land Evaluation Framework in its land evaluation. The FAO-based land evaluation is carried out for its potentials in specific terms of technology, management and socio-economic attributes in order to support current, improved and new land uses (Omakupt & Huizing, 1992). Like in many countries, application of the FAO Land Evaluation Framework has mainly relied on expert knowledge. This research suggests that the LDD land evaluation method can be improved by incorporating indigenous knowledge and local experiences.

1.2. Research problem

One of the most important responsibilities of LDD is to carry out land evaluation and sectoral land use planning (agriculture) for the whole country of Thailand at various levels, e.g. national, regional, provincial, and at district, sub-district, village, and watershed levels.

In the past, LDD generally emphasized land use planning at provincial and watershed levels. LDD also carried out land evaluation as a basis for land use planning. Land evaluation at LDD is based on


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the “frame work for land evaluation” (FAO, 1976) and guidelines on the evaluation of land for rainfed agriculture (FAO, 1983). Land evaluation according to the FAO Framework requires the analysis and integration of different data sets and a close cooperation of natural resource scientists, land use specialists and agro-economist. In practice, LDD LE, like in many other countries, is based on primarily biophysical evaluation because of a lack of qualified staff in all subjects concerned. In addition, data sets used in LDD LE strongly depend on secondary data, especially soil data and defined land utilization types. Soil data are derived from soil maps at 1:50,000. The selection of land utilization types mainly depend on development objectives set by the government for areas concerned. Often crops grown for commercial purpose are evaluated.

The results of LDD LE are land suitability maps for crops and recommendations for use of land units for cultivation, which emphasizes only prevailing biophysical aspect. In recent years, some projects incorporated socio-economic aspects while considering present land uses to produce land use plans at provincial and watershed levels. Omakupt & Huizing (1992) mentioned that the land use plans provide valuable information but that in practice the plans are seldomly implemented, despite the efforts, time and budget spent on them. The fact that land evaluation and land use planning are not an integral part of rural planning and development can be explained by:

• The land use plans are mainly based on a top-down approach, which insufficiently takes into account the aspiration, capabilities and constraints of the local farmers/land users. Without their active participation, any land use plan is likely to fail.

• Land evaluation documents often contain technical language that is not easily understood by rural planners.

• Descriptions of land mapping units and selected land utilization types are often too generalized, i.e. they focus on crops, not land use management.

• Land evaluation relates to technology transfer, which remains unproven to local situations.

In the last 5 years, the Ministry of Agriculture and Cooperatives (MOAC) has focused on developing integrated agricultural development plans at sub-district level for the whole country with farmers’ participation while considering local conditions. Considered information for these plans are land suitability maps generated by LDD. However, such information is normally too general for use for developing integrated agricultural plans at sub-district levels. Infrequently, it wrongly fits to local conditions and farmers preferences. In order to create more user based plans, reviewing land evaluation methods is required. Rojas (2004) also recommended this. Considered here is to improve the LDD LE method by incorporating indigenous knowledge and experiences of farmers. Farmers’ participation in the land evaluation process is explored.

For generations, through observation and experimentation farmers have informally developed knowledge about land qualities and biophysical requirements (Cools et al., 2003). This knowledge is defined as local or indigenous knowledge. Farmers have a comparative advantage to assess land use systems that they are familiar with. Understanding of farmers about their biophysical environment, which is nearly impossible to be captured by land resource experts within a limited time, can be complementary to scientific knowledge. In addition, empirical farmer assessments can be used to verify theoretical scientific estimates of site suitability (Ryder, 2003). Communications between land resource experts and farmers during field visits, proved useful under specific conditions; farmers and


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land resource experts need to support each other (Cools et al., 2003). A research conducted in Thailand shows that such communication is still poor and that transferring of expert knowledge through official channels is still minimal (Huizing et al., 1994). Experts can use the advantages gained by communicating with farmers to develop a better understanding of the local conditions.

The above discussion shows that problems regarding land evaluation might be solved by taking into account preferences and constraints of local land users and by using farmers’ indigenous knowledge. This research aims at studying and comparing the LDD LE method and LE based on farmers’ indigenous knowledge to find out the relative strengths and merits of both methods, so to improve the LDD LE method.

1.3. Research objectives

General objective To compare the LDD land evaluation method with land evaluation based on farmers’ indigenous knowledge, in order to use the relative merits and strengths from both methods to improve the LDD LE method. Specific objectives 1. To study and carry out the LDD land evaluation.

2. To study and capture land evaluation aspects used by farmers’ based on indigenous

knowledge and prevailing conditions.

3. To compare the relative strengths and weaknesses of both methods.

4. To recommend how strengths of both systems can be integrated.

1.4. Research questions

1. Which criteria are used in the LDD LE?

2. Which factors are considered important by farmers to assess land suitability and why?

3. What are weaknesses and strengths of the LDD LE?

4. What are merits of LE using farmers’ indigenous knowledge?

5. How can farmers’ indigenous knowledge be used to improve the LDD LE?


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2. Literature review

2.1. Land use system (LUS; in the context of land evaluation)

According to the FAO (1985), a land use system is defined as a specified land utilization type practised on a given land unit and associated with inputs , outputs, and possibly land improvements. De Bie (2000) also described the system as shown in Figure 2.1. The land use systems (LUSs) compose of two parts, the land Unit (LU) and the land use type (LUT). Essentially, the LU represents the compounded supplying conditions (and limitations) of land whereas the LUT defines a set of land use requirements.

Figure 2.1: Land Use Systems (LUS=LU+LUT)

2.2. Conventional land evaluation approach

Many land evaluation concepts and procedures have been developed. The FAO land evaluation framework is one of the most widely applied in many countries and is still used as a conventional land evaluation method until now. The basic principles of the FAO land evaluation approach (FAO & UNEP, 1999) mentions that: Land resources must satisfy certain requirements if the land is to be used successfully . Many of these requirements are specific to the type of land use, and they include both the ecological requirements of the crop or other biological product, and the requirements of the management system used to produce it. Evaluation of land resources therefore involves a comparison of the properties of the land with the requirements of possible types of land use. Land units are rated according to how well these land-use requirements are satisfied. A conventional land evaluation scheme is shown in Figure 2.2.


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Initial consultations-Objectives-Data and assumptions-Planning of the evaluation

Land mapping unitsKinds of land use

Major kinds of land use orland utilization types

Comparisonof land use with land

-Matching-Economic and socialanalysis-Environmental impact

Land use requirements andlimitations Land qualities

Land suitability classification

Presentation of results

Iteration

Figure 2.2: Schematic representation of activities in land evaluation.

The terms used in land evaluation are defined as follows (FAO, 1976, 1985, 1991, 1995; FAO & UNEP, 1999): Land refer to a delineable area of the earth's terrestrial surface, encompassing all attributes of the biosphere immediately above or below this surface, including those of the near-surface climate the soil and terrain forms, the surface hydrology (including shallow lakes, rivers, marshes, and swamps), the near-surface sedimentary layers and associated groundwater reserve, the plant and animal populations, the human settlement pattern and physical results of past and present human activity (terracing, water storage or drainage structures, roads, buildings, etc.).

Land evaluation is the assessment of land performance or potential with respect to a particular purpose, designed to assist in land use planning and management.

A land utilization type (LUT) is a use of land defined in term of a product, or products, the inputs and operations required to produce these products, and the socio-economic setting in which production is carried out.

Land use requirement or limitation are the conditions of land necessary or desirable for successful and sustained practice of a given land utilization type (cf. crop requirements, management requirements, conservation requirements or limitations).

Land mapping unit is an area of land delineated on a map which may consist either of a single land type or of multiple land types occurring as a complex or association.

Land quality is a complex attribute of land, which acts in a distinct way in its influence on the suitability of land for a specific use.

A land characteristic is an attribute of land that can be measured or estimated, and which can be employed for distinguishing between land units with different suitabilities for use and as a mean of describing land qualities.


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Land suitability assessment: Suitability is a measure of how well the qualities of a land unit match the requirements of a particular form of land use. Suitability is assessed for each relevant use and each land unit identified in the study.

Structure of the land suitability classification Land suitability classification: The suitability classification aims to show the suitability of each land unit for each land use. In the FAO’s Framework for Land Evaluation, land is first classified as suitable (S) or not suitable (N). These suitability classes can then be further sub-divided, as required. In practice, three classes (S1, S2 and S3) are often used to distinguish land that is highly suitable, moderately suitable and marginally suitable for a particular use. Two classes of ‘not suitable’ can usefully distinguish land that is unsuitable for a particular use at present but which might be useable in future (N1), from land that offers no prospect of being used (N2).

Table 2.1: Structure of the suitability classification.

CATEGORY ORDER

CLASS SUBCLASS UNIT

S Suitable

S1 S2 S3 etc.

SS2m S2e S2me etc.

S2e-1 S2e-2 etc.

Phase: Sc Conditionally suitable

Sc2 Sc2m

N Not suitable N1 N2

N1m N1e etc.

Source: FAO (A framework for land evaluation); 1976

The process of land suitability classification is the appraisal and grouping of specific areas of land in terms of their suitabilities for defined uses (FAO, 1983) i.e. the comparison of the land qualities of land mapping units (LMU) with the requirements of a land utilization type (LUT). The result of a separate comparison for each land quality is a number of “partial suitabilities” of the land mapping unit; separate land qualities are combined to come to an overall suitability rating of a LMU for a LUT.

Three methods may be used (de Bie, 2004) for combining land suitabilities and those are (i) subjective combination, (ii) limiting conditions and (iii) parametric methods.

Subjective combination is based on “expert knowledge”. This method will be reliable when the evaluator has a good knowledge of the area and all the LUTs concerned, i.e. if he acquired indigenous knowledge.

The procedure based on limiting conditions is the simplest and most logical one which takes the least favourable assessment as limiting. It applies “the law of the minimum” (Liebig). The suitability will be determined by the most limiting land quality or land characteristic for a particular use.


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In the parametric method, different properties of soils are evaluated separately, and given a separate numerical value according to their importance within and between each other. It is suitable for computerization.

2.3. Farmers’ indigenous knowledge

According to Cools et al. (2003), ‘indigenous’ or ‘local’ or ‘traditional’ or ‘indigenous technical’ knowledge, is the knowledge that people in a given community have developed over time and continue to develop, based on their observation and experimentation for generations. Local people’s insights, perceptions, and management strategies are often attuned to local soil conditions and can offer guidance for realistic land management. Indigenous knowledge of local people is based on experience. It is different from scientific knowledge, which is developed by scientists through controlled experimentation within formal institutions (Winklerprins, 1999). On the other hand, many activities undertaken by rural people and scientists are similar: they distinguish, name and classify entities in their environments, they observe compare and analyze, they experiment and they attempt to predict (Mafalacusser, 1995). Indigenous knowledge is not static but can be seen as a dynamic and ever changing accumulation of the collective experience of generations.

Recently, the study of indigenous knowledge has received more attention by researchers, especially by those involved in sustainable land management. Research on indigenous soil knowledge has recently increased as part of broad efforts to include indigenous knowledge and participatory approaches in sustainable land management projects. Literature describes that local soil knowledge is an important source of information when designing sustainable land management strategies (Barrera-Bassols, 2003; Winklerprins, 1999). Scientists realize that local people possess sophisticated knowledge about soils, and that this knowledge can aid in sustainable land use and in maintaining soil quality (Winklerprins, 1999). In addition, indigenous soil knowledge is an input to land evaluation (Siderius & Mafalacusser, 1998). Bacic (2003) mentioned that it is crucial to know what are the problems, the needs and possibilities of the stakeholders before starting a land evaluation process, otherwise there is a risk that questions may be answered that have no priority or relevance and/or that questions may not be answered properly according to the community expectation.

In addition, Bouma (1999) mentioned that land use and its possible changes are usually more a reflection of socio-economic development in society than the differences in soil suitabilities for different form of land use. Thus, to reach effective results from a land evaluation process, it is crucial to know the important factors and aspects that affect the current and the potential land use alternatives. For this reason, taking into account farmers’ indigenous knowledge is required since farmers are expert on their physical, economic and social environment and they know the goals they are trying to meet, the resources and factors of production they have available and the constraints affecting production (Mafalacusser, 1995). After all, farmers have the final decision regarding what they grow and how they grow it.

2.4. Actual land use

Wishes, preferences and possibilities set by the end users with respect to land uses have been recognized by many researchers (Vargas Rojas, 2004). A use of land is defined in term of a product,


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or products, the inputs and operations required to produce these products, and the socio-economic setting in which production is carried out. Actual land use refers to existing land use carried out by the end users for the particular purposes under their circumstances. In this research, the end users are farmers and land uses refer to their selected crops. Mafalacusser (1995) described that farmers select the crop based on four components i.e. farmer’s objectives, internal factors, external factors and the risk under which the farmer decision is to be made. Farmers know the goals they are trying to meet, and they are also expert on their physical, economic and social environment and their particular farming system. In addition, they are well-informed decision makers, who combine information and techniques to maximize production and minimize risks. Finally, they make decisions on which crop to cultivate.

2.5. Applying crop yield data to evaluation

The FAO (1983) mentions that where reliable data are available, observed crop yields form a better means of suitability assessment than a methods based on land qualities. Crop yield data serve, first as a means of direct assessment of suitabilities for sites where they are available, and second, as a valuable means of checking, and to some extent calibrating, suitability assessments derived from ratings of land qualities. There are two methods for applying yield data to evaluation, direct and indirect. The direct method is simply to plot crop yield data onto the map of land units, or what amounts to the same thing, and draw up tables of observed crop yields recorded on each land unit. Those land units on which high yields are consistently obtained are classed as highly suitable, and so on. For obvious reasons, yield data will be missing from unsuitable land. The indirect method is through deriving regression equations for relationships between crop yields and land qualities. The resulting land suitability classes refer only to the crop components of land utilization types. Rating for management and conservation can not be seperated.


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3. Study area

Figure 3.1: Map of the study area

3.1. Location

The study was carried out in the upper Pa Sak area, Phetchabun province, in the north of the Kingdom of Thailand. It is located in the upper part of the Pa Sak river basin, Lom Sak districts, between 101o 09/ and 101o14/ E and 16o 45/ and 16o50/ N, with an approximate surface area of 50 km2.

3.2. Climate

The climate is tropical humid, influenced by northeastern and southwestern monsoons, with dry, hot and rainy seasons. This is characterised by high humidity, moderately to high temperature and a distinct climate variation between dry and rainy seasons. (Table 3.1 and Figure 3.2)

Precipitation

The mean annual precipitation (1995-2003) is about 101 mm with a mean maximum monthly value of 263 mm in August and a minimum value of about 14 mm in December.


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Temperature

The mean annual air temperature, recorded during 1995-2003, is 27 °C, with a mean monthly maximum of 39 °C in April and a mean minimum of 12 °C in December.

An extreme maximum value of 41°C in April and a minimum value of 6°C in December can be expected.

Evapotranspiration

The mean monthly evaporation recorded is 139 mm, with a mean monthly maximum of 170 mm in April and a mean minimum of 119 mm in September.

Humidity

The mean relative humidity recorded within the same period (1995-2003) is 74 %, with the mean maximum value of 83 % in September and the minimum value of 62 % in February.

Table 3.1: Climatic Data of Lom Sak District 1995-2003

(Lom Sak Meteorological Station Latitude 16°°°°44’ N Longitude 101°°°°14’58”E)

Month Precipitation

(mm) Eto

(mm)

Relative Humidity

(%) Temperature(°C)

Maximum Minimum Mean Jan. 14 127 64 35 12 24 Feb. 22 131 62 37 14 23 Mar. 30 165 64 39 17 28 Apr. 95 170 70 39 22 28 May 156 157 78 38 22 28 June 147 145 80 36 23 28 July 151 137 82 35 22 27 Aug. 263 129 83 35 22 27 Sep. 206 119 83 34 22 27 Oct. 88 132 78 35 20 27 Nov. 19 127 71 35 15 25 Dec. 13 122 66 35 12 24 Total 1209 Average 101 139 74 36 19 27


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0

50

100

150

200

250

300

Jan. Feb. Mar. Apr. May June. July Aug. Sept. Oct. Nov. Dec.

Month

Rai

nfal

l/Eva

pora

tion(

mm

)

0

5

10

15

20

25

30

35

40

45

Tem

pera

ture

(oC

)

rainfall(mm)

Evapo.(mm)

max T(oC)

min T(oC)

rr

rainfall(m

Figure 3.2: Climatic data diagram of the study area (1995-2003)

Growing period

The growing period is the duration of the year when both the temperatures and the soil moisture availability permit crop growth (FAO, 1983). The length of the growing period is 6-7 months when mean monthly precipitation equals or exceeds half mean monthly potential evapotranspiration. The growing period is between mid-April until late-October, after which the dry period starts. During this period cultivation is possible. (Figure3.3).

Figure 3.3: P-ETo diagram to delineate the growing period

0

50

100

150

200

250

300

Jan. Feb. Mar. Apr. May June. July Aug. Sept. Oct. Nov. Dec.

Rai

nfal

l/ET

o (m

m/m

onth

)

Precipitation(mm) Eto(mm) Eto/2(mm)

Humid period Growing period


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3.3. Geomorphology and soil

According to Hansakdi (1998), the present geomorphic configuration of the Pa Sak and Huai Nam Phung rivers area is the result of tectonism, denudation and sedimentation processes. Four major landscapes such as mountains, hill lands, piedmont and valley are distinguished. Piedmont landscape only occurs in the study area. This landscape consists of glacis, swale and vales “relief-types”. The slope gradient of this landscape varies from 2-16 % with gently sloping to undulating. The soils in this area are moderately deep to very deep. The low laying areas are somewhat poorly drained and the upper parts are moderately to well drained. The common texture classes found in the areas are SCL, L, SiL, and SL. The pH range found in the area is strongly acid to moderately alkaline.

3.4. Land use and land cover

Most of the area is used for agricultural and for human settlement. The land is mainly put to rice for staple food during the rainy season, followed by various cash crops such as tobacco, and vegetables during the dry season. In some areas which have enough water, farmers grow a third crop. For area that cannot be put to rice as a first crop, maize is grown followed by a second and sometimes a third crops (Table 3.2).

Table 3.2: Crop calendars practiced in the study area (planting to harvesting).


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4. Materials and methods

4.1. Materials

The following materials were used in the study:

• Geopedologic map of the area at a scale of 1:100,000 • Topographic map of the area (5242IV) at a scale of 1:50,000 • Soil map of the area at a scale of 1:100,000 • Data on land use requirement from LDD and FAO (Ecocrop) • Other materials for fieldwork : GPS, observation sheets , checklist for key informants’

interview and semi-structure questionnaire for farmers’ interview, and a pH test kit • Software used for data processing : ILWIS and Excel

4.2. Research methods

The conceptual framework of the research methodology consists of three modules: (1) LDD conventional LE, (2) land evaluation based on farmers’ indigenous knowledge, this module adopts the basic structure of a land use system and aspects influencing the stakeholder’s decision making as defined by de Bie (2000) for capturing LE aspects used by farmers , and (3) land suitability assessment based on crop yields of actual land use (Figure 4.1). Results of comparison between both LE methods with land suitability assessment based on crop yields of actual land use were used as bases in drawing up conclusions.

The methods followed throughout the study are provided in five sections as under:

1. Preparation of the sample scheme 2. Land evaluation based on farmers’ indigenous knowledge 3. Land suitability assessment based on crop yields of actual land use 4. LDD Conventional LE 5. Comparison of the results from both LE methods with land suitability classifications based on

crop yields of actual land use The research methodology flowchart is shown in Figure 4.2.


14

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15

Figure 4.2: Research Methodology Flowchart


16

4.2.1. Preparation of the sample scheme

Building the research geographic information system

Georeferencing the spatial data source

All the existing maps have been georeferenced to one coordinate system, Projection: UTM, Ellipsoid: WGS84, Zone: 47.

• A topographic map covering the study area was georeferenced. First, the scanned map was imported into ILWIS and nine tie points (at the grid points) were then selected to georeference the map. Affine transformation method was applied to transform the scanned map with a sigma error of 0.16 pixels. This map was used for posterior tasks.

• The geopedologic map, obtained from ITC in scanned format and prepared by a previous MSc. student: Ekkanit Hansakdi (1998),was georeferenced and used for delineating a boundary of the study area .The soil type boundaries were subsequently digitized to prepare a soil map of the study area that includes soil attribute data as reported in the thesis of Hansakdi (1998)and from LDD soil information (Soil Survey and Classification Division, 1988; Soil Survey Division, 1976) generated by a LDD soil surveyor (Figure 4.3 and Table 4.1).This map was used as a basis for sampling and data collection.

A sampling scheme and a strata map for field data collection was designed. In order to select a sample set, stratified random sampling was applied based on the soil map. There were fifty pre-selected sample sites.

Figure 4.3: Soil map of the study area


17

Table 4.1: Land characteristic data

Land characteristics

Pi111

Pi211

Pi311

Pi411

Pi611

Pi613

Pi621

Pi711

Pi811

Geomorphology - Landscape - Relief type - Lithology - Landform - Slope (%)

Piedmont

Hill

Residual

Slope facet complex

8-16

Piedmont

High

Glacis

Residual

Tread-riser complex

2-10

Piedmont

Middle Glacis

Residual

Tread-riser complex

2-4

Piedmont

Low

Glacis

Residual/ Alluvio-colluvium

Tread-riser complex

2-4

Piedmont

Fan

Alluvium

Apical

2-15

Piedmont

Fan

Alluvium

Apical-distal complex

2-15

Piedmont

Fan

Alluvium/ Residual

Dissected apical-distal complex

2-15

Piedmont

Swale

Colluvio- Alluvium

Bottom/ side complex

2-3

Piedmont

Vale

Alluvio-colluvium

Bottom/ side complex

2-3

Rockiness None None None None None None None None None Soil depth (cm) 50-100 50-100 50-100 100-150 50-100 100-150 100-150 >150 >150 Soil texture (class) cl/c cl/gc cl/c sicl/sic sil/gsic1 sil/sic1 sil/sic1 sic1/sic sl/scl pH 7.0-8.0 5.5-6.0 6.0-7.0 6.5-7.5 5.5-6.0 6.0-7.0 7.0-8.0 6.5-7.5 6.0-7.5 Drainage (class) 5 4 3 3 4 4 4 3 3 Nutrient availability (class)

H

M

M

H

M

M

H

H

H

Root penetrate (class)

4 4 4 4 3 3 3 4 2

Workability (class)

2 2 2 2 1 1 1 2 2

Rock out crop (class)

1 1 1 1 1 1 1 1 1

Descriptions of map units

Pi111: slope about 8-16 %, sloping to undulating, well drained and moderately deep soils, texture of top soils are clay loam and clay in sub soils with neutral to moderately alkaline.

Pi211: slope about 2-10 %, Gently sloping to undulating stony surface, moderately well drained and moderately deep soils, texture of top soils are clay loam and gravelly clay in sub soils with strongly acid to moderately acid.

Pi311: slope about 2-4 %, nearly level to undulating, somewhat poorly drained and moderately deep soils, texture of top soils are clay loam and clay in sub soils with moderately acid to neutral.

Pi411: slope about 2-4 %, nearly level, adjoining to river terrace ,somewhat poorly drained and deep soils , texture of top soils are silty clay loam and silty clay in sub soils with slightly acid to slightly alkaline.

Pi611: slope about 2-15 %, nearly level to undulating, moderately well drained and moderately deep soils, texture of top soils are silty loam and gravelly silty clay loam in sub soils with strongly acid to moderately acid.


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Pi613: slope about 2-15 %, nearly level to undulating, moderately well drained and deep soils, texture of top soils are silty loam and silty clay loam in sub soils with moderately acid to neutral.

Pi621: slope about 2-15 %, nearly level to undulating, dissected and incised finger shaped landforms, mixed angular and sub angular gravels, moderately well drained and deep soils, texture of top soils are silty loam and silty clay loam in sub soils with neutral to moderately alkaline.

Pi711: slope about 2-3 %, nearly level, somewhat poorly drained and very deep soils, texture of top soils are silty clay loam and silty clay in sub soils with slightly acid to slightly alkaline.

Pi811: slope about 2-3 %, nearly level, somewhat poorly drained and very deep soils, texture of top soils are sandy loam and sandy clay loam in sub soils with moderately acid to slightly alkaline.

4.2.2. Land evaluation based on farmers’ indigenous knowledge

The main activity of this work was carried out through fieldwork, which was done for a period of 5 weeks (13 September to 18 October 2004). Details are:

Area reconnaissance

The aim was to get familiar with the area and to observe the landscape, land use/ land cover, infrastructure, and socio-economic conditions of farmers. Prepared maps were checked against the reality.

Collecting relevant information from key informants

Relevant information from key informants like agricultural extension officers, leaders of villages, and voluntary staff of LDD, was collected. It gave an overview of local reality. Moreover, it was used for preliminary land utilization type selection and for reviewing the questionnaires. Furthermore, it was used later to verify and check farmers’ responses during interviews.

Capturing farmers’ land evaluation data pertaining to indigenous knowledge

Individual farmers were interviewed on the spot of his land by using informal interview techniques (open-ended questionnaires : see Appendix 1) to capture local soil knowledge, relevant LURs, LQs , soil-crop relationships, and other possible factors or criteria used by farmers for assessing the suitability of land for a specific land use. An interview checklist was used in this study because it is recommended for scientific research in order to prevent overlooking relevant site specific information. It can accommodate a wide variety of information, and it can be tailored to capture all relevant information; it however poses demands on the enumerator and creates difficulties in processing (de Bie, 2000).

In this study, fifty-three farmers were interviewed. The sampled areas consisted of 8 map units (map unit Pi111 was skipped because the land was occupied as a residential area) and the questions used can be summarized as stated below:

a.) (i) What do you call this soil in local terms? (ii) Can you explain the properties of this soil type?

(iii) Is it suitable for cultivation? Why yes? Why no? If yes, please indicate (good, moderate, poor)


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(iv) Do you have any soil problems for cultivating this soil?

b.) (v) Which types of crops/cropping patterns/LUTs are suitable for your field? And why?

(vi) Can you rank them in order or give suitability rating for each LUT? (vii) Why did you rank them or give a suitability rating like that?

For this set of questions, the farmers were let to answer freely by themselves. The results showed that most farmers generally considered their current land use type as the most suitable type for their particular land and hence they did not consider other LUTs. So farmers were requested to give suitability rating for 5 given LUTs as listed below:

• rice • rice + tobacco (edam) • rice + tobacco (edam) + maize • maize + mungbean • sweet tamarind

These LUTs were selected for evaluation as a result of preliminary LUT selection in which it was found that 1) they are dominant LUTs in the area and important to farmers 2) they are relevant to the supposed objectives of land evaluation in this study which aimed to increase the potential of agricultural production for commercial purpose and to maintain the current food crop production levels. More specific, rice is a food crop of the people in this area, tobacco and maize are main cash crops, mungbean is normally grown in combination with maize, and sweet tamarind is a very famous fruit tree in this province.

Locating farmers’ plots on the soil map

Farmers’ plots were located on the soil map by using a GPS. The top soil was tested for pH by using chemical method and the soil texture by the Thien feel method (Thien, 1979). The tests were done by the researcher for comparison with farmers’ soil data and with attributes of the soil map.

Data entering

The data collected in the field were entered in Excel for further analysis as listed below:

• Codebook for the terms and keys used ( Appendix 3) • General key informant data (Appendix 4) • Farmers soil classification (Appendix 5) • Land suitability assessment by farmers (Appendix 6)

Data processing and analysis

The data were processed and analysed. Two sets of categorical data; farmers’ soil quality ratings and the farmers land suitability ratings were assigned values for each class as follows:

3 = good soil / highly suitable 2 = medium soil/ moderately suitable 1 = poor soil/ marginally suitable 0 = not suitable for cultivation/ not suitable


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To come up with a final soil quality rating and farmers’ land suitability class for each LUT in each map unit, assigned values were used to calculate an average value for each map unit. The average value was then converted to a final suitability class according to the assigned range of 4 classes i.e.: 0 to 0.75 = N; 0.75 to 1.5 = S3; 1.5 to 2.25 = S2, and 2.25 to 3 = S1. These ranges are equal distances between values.

4.2.3. Yields assessments of actual land uses

Actual land use is considered as a reference to compare the two sets of land suitability methods. For this reason, yield assessments based on crop performances of actual land uses were needed. Details are: Interviewing farmers about their crop yields obtained through actual land use

The interview results were used for yield assessments for use as a yardstick to compare the result of the LDD LE and the LE based on farmers’ indigenous knowledge. For this part, farmers were asked the following questions:

(i) Which crops do you grow in this field? ( or take a list of crops planted at the moment of interview)

(ii) Why do you grow them? (iii) How much crop yield do you get? And pleases give rating (high, medium, low). (iv) How do you manage your crop to reach that yield?

-crop management -land management

(v) What are the important factors that affect crop yields? And why?

Data entering

The crop yield data collected were entered in MS-Excel as shown in Appendix 7.

Yield data evaluation

Crop yields of the same LUTs were processed by taking their average Then to defined suitability classes in terms of crop yields, definitions provided by the FAO (1983) were used; these are: S1 = 80-100% of a reference yield; S2 = 40-80%; S3 = 20-40%; and N = less than 20%. For the study, reference yields i.e. crop yield data under optimum conditions were taken from research work, mostly from the Department of Agriculture (2004). Tobacco and cauliflower yield data are from other sources (Mae JoeTobacco Experiment Station, 2004; Yimyam, 1986). Because yields data of some vegetables e.g. coriander, chilly, bell pepper, egg plant, and shallot could not be collected from research work, the average crop yields of 2002/2003 obtained from the statistical report of Phetchabun Province, 2004 (Phetchabun Provincial Statistical Office, 2004) were used. The reference yields of all crops are shown in Table 4.2.

For LUTs which consisted of 2 or more than 2 crops, the individual suitability classes of all crops grown were combined; the final suitability class is the lowest rating recorded.


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Table 4.2: The reference yields

Crop Reference yield (kg/Rai)

Rice 660 Tobacco(Edam) 300 Tobacco(Burley) 368 Maize 1050 Mungbean 200 Coriander 2000 Cauliflower 3100 Chilly 1120 Bell Peper 1750 Egg plant 2900 Yard long bean 3300 Shallot 2130 Sweet tamarind 2500

Note: 1 Hectare = 6.25 Rai

4.2.4. LDD Conventional LE

The LDD conventional land evaluation was carried out following the FAO framework.

Crops in the study area

The most important crops in the study area are rice, tobacco, maize and vegetables. Rice is considered as a main food crop and is sold only when the quantity produced is beyond the in-house consumption. Tobacco, maize and vegetables are considered as cash crops. Other crops grown in the area are sweet tamarind and mungbean.

In the study area, two types of rice and two types of tobacco are produced. Rice is classified into ‘normal’ and ‘sticky’ types whereas tobacco consists of ‘edam’ and ‘burley’ varieties. For rice, the two types in terms of crop requirement, yield, and management are similar. On the contrary, for tobacco there are differences between both varieties in terms of yields, management and processing. Burley is grown by contract farmers according to instructions given by the Tobacco stations. In average, ‘burley’ tobacco gives higher yield than ‘edam’. During processing, edam tobacco leaves are sliced into fine strips whereas burley tobacco leaves are dried without slicing. The differences in yields and management justify the formulation of two tobacco land utilization types.

The vegetable referred to in this study is cauliflower. Even though there are many kinds of vegetables grown in the area, cauliflower is the favourite one which provides higher benefit per land unit as compared to the others. Cauliflower is therefore selected as representative vegetable for this land evaluation study.


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Land utilization types

For LDD LE, LUTs are generally selected during the initial stage of the study based on suggestions/ requirements of the organization ordering the study, the policy of the government (Ministry of Agriculture and Cooperatives), and the market demand. Filtering is being applied when new crops are proposed in order to verify whether or not the crops specified can cope with the prevailing climate and soil conditions. Then, secondary data obtained through technology transfer, especially from agricultural research stations, are used. In this study, selected LUTs to evaluate are quite similar with current LUTs.

The selection of LUTs by farmers depends mostly on their experience and indigenous knowledge which is accumulated by trial and error for a long time. According to Mafalacusser (1995),to come up with the crop choice decision, farmers are taking four main components into consideration i.e. 1) the objective of the farmers 2) internal factors e.g. land, water, labour, etc. 3) the external factors which affect their crop productions and 4) the risk related with price variation and the physical environment. For adopting new LUTs, farmers mostly rely on successful advanced farmers. In this area, most of the farmers cultivate the same LUT since many years, mainly because of a lack of information for new LUTs and to avoid taking risk from uncertainty. Hence, when asking farmers to state the suitability crops/LUTs for their lands, most of them specified them only for their current LUTs.

Current LUTs are the result of farmers’ crop choice. Being grown in the area, it is implicit that those LUTs are biophysical and socio-economically suitable, and accepted by farmers.

For this study, the researcher selected current LUTs for carrying out the land evaluation because of the following reasons:

• It agrees with the supposed objectives of land evaluation in this study that aims at increasing the potential of agricultural production for commercial purposes while maintaining the current food crop production.

• It is in agreement with the concept of LUT selection that builds on object-oriented problem analysis, that is through the “use of key attributes for LUT selection queries” as shown in Figure 4.4 (de Bie, 2000).

• It also agrees with LDD and farmers’ considerations.


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Figure 4.4: Structured approach to LUT selection (de Bie, 2000)

Land utilization types considered are: 1. Rainfed wetland rice 2. Sequential cropping patterns: Rice-Tobacco (Edam) 3. Sequential cropping patterns: Rice-Tobacco (Edam)-Vegetables 4. Sequential cropping patterns: Rice-Tobacco (Burley) 5. Sequential cropping patterns: Rice-Tobacco (Burley)-Vegetables 6. Sequential cropping patterns: Rice-Tobacco (Edam)-Maize 7. Tobacco (Burley) 8. Sequential cropping patterns: Tobacco (Edam)-Vegetables 9. Sequential cropping patterns: Maize-Mungbean 10. Sequential cropping patterns: Maize-Vegetable 11. Sequential cropping patterns: Maize-Tobacco (Edam) 12. Sequential cropping patterns: Maize-Tobacco (Edam)-Vegetables 13. Vegetables 14. Sequential cropping patterns: Vegetable-Tobacco (Edam)-Vegetable 15. Sweet tamarind


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Each land utilization type was defined in terms of produce i.e. of the crop or crop rotation and details on how to manage these crops (Sys, 1991). For this study, management levels of all LUTs are at intermediate to high input level. This is based on management attributes described in Table 4.3.

Table 4.3: Attributes of management for the selected LUTs

Attribute Intermediate input level LUT High input level LUT Land holdings Capital intensity Market orientation Labour intensity Power sources Know-how Technology employed

-Small -Intermediate with credit on accessible terms -Subsistence production plus commercial sale of surplus -High, including uncosted family labour -Moderate -Improve cultivars as available. Sub optimum fertilizer application. Simple extension package including some chemical pests and disease control. No conservation measures. Some fallow period.

-Commercial production -Complete mechanization including harvesting -High yielding cultivars including hybrids. Optimum fertilizer application. Weed control.

Selection of land qualities/ requirements and diagnostic factors for LDD LE

There are approximately 25 land qualities which affect suitability for rainfed crops (FAO, 1983). In Thailand, 13 land qualities, considered significant for suitability assessment, were selected based on three conditions: 1) effects upon the use 2) occurrence of critical values within the study area 3) practicability of obtaining information. The appropriate land characteristics to be employed as diagnostic factors for each land quality are summarised in Table 4.4.

In Thailand, all land use requirements and their determining land characteristics are generally relevant. However, in this study some LQs and LCs were not considered because of some circumstances including 1) they have no effect to selected LUTs e.g. radiation regime. 2) no data were available e.g. nutrient retention capacity and excess of salt, and 3) the survey data show that in the area, these factors were not limited for cultivation e.g. water requirement in growing period because farmers could grow the LUTs by using water from canal, farm ponds and artesian wells. Factor rating tables for each crop (Appendix 2) are used for assess by land quality/land use requirement a suitability rating. A list of land use requirements by crop was established from ‘the tables of Crop requirements and factor ratings’ by LDD (1999). Attribute data of soil characteristics used for LDD LE are shown in Table 4.5.


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Table 4.4: A list of land use requirements and their determining land characteristics.

Land qualities/ Land use requirements Land characteristics/Diagnostic factor Radiation regime Day length Temperature regime Mean temperature in growing period Moisture availability Mean annual rainfall, water requirement in growing

period Oxygen availability Soil drainage Nutrient availability Percentage total nitrogen, available phosphorus and

potassium, percentage organic matter, nutrient status Nutrient retention capacity Cation exchange capacity, base saturation Rooting conditions Effective soil depth, root penetration, and presence of

gravel Flood hazard Flooding frequency Excess of salts Electrical conductivity of soil saturation extract Soil toxicities Depth of jarosite, reaction in inundation condition Soil workability Workability class Potential for mechanization Slope, stoniness, rock out crop Erosion hazard Slope, soil loss

Table 4.5: Soil characteristics used for LDD LE

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Matching land use requirements with land qualities

Individual suitability ratings by crop were derived by matching the requirements of each crop (Appendix 2) against the qualities of each map unit. Overall land suitability ratings resulted (Figure 4.5). The final suitability is based on the most limiting factor. In order to come up with the final suitability class for selected LUTs that represent multiple cropping, a suitability class of crops consisting in each LUTs has been combined. In this case, the crop consisting the lowest class is assigned to the LUT. If the suitability class of one crop is S3rwe and another crop is S3r, then the final suitability class for the LUT is assigned S3rwe.


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Figure 4.5: Factor rating tables for matching. (de Bie, 2000).

4.2.5. Comparing the results from both LE methods with land productivity ratings based on crop yields of actual land use

The farmers’ land suitability ratings and the land productivity ratings were compared. Also the LDD land suitability ratings and the land productivity ratings were compared. The results are presented in the form of table.


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5. Results

5.1. Sampling scheme and strata map

There were fifty pre-selected sample sites. However, during fieldwork, some sample sites were adjusted to nearby locations having similar conditions as those of pre-designed sites. Farmers at selected sites were sometimes not available, or it was found that selected sites all presented the same crops / LUTs. This survey needed to observe different LUTs in a map unit. Eventually, fifty three sample points in eight map units were survey and farmers’ interviews were carried out. (Figure 5.1)

Figure 5.1: Stratification of study area according to soil type; sample scheme.

5.2. Land evaluation based on farmers’ indigenous knowledge

As mentioned earlier, the study tried to capture farmers’ indigenous knowledge on land evaluation aspects by interviewing individual farmers using an open-ended or semi-structured questionnaire. Collected information varied but it revealed their knowledge and perception. Collected information from farmers’ interviews was structured in tables for analysis. The results are presented in two parts i.e. 1) farmers’ soil indigenous knowledge and 2) farmers’ land evaluation.


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5.2.1. Farmers’ soil indigenous knowledge

A total of 53 individual farmer interviews were held. The farmers identified 12 soil types. To identify soil, farmers used soil properties to distinguish each soil type and to group similar soils into the same types. Most of the local soil names refer to soil texture and some to soil colour. For this area, farmers mentioned that Din Dam (black soil) is a good soil. It should be noted that there are many soil types that consist of sand texture. The data are quite different than soil data used for LDD LE since this area was affected by severe flooding in 2001 from the upper mountain situated on the left side of the study area (Nam Chun sub-watershed). The flood brought soil (mostly in the form of sand) and sediment onto the top surface of the lowland. This caused a change in soil properties in the area.

Soil identification and classification by farmers is the vital information which represent farmers’ indigenous knowledge on soil and plant relationship which is considered to be very important for biophysical suitability assessment in conventional LE. The findings from this study showed that farmers know their lands quite well, in terms of their soil quality, potential and limitations for crop productions (Table 5.1). In addition, they know how to improve their lands to be more suitable for cultivation. Even though they realize how important the soil is, farmers did not consider it as the most important factor for cultivating because they believe that they can improve the soil limitations to make it more suitable for cropping. All of these depend on cost/benefit considerations and the available inputs/resources.

Local soil names LSN 1 : Din Neau = clay LSN 2 : Din Neau pon Sai = sandy clay LSN 3 : Din Neau pon Look Rung = gravelly clay LSN 4 : Din Ruan pon Neau = clay loam LSN 5 : Din Ruan pon Sai = sandy loam LSN 6 : Din Ruan Neau pon Sai = sandy clay loam LSN 7 : Din Len pon Sai = sandy clay LSN 8 : Din pon Look Rung = laterite soil LSN 9 : Din Sai = sand LSN 10 : Din Sai pon Look Rung = gravelly sand LSN 11 : Din Dam = black soil, good soil (specify to soil colour and soil

fertility. And farmers mentioned its soil texture is clay loam)

LSN 12: Din Dam pon Sai = black soil mixed with sandy soil (specify to colour and texture)


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Table 5.1Farmers soil classification, description and crop limitations

Code Local name Descriptions Limitationsclay, reddish yellow color, poor fertility, hard when dry

lack of plant nutrients, root rot

clay, reddish black,black color, moderate fertility, sediment on top soil, good water holding capacity,somewhat poorly drained,suitable for rice

flooding, root penetration

clay, yellowish red color, moderate fertility, compaction, structureless(like liquid when wet), some soft rock on top soils, slightly hilly,cannot store water

no

clay, black color, high fertility, some cracks

clay, black color, poor to moderate fertility, compaction, sticky when wet

flooding, root penetration

sandy clay, yellow, black color , poor to moderate fertility, compaction, hard when dry, more sand in upper, shallow soils

root rot, low fetility

sandy clay, black color, moderate fertility, hard when dry,crops grow well

no

sandy clay, black color, poor fertility, some cracks,low permeability

flooding

LSN3 Din Neau pon Look Rang (gravelly clay)

gravelly clay, poor fertility, hard when dry,low permeability,located at high topographic position

gravelly,depend on rainfall

clay loam, black color, moderate fertility, hard when dry,crops grow well

flooding

clay loam, reddish brown color, moderate fertility, compaction, sediment on top soil, low permeaility

water logging

LSN5 Din Ruan pon Sai (sandy loam)

sandy loam, brown color, moderate fertility, some gravelly

no remarks

LSN6 Din Ruan Neau pon Sai (sandy clay loam)

sandy clay loam, grey color, moderate fertility salt lick, high water table

LSN7 Din Len pon Sai (sandy clay) sandy, redddish brown, black color, poor to modertae fertility, hard when dry and friable when moist, well-drained,suitable for field crops, not suitable for rice,sediment on top soils,

salt lick, high water table, yellow leaves, flooding

LSN8 Din pon Look Rang (laterite soil)

laterite soil, clay in sub soil,gravelly,hot soil,not suitable for planting

low fertility, root rot,lack of water reservoir

sand, yellow,red,brownish red, black color , poor to moderate fertility, compaction, hard when dry, more sand in upper,well-drained,suitable for field crops,not suitable for rice

run off,cannot store water,depend on rainfall

sandy, red, black color, poor to modertae fertility,well drained, not suitable for rice,sediment on top soils

salt lick,high water table,flooding

LSN1 Din Neau (clay)

LSN2 Din Neau pon Sai (sandy clay)

LSN4 Din Ruan pon Neau (clay loam)

LSN9 Din Sai (sand)


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Code Local name Descriptions LimitationsLSN10 Din Sai pon Look Rang

(gravelly sand)gravelly sand, white color, poor fertility, compaction, laterite within 1 m.,crops don't grow well

sandy

black soil, high fertility, friable when moist,located at low topographic position

no

black color, poor to moderate fertility, friable when moist,well-drained, crops grow well, sediment on top soils

cannot store water

black color, moderate to high fertlity, friable when moist,moderately well drained,crops grow well

soil erosion, mycoryza, root rot

clay,reddish brown, black color, moderate to high fertility, some cracks,friable,compaction, sediment on top soil, poorly drained,located at low topographic position

flooding

clay loam, black color, moderate fertility, some soft rock on top soils, moderately deep soils

depend on rainfall,slightly hilly so cannot store water

clay,black color, high fertility,crops grow well,located at low topographic position

flooding,,water logging

grey, black color, moderate to high fertility, friable when moist, dusty , some cracks, sediment on top soils,crops grow well

flooding

brown color, moderate fertility, moderately deep soil friable,moderately well drained,crops grow well

no

sandy clay, black color, poor to moderate fertility, friable when moist, sediment on top soilssandy clay, black color, moderate to high fertlity, some cracks, friable when moist,well-drained,crops grow well

no

LSN12 Din Dum pon Sai (black soil mixed with sandy soil)

LSN11 Din Dum (black soil)

To classify soil, farmers used the properties or diagnostic criteria as shown in Table 5.2. Texture and soil fertility were considered by farmers for all soil types. Colour, consistency, compactness, permeability, water retention, soil depth, location, soil drainage and root penetration were investigated respectively. Table 5.3 shows the farmers’ soil quality rating according to indigenous knowledge of their own land. It resulted in a final soil quality rating for each conventional LDD soil map unit.


31

Table 5.2: Soil properties of soil types considered by farmers

Soil properties/ Diagnostic criteria LSN1 LSN2 LSN3 LSN4 LSN5 LSN6 LSN7 LSN8 LSN9 LSN10 LSN11 LSN12

Colour * * * * * * * * * *Texture * * * * * * * * * * * *Fertility * * * * * * * * * * * *Soil depth * * *Soil drainage *Root penetration *Water retention * * *Permeability * * * *Cracks,consistency (hardness,stickiness, friable)

* * * * * * * *

Compactness * * * * * *Location/elevation * * Note : LSN 1-12 = Local soil names

Table 5.3: Farmers’ soil quality rating

not suitable poor medium goodPi211 12 3 2 6 1 poorPi311 11 1 2 7 1 mediumPi411 12 0 2 4 6 goodPi611 2 2 0 0 0 not suitablePi613 3 0 0 2 1 goodPi621 4 1 0 3 0 mediumPi711 3 0 1 1 1 mediumPi811 6 0 1 2 3 good

Final soil quality ratingMU countFarmers' soil quality rating for cultivation (frequency of

ranks )

5.2.2. Farmers’ land evaluation

Factors considered by farmers for assessing land suitability

The conventional LDD LE method generally evaluates land suitability only using biophysical aspects and it uses ratings of land characteristics to determine to what extent crop requirement are met. However, the interviews interestingly revealed that farmers considered not only biophysical factors but also other factors especially socio-economical factors in order to assess a LUT’s suitability (Table 5.4 and Figure 5.2.). Hence, the method used by farmers to evaluate land suitability is different from the conventional LE. It was also found that farmers considered socio-economical conditions of higher importance. Farmers evaluated the importance of biophysical factors based on their affect on crop growth, but made decisions on the basis of net benefits per unit of land. Farmers used gross margin, i.e. the value of output (yield x price) minus the variable costs (FAO, 1983) to assess the economic benefits per land unit.


32

Table 5.4: Factors considered by farmers for assessing land suitability

high importance medium importance low importanceLand use requirementCrop requirement1.Temperature 3 5.7 66.7 33.32. Water requirement in growing period 53 100 94.3 5.73.Humidity 1 1.9 1004. Soil drainage 43 81.1 79.1 18.6 2.35. Soil fertility 52 98.1 69.2 28.8 1.96. Rooting condition (root penetrate) 6 11.3 16.7 83.37 Pests & Diseases 5 9.4 40 608. Flood hazard (frequency) 14 26.4 35.7 28.6 35.7Management requirement9. Soil workability 2 3.8 10010. Potential for mechanization(Rock out crop) 1 1.9 100Other Factors1. Price/ market 38 71.7 71.1 28.92. Income,cost/profit 45 84.9 86.7 13.33. Experience 25 47.2 16 80 44. Labour 15 28.3 26.7 53.3 205. Staple food 12 22.6 83.3 16.76. Transportation 5 9.4 20 60 207. Quality of yield 13 24.5 7.7 92.38. chemical effected to health 2 3.8 50 509. Extension service 3 5.7 10010. Size of farm 10 18.9 80 20Crop yields 53 100 100

importance levelFactor considered count % of respondents


33

(a)

��

0102030405060708090

100

Water

Soil fe

rtility

Soil dra

inag

e

Floo

d ha

zard

Root p

enetra

tion

Pests

& Dise

ases

Tempe

rature

Humidi

ty

Soil w

orka

bility

Poten

tial fo

r mec

haniz

ation

��

!��"��

(b)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Wate

r

Soil

ferti

lity

Soil d

raina

ge

Floo

d haz

ard

Root p

enetr

ation

Pests

& D

iseas

es

Tempe

ratur

e

Humidi

ty

Soil

worka

bility

Pote

ntial

for m

echa

niza

tion

Factors considered by farmers

Res

pond

ents

low importance

medium importance

high importance

(c)

OTHER FACTORS CONSIDERED BY FARMERS (ESPECIALLY SOCIO-ECONOMICAL FACTORS)

0102030405060708090

100

Inco

me,co

st/prof

it

Pric

e/ m

arke

t

Exp

erien

ce

Qua

lity of yi

eld

Lab

our

Stap

le fo

od

Size o

f farm

Trans

porta

tion

Exten

sion serv

ice

chem

ical e

ffecte

d to h

ealth


% o

f res

pond

ents

(d)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Inco

me,c

ost/p

rofit

Pric

e/ mar

ket

Exp

erien

ce

Qua

lity of yi

eld

Lab

our

Stap

le food

Size

of fa

rm

Trans

porta

tion

Exten

sion serv

ice

chem

ical e

ffecte

d to h

ealth


Res

pond

ents

low importancemedium importancehigh importance

Figure 5.2: Factors considered by farmers for assessing land suitability

(a) and (b) show biophysical factors and their importance levels considered by farmers

(c) and (d) show other factors and their importance levels considered by farmers


34

Important factors farmers considered for assessing their land suitability can be identified as the following:

A. Biophysical factors were described in term of land use requirements which consisted of crop and management requirements which compare with diagnostic factors used in conventional LE.

Water requirement in growing period All farmers mentioned that the water requirement for crop growth is the most important one and it refers not only to the amount of water to be applied but also to the specific period at which the crop needs it most. In this case, farmers aware about the critical period to apply water too which is different from conventional LE where only amount of water in growing period or mean annual rainfall is normally used as parameter to assign suitability class.

Soil fertility Soil fertility is the second factor that farmers considered as very important. They understood that if a soil is fertile, crops will grow well. Even if soil fertility has a limitation by nature, the farmers thought they can overcome by applying fertilizer. To apply fertilizer, suitable amounts of fertilizer will be used depending on the amount of crop yields that farmers required and their budget for this investment. Regarding to this aspect, farmers showed their knowledge about the positive effect of the previous crop which complements to the next crop, for example, in the sequential cropping pattern of rice and tobacco, residue of nutrient in soil which had been previously applied to tobacco fields still available enough for rice growth and also straw from rice can be used for covering tobacco ditches at the beginning of planting stage in order to keep soil moisture.

Soil drainage Soil drainage is the third important factor because crops in the area i.e. rice, tobacco, maize and vegetable are affected by soil drainage constraint. A combination of crops, for example rice and tobacco, in cropping patterns also led farmers to think about the constraint of this characteristic. Rice and tobacco required different classes of soil drainage but in fact they have been grown in the same field. When farmers justified the soil drainage to be suitable for rice but not for tobacco, tobacco is stilled planted because it gives higher return. For the limitation, they can improve it by making ditches to improve soil drainage condition.

Flood hazard Farmers who have lands in the lowland which are usually affected by annual flooding stated that this factor is important because they can plant only rice in which the rice yield depends on both a period of water logging in the field and a level of water depth.

Root penetration Because of soil texture and compactness, farmers mentioned that it is difficult for root crop to penetrate.

Pests / Diseases Some farmers (9.4 % of respondents) mentioned that this factor affects the land suitability and subsequently the crop yield.


35

Temperature Farmers considered that some kinds of vegetables prefer cold temperature but they did not consider it as a limiting factor.

Humidity Only one farmer considered this factor. This farmer mentioned that humidity has no effect on crop growth, but it is important in stage of crop processing since tobacco needs suitable humid condition for drying. If it has been done in suitable condition, the quality of tobacco will be better.

Soil workability Most of farmers did not pay attention to this factor since it has no limit for cultivation, but just gives farmers a little bit difficulty for growing rice by transplanting. But for tilling, however, this is not a problem because tilling by mechanized method has been applied for a whole study area and as mentioned earlier, soil texture in many map units is now mixed with sand on the top soil.�

Rock out crop Only one farmer mentioned about this factor but it is not considered as a serious limitation. B. Other factors Income, Cost / Profit Eighty- five percent of interviewed farmers indicated that they were taking this factor into consideration to assess suitability of land, besides soil and water as mentioned before. This factor is the most important factor affecting on farmers’ decision making for selecting crop to grow. The results from their land evaluation showed that they gave higher suitability class for LUTs which give higher return per land unit. For this study, most of farmers stated that tobacco is the most profitable crop on all land units which presenting this crop grown. By a rough analysis for other crops, profit is sequentially obtained from vegetables, maize, rice, tamarind and mungbean respectively.

Farmers’ consideration on cost / profit is the similar idea as gross margin analysis in FAO guideline. Gross margin is the value of output (yield x price) minus the variable costs. It is a type of economic analysis which applied to individual land use system, that is, combination of land utilization types with land units (FAO, 1983).

Price / Market Crop price has an effect on land suitability assessment. Farmers considered that the crops which have stable price are more suitable than those which have unstable price. In addition, crops with higher price were considered to be more suitable than those with lower price. In the area, markets are available for all crops, hence it is not considered as a limitation factor. For vegetables, markets should be situated close to the fields. In this district, the vegetable market is a centre of vegetable markets in the north part of Thailand.

Experience Almost a half of respondents mentioned that this factor was considered because they have experience cultivating those crops / LUTs, so they are familiar and thought that those LUTs are suitable for their lands.


36

Labour Farmers considered labour factor differently from the FAO guideline. While, labour consideration in FAO guidelines (1983) taking into account a competition of other activities for labour, growth in labour supply etc., the farmers only considered this factor for themselves. They evaluated that they have enough time to take care those LUTs or can hire the labour just for the periods those they need.

Staple food Some respondents considered this factor because it is necessity for home-consumption.

Size of farm This factor was considered because the average farm size in the study is quite small. It is around 6.36 Rai (1.02 Ha) and 66 percent of farms are smaller than the average size. Since farmers want to achieve high income/benefit per land unit, so they take this factor into account.

Transportation In the study area, accessibility or transportation is reasonably completed both in term of infrastructure and vehicles. So, most of the farmers ignored to mention about this factor.

Quality of yield Some farmers mentioned that quality of yields in different soil types may be different such as tamarind grown in different soils give different taste, and also tobacco gives different taste and smell.

Extension services This factor was taken into account because one of the reasons that the farmers did not know the new crops or LUTs when there was no extension services.

Chemical effected to health Because of an awareness of the harmful caused by a use of chemicals, a few farmers stated that their suitability rating given for LUTs was affected especially for crops which require more chemicals such as vegetables.

C. Crop yields All of farmers considered crop yields as an important factor for giving suitability rating. This consideration is in strong agreement with FAO (1983) ,that is, crop yields are the outcome of an interaction between the land utilization type and the land unit. They are considerably influenced by management, material inputs (especially fertilizers) and cultivation practices.

Farmers land suitability The farmers land suitability ratings is presented in Table 5.5. The LUTs 1, 2, 6, 9, and 15 were asked all interviewed farmers to assess land suitabilities, the other LUTs were captured from freely response by farmers. Thus, in some map units show no data (nc). Specific details for some interesting results are described here:


37

LUT 6 (rice- tobacco (edam) -maize) was considered unsuitable in all map units because of these two main reasons. One is because there was not enough water for a whole period of planting, and another is due to a lower return benefit per land unit of maize in comparison with vegetable when it was grown as a third crop. LUT 9 and LUT 15 were considered as marginally suitable in map unit 621 because the biophysical conditions are suitable but socio-economic is not suitable. In the other map units, these LUTs were considered to be not suitable because of both the economic and biophysical reasons. For map units those are biophysical conditions possible for cultivation and farmers considered that they can achieve high benefit per land unit, the cropping patterns preferred by farmers generally are rice-tobacco-vegetable (LUT3 and LUT5), rice-tobacco(LUT2 and LUT4), maize-tobacco(LUT11), tobacco-vegetable(LUT8), and maize-vegetable(LUT10). There fore, land suitability ratings for those LUTs are higher than those for single crop such as rice (LUT1) or vegetable (LUT13).

Table 5.5: Farmers land suitability ratings

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Pi211 S3 S3 S2 nc nc N S2 nc N nc S2 nc S3 nc NPi311 N S3 S2 nc nc N nc S2 N nc nc S2 S2 S2 NPi411 S3 S2 S1 S1 S2 N nc nc N nc nc nc S3 nc NPi611 N N nc nc nc N nc S3 N nc nc nc nc nc NPi613 N N nc nc nc N nc nc N S2 S2 nc nc nc NPi621 N N nc nc nc N nc nc S3 nc nc nc S3 nc S3Pi711 S3 N nc nc nc N nc nc N nc nc nc S2 nc NPi811 S3 S2 nc nc nc N nc nc N nc S3 nc S3 nc N

Land utilization types No.Map units

Note: nc = No data, not considered

5.3. Land productivity ratings based on crop yields of actual land use

The actual yields data were collected from 53 farmers. Farmers could report amount of yield quite precisely for rice, tobacco, and maize. When rice is harvested, it is measured with hired machine. Tobacco and maize were sold at farmers’ field or farm-gate to the middlemen, so farmers could recognize amount of yields. This study took a few numbers of samples in some map units. However, most of farmers mentioned that yields of the same LUT of their neighbours are quite similar, if they applied similar management practices. More over, farmers stated that actual yields depend on water availability, soil quality, management practices such as water management, soil improvements, weed control, pest and diseases, etc. Farmers’ crop yield data is shown in Table 5.6. Yield range for land suitability classes were calculated according to percentage of reference yields as given in Table 5.7.


38

Table 5.6: Farmers’ crop yield data

Rice Tedam Tburley Maize Mungbean Coriander Cauliflower ChillyBell Peper Egg plant

Yard long bean Shallot Tamarind

Pi211 � � ��

� � ��

� � ��

� � ��

��

�� Pi311 � � ��

� � ��

� � ��

��

��

�� Pi411 � � ��

� ��

� � ��

� � ��

�� Pi611 � � ��

� �Pi613 ��

��

�� Pi621 � ��

��

�� Pi711 � � ��

� � �� Pi811 � � ��

� � � ��

� ��

��

Average Crop yields (kg/Rai)MU LUT_NO Count

Table 5.7: Suitability rating classes in term of crop yields

S1 S2 S3 N80-100% 40-80% 20-40% 0-20%

Rice 528-660 264-528 132-264 <132Tobacco(Edam) 240-300 120-240 60-120 <60Tobacco(Burley) 294-368 147-294 74-147 <74Maize 840-1050 420-840 210-420 <210Mungbean 160-200 80-160 40-80 <40Coriander 1600-2000 800-1600 400-800 <400Cauliflower 2480-3100 1240-2480 620-1240 <620Chilly 896-1120 448-896 224-448 <224Bell Peper 1400-1750 700-1400 350-700 <350Egg plant 2320-2900 1160-2320 580-1160 <580Yard long bean 2640-3300 1320-2640 660-1320 <660Shallot 1704-2130 852-1704 426-852 <426Tamarind 2000-2500 1000-2000 500-1000 <500

Crop Land suitability class


39

Table 5.8 shows the result of land productivity ratings based on crop yields of actual land use. In case of yields data of some LUTs disappeared from map units, it was implicit that those LUTs were not suitable. For instance, the LUTs consisting of rice disappear from map units Pi611, Pi613 and Pi621, it can be implied that rice is not suitable for those map units.

Table 5.8: Land productivity ratings based on crop yields of actual land use

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Pi211 S2 S2 S3 S2 S2 N

Pi311 S1 S1 S2 S1 S3 S2 S2

Pi411 S1 S1 S2 S1 S2 S3

Pi611 S3

Pi613 S1 S2 S2

Pi621 S1 S2 N

Pi711 S2 ��

Pi811 S2 S1 S1 S2

Map unitsLand utilization types No.

5.4. LDD Conventional Land Evaluation

The overall suitability of each crop for each mapping unit is shown in Table 5.9. The results have been derived from the procedure which compares the land qualities of each mapping unit or values of the diagnostic factors with the requirement of each crop which are expressed in terms of factor ratings. As already pointed out, the most limiting condition has been used to assess the overall suitability. Letter suffixes are used to indicate the limiting factors. For the LUTs which consist of 2 or more than 2 crops, the overall suitability of each LUT was combined from the final suitability class of concerned crops. The result of LDD land suitability ratings of all LUTs is shown in Table 5.10.

CO

MP

AR

ISO

N B

ET

WE

EN

CO

NV

EN

TIO

NA

L LA

ND

EV

ALU

AT

ION

AN

D A

ME

TH

OD

BA

SE

D O

N F

AR

ME

RS

’ IN

DIG

EN

OU

S K

NO

WLE

DG

E

40

Tab

le 5

.9: T

he su

itabi

lity

ratin

gs fo

r in

divi

dual

cro

ps

Lan

d ut

iliza

tion

type

: Rai

nfed

wet

land

ric

e

Con

serv

atio

n su

itabi

lity

tem

pera

ture

moi

stur

e av

aila

bilit

y ox

ygen

ava

ilabi

lity

nutr

ient

ava

ilabi

lity

soil

toxi

citie

sso

il w

orka

bilit

yer

osio

n ha

zard

( t )

( m )

( o

)( s

)( z

)( k

)( e

)

Pi21

1s1

s1s2

s1s1

s3s1

s1s3

s1s3

S3rw

ePi

311

s1s1

s1s1

s1s3

s1s1

s2s1

s2S3

rPi

411

s1s1

s1s1

s1s3

s1s1

s2s1

s2S3

rPi

611

s1s1

s2s1

s1s2

s1s1

s3s1

s3S3

we

Pi61

3s1

s1s2

s1s1

s2s1

s1s3

s1s3

S3w

ePi

621

s1s1

s2s1

s1s2

s2s1

s3s1

s3S3

we

Pi71

1s1

s1s1

s1s1

s3s1

s1s2

s1s2

S3r

Pi81

1s1

s1s1

s1s1

s1s1

s1s2

s1s2

S2w

e

mea

n te

mp.

in

grow

ing

perio

d w

ater

requ

irem

ent

in

grow

ing

perio

dslo

pe

Roc

kout

cro

pslo

pe

soil

drai

nge

Nut

rient

stat

uspH

Wor

kabi

lity

clas

sE

ffect

ive

soil

dept

hR

oot

pene

trat

ion

Map

uni

t

Lan

d qu

ality

Fina

l su

itabi

lity

clas

s

Cro

p su

itabi

lity

Man

agem

ent

suita

bilit

yro

otin

g co

nditi

ons

pote

ntia

l for

mec

hani

zatio

n( r

)( w

)

C

rop:

toba

cco

(eda

m &

bur

ley)

Con

serv

atio

n su

itabi

lity

tem

pera

ture

oxyg

en a

vaila

bilit

ynu

trie

nt a

vaila

bilit

yso

il to

xici

ties

soil

wor

kabi

lity

eros

ion

haza

rd (

t ) (

o )

( s )

( z )

( k )

( e )

Pi21

1s1

s2s1

s1s3

s1s1

s1s1

s2S3

rPi

311

s1s3

s1s1

s3s1

s1s1

s1s2

S3r

Pi41

1s1

s3s1

s1s3

s2s1

s1s1

s2S3

rPi

611

s1s2

s1s1

s2s1

s1s1

s1s2

S2or

ePi

613

s1s2

s1s1

s2s1

s1s1

s1s2

S2or

ePi

621

s1s2

s1s1

s2s3

s1s1

s1s2

S3z

Pi71

1s1

s3s1

s1s3

s2s1

s1s1

s2S3

orPi

811

s1s3

s1s1

s1s2

s1s1

s1s2

S3or

mea

n te

mp.

in

grow

ing

peri

odR

ocko

ut c

rop

slope

N

utri

ent s

tatu

spH

Wor

kabi

lity

clas

sslo

pe

Eff

ectiv

e so

il de

pth

Roo

t pen

etra

tion

Map

uni

t

Lan

d qu

ality

Fina

l su

itabi

lity

clas

s

Cro

p su

itabi

lity

Man

agem

ent s

uita

bilit

yro

otin

g co

nditi

ons

pote

ntia

l for

mec

hani

zatio

n( r

)( w

)

soil

drai

nge

CO

MP

AR

ISO

N B

ET

WE

EN

CO

NV

EN

TIO

NA

L LA

ND

EV

ALU

AT

ION

AN

D A

ME

TH

OD

BA

SE

D O

N F

AR

ME

RS

’ IN

DIG

EN

OU

S K

NO

WLE

DG

E

41

Cro

p: m

aize

Con

serv

atio

n su

itabi

lity

tem

pera

ture

oxyg

en a

vaila

bilit

ynu

trie

nt a

vaila

bilit

yso

il to

xici

ties

soil

wor

kabi

lity

eros

ion

haza

rd (

t ) (

o )

( s )

( z )

( k )

( e )

Pi21

1s1

s2s1

s2s3

s1s1

s1s1

s2S3

rPi

311

s1s3

s1s2

s3s1

s1s1

s1s1

S3or

Pi41

1s1

s3s1

s1s3

s1s1

s1s1

s1S3

orPi

611

s1s2

s1s2

s2s1

s1s1

s1s2

S2or

ePi

613

s1s2

s1s1

s2s1

s1s1

s1s2

S2or

ePi

621

s1s2

s1s1

s2s2

s1s1

s1s2

S2or

zePi

711

s1s3

s1s1

s3s1

s1s1

s1s1

S3or

Pi81

1s1

s3s1

s1s1

s1s1

s1s1

s1S3

o

mea

n te

mp.

in

grow

ing

perio

dE

ffect

ive

soil

dept

hR

oot

pene

trat

ion

Roc

kout

cro

pslo

pe

Nut

rient

stat

uspH

Wor

kabi

lity

clas

sslo

pe

MA

P U

NIT

Lan

d qu

ality

Fina

l su

itabi

lity

clas

s

Cro

p su

itabi

lity

Man

agem

ent s

uita

bilit

yro

otin

g co

nditi

ons

pote

ntia

l for

mec

hani

zatio

n( r

)( w

)

soil

drai

nge

Cro

p: m

ungb

ean

Con

serv

atio

n su

itabi

lity

tem

pera

ture

moi

stur

e av

aila

bilit

y ox

ygen

ava

ilabi

lity

nutr

ient

ava

ilabi

lity

soil

toxi

citie

sso

il w

orka

bilit

yer

osio

n ha

zard

( t )

( m )

( o

)( s

)( z

)( k

)( e

)

Pi21

1s1

s1s2

s2s1

s3s1

s1s1

s1s2

S3r

Pi31

1s1

s1s3

s2s1

s3s2

s1s1

s1s1

S3or

Pi41

1s1

s1s3

s1s1

s3s2

s1s1

s1s1

S3or

Pi61

1s1

s1s2

s2s1

s2s1

s1s1

s1s2

S2os

rePi

613

s1s1

s2s2

s1s2

s2s1

s1s1

s2S2

osrz

ePi

621

s1s1

s2s1

s1s2

s2s1

s1s1

s2S2

orze

Pi71

1s1

s1s3

s1s1

s3s2

s1s1

s1s1

S3or

Pi81

1s1

s1s3

s1s1

s1s2

s1s1

s1s1

S3or

wat

er re

quire

men

t in

gr

owin

gm

ean

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s3s3

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s2s1

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s1s1

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621

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s2s1

s2s2

s1s1

s1s1

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43

Table 5.10: LDD land suitability ratings

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Pi211 S3rwe S3rwe S3trwe S3rwe S3trwe S3rwe S3r S3tr S3r S3tr S3r S3r S3tr S3tr S3rPi311 S3r S3r S3tr S3r S3tr S3or S3r S3tr S3or S3tor S3or S3or S3tr S3tr S3orPi411 S3r S3r S3tr S3r S3tr S3or S3r S3tr S3or S3tor S3or S3or S3tr S3tr S3orPi611 S3we S3we S3twe S3we S3twe S3we S2ore S3t S2osre S3t S2ore S2osrze S3t S3t S3rPi613 S3we S3we S3twe S3we S3twe S3we S2ore S3t S2osrze S3t S2ore S2osre S3t S3t S2orPi621 S3we S3zwe S3tzwe S3zwe S3tzwe S3zwe S3z S3tz S2orze S3t S3z S3z S3t S3tz S2orPi711 S3r S3or S3tor S3or S3tor S3or S3or S3tor S3or S3tor S3or S3or S3tr S3tor S3orPi811 S2we S3or S3tor S3or S3tor S3or S3or S3tor S3or S3to S3or S3or S3t S3tor S3o

Map units

Land suitability assessment based on conventional land evaluationLand utilization types No.

According to Table 5.10, the land qualities or diagnostic factors presenting as the most limiting factors for LUTs in the study can be described as the following: Temperature regime (t) The mean temperature in growing period limits to growth of vegetable (cauliflower). Most of the LUTs which consist of vegetable were rated as S3 because of this factor. But only LUT 12 that vegetable had been grown in colder period so the suitability rating for this LUT was rated as S2. Moisture availability (m) For the study, water requirement in growing period for some LUTs was not considered. Because it was assumed that if farmers could grow these LUTs, so water should be available. This condition was assumed based on field survey data which presenting available water resources in the area such as canals, farm ponds, and artesian wells. Rooting conditions (r) In the study, root penetration became a limiting factor. All crops/LUTs prefer ease for root penetration. But soil texture in the area is mostly heavy soils which is difficult for root penetration. Oxygen availability (o) Soil drainage class is a representative for the assessment. The result shows that this condition became a limitation for field crops and sweet tamarind in poorly-drained soils. Soil toxicities (z) This quality was represented by pH. In map unit Pi621, its pH value is neutral to moderately alkaline which limits to many LUTs. Potential for mechanization (w) The condition of land which acts as limitation to mechanization for this study is slope. The LUTs which consist of rice are limited by slope condition in map units Pi211, Pi611, Pi613, and Pi621. This consideration is different with farmers’ LE, rice was considered not suitable in these map units because these areas can not store water for rice planting.


44

Erosion hazard (e) The characteristic used for erosion assessment is slope, which is the same as assessment for potential for mechanisation, thus the result is the same.

Table 5.11 : Comparison between the factors considered by farmers and the diagnostic factors used by LDD for assessing land suitability.

Land qualities/Land use requirements Diagnostic factors LDD FARMERS

Temperature Mean Temp.in growing period + *Moisture availability Mean annual rainfall, Water

requirement in growing period+ *

Oxygen availability Soil drainage + *Nutrient availability Nutrient status + *

Effective soil depth +Root penetration + *

Flood hazard Flooding frequency *Soil toxicity Reaction in undation

condition(pH)+

Soil workability workability class + *Slope +Rock out crop + *

Erosion hazard slope +Humidity *Pests & Diseases *

Rooting condition

Potential for mechanization

Note: + The diagnostic criteria used by LDD * The factor considered by farmers Table 5.11 shows the factors considered by farmers and the diagnostic criteria used by LDD for assessing land suitability. Only the interesting factors would be discussed as the following. Temperature This factor was considered as a limiting factor for vegetable (cauliflower) in LDD LE but it was not considered as a limiting factor by farmers. Water requirement in growing period This factor was considered as a very important limiting factor by farmers. But for LDD LE method, water requirement in growing period for some LUTs was not considered. Because it was assumed that if farmers could grow these LUTs, so water should be available. This condition was assumed based on field survey data which presenting available water resources in the area such as canals, farm ponds, and artesian wells.


45

Soil drainage This factor was considered as a limiting factor by both methods. The result on soil-plant relationship based on this factor is similar from both methods such as rice prefers somewhat poorly drained to very poorly drained soils while field crops and vegetables prefer well drained soils. Root penetration This factor was considered as a limiting factor by both methods, especially for tobacco and vegetables. Flood hazard This factor was considered as a limiting factor by farmers who were affected by this condition. But LDD LE did not taken this factor into account due to no data available. Soil toxicities This factor was considered only by LDD but not by the farmers. Potential for mechanization Only one farmer considered this factor as a non-serious limiting factor. The characteristic used was rock out crop which is different with diagnostic criteria used by LDD. Regarding to the LDD LE, this factor was acted as a limiting factor which represented by slope angle. Erosion hazard This factor also represents by slope. It was not considered by farmers, but it is a limiting factor in the LDD LE. Farmers consider slope in other meanings, for instance; in slope area cannot store water, so it is not suitable for rice.

5.5. Comparative results of both LE methods with the land productivity ratings based on crop yields of actual land use.

The land productivity ratings based on crop yields of actual land use is considered as a means to assess the derived suitabilities for both LE methods. Outputs will be used as yardsticks to compare the outputs of LDD LE and the LE based on farmers’ indigenous knowledge.

To compare the results from both LE methods with the land productivity ratings, five LUTs from the original fifteen LUTs, were selected. The five LUTs were given suitability ratings by all interviewed farmers as mentioned in section 4.2.2 are listed below:

• LUT1: Rainfed wetland rice • LUT2: Sequential cropping patterns: Rice-Tobacco (Edam) • LUT6: Sequential cropping patterns: Rice-Tobacco (Edam)-Maize • LUT9: Sequential cropping patterns: Maize-Mungbean • LUT15: Sweet tamarind


46

5.5.1. Assessment of LE based on farmers’ indigenous knowledge

Table 5.12 reports of the five LUTs, which agreement and disagreement between the farmers’ land suitability ratings and the land productivity ratings. Map units, which occur in both methods, are indicated in the table.

Table 5.12: Comparison between the farmers’ land suitability ratings and the land productivity ratings

S1 S2 S3 NS1S2S3 �� N ��

S1S2 �� S3 �� N ��

S1S2S3N ��

S1S2S3 ��N

S1S2S3 ��N ��

LUT9:��

LUT15: ��

LE b

ased

on

FK

Suitability based on crop yields

LUT1:�� !�

LUT2:��!��"#��!!#�$%��&

LUT6'��!��"#��!!#�

$%��&��

According to table above can be explained the results as the following.

Rainfed wetland rice

All the farmers’ land suitability ratings are underestimated compared to those based on crop yields. Like in map unit Pi411 and Pi311, even though land suitability class based on crop yields is presented as S1 class, but farmers’ land suitability classes are given as S3 and N respectively. All of this is because the soil quality in these map units is suitable for rice where they can give high yields. Nevertheless, farmers gave lower suitability classes since they considered more on economic aspect especially profits per land unit rather than on biophysical aspect. They thought that they can not earn any profits by growing rice only because it will be used just for home-consumption and only the excess will be sold.

For map units Pi211, Pi711 and Pi811, land suitability class based on crop yields come closer to farmers’ land suitability class because some areas in these map units encountered flooding and have a low yield as a result.


47

Rice-Tobacco (Edam)

The result also shows an underestimate of farmers’ land suitability ratings for LUT2 (rice-edam tobacco) compared to the land productivity ratings, even though farmers achieved high yields and high profits per land unit from this LUT. Many interviewed farmers gave suitability ratings for this LUT as moderately suitable class. The reasons as mentioned by them are because they have to treat tobacco as intensive crop and add inputs especially fertilizer normally at intermediate to high level. Since, they have to improve some physical conditions and practice good managements for this LUT, so they justified it not to be actually highly suitable by itself. If we compare between map units which represent land suitability class based on crop yield as S1, the results can be explained as such, farmers rated soil quality for map unit Pi411 and Pi 811 as good soil and Pi311 and Pi711 as medium soil. For Pi711, since partially of this area was faced with flooding problem, so the result is related to biophysical conditions concerned. For the result assessed on map unit Pi211, farmers rated it as poor soil which is in agreement with crop yields which are lower than others.

Rice-Tobacco (Edam)-Maize

The farmers’ land suitability rating for LUT6 (rice-edam tobacco-maize) is in not suitable class, while the land productivity rating is in S1. The farmers considered maize to be not suitable as a third crop because firstly, if they want to grow maize as the third crop they must have a well plan of planting period to match with a moisture period of the area otherwise they should have enough available water resources for a whole period; secondly, growing maize should have a big area because maize gives low benefit per land unit. In this case, they preferred to grow vegetables as a third crop instead of maize because a vegetable crop cycle is shorter than maize and it also gives higher benefit per land unit.

Maize-Mungbean

The result shows that only map unit Pi621 has grown this LUT (maize-mungbean) and the results for the land productivity rating is S1, while for farmers’ land suitability rating is S3. The reasons, which caused farmers’ land suitability rating to be underestimated compared to the land productivity ratings, are because farmers considered many factors involved. Those factors are, for instance, soil is suitable but gives low benefit per land unit, and mungbean requires high labour in harvesting period. Besides, farmers’ land suitability ratings for other map units are not suitable but they are not presented in the Table since the LUT did not present in those areas so there was no yield data. For obvious reasons, yield data will be missing from not suitable land (FAO, 1983).

Sweet tamarind

The result shows that the LUT15 (sweet tamarind) is presented in map unit Pi621 and Pi211 where both of them are classified for their land suitability classes based on crop yields as not suitable. For obvious reasons, yield data was low because the farmers who grew this LUT are in the old age; they did not take profits into consideration also they did not take a good care of their farms. By comparing within these two map units, the farmer in map unit Pi211 was found to take profit into considerations at a greater extent than another. However, in spite of these reasons, farmers’ land suitability rating for map unit Pi621 was still rated as S3 because of soil quality, weather, yield, labour used and price.


48

5.5.2. Assessment of LDD LE

Table 5.13 shows the agreement and disagreement between the LDD land suitability ratings and the land productivity ratings. The map units, which occur in combination of both methods, were indicated in the tables. Almost the LDD land suitability ratings are lower than the land productivity ratings. Only the suitability rating for rainfed wetland rice in map unit Pi811 was found to present at the same class, and a contrary case for sweet tamarind given in map unit Pi621 in which LDD land suitability ratings are higher than the land productivity ratings. The reasons to explain why those LDD land suitability ratings were underestimated as compared to the land productivity ratings could be explained by some findings i.e. (1) In LDD LE, many land qualities or diagnostic factors were taken into consideration by using limiting conditions method to combine land suitability rating. Thus, an occasion of appearing limitations from some factors is high. Many results of LDD land suitability ratings (see table 5.10) present limitations from root penetration (r) which related to soil texture and other limitations such as potential for mechanization (w) and erosion hazard (e) which related to slope. For slope found in four map units out of all eight map units, they are consisting of wide range of percent slope, which can be assigned to two slope classes, thus the final slope class of those map units will be assigned to the upper value of percent slope. This event had an effect on suitability class of the specific LUTs in matching process. Though in reality, these factors do not affect on crop productivity or crop yields much, since in practical, farmers improved the biophysical conditions to be suitable for crops such as ploughing with mechanized machines, making ditches, etc. Generally, in the study area farmers applied inputs and technology at intermediate level; (2) the LDD LE method strongly depended on secondary data and may be less field checks (3) the LDD LE strongly depended on justification of the land evaluators to justify which land qualities are significant to crop productivity and crop yields, and also in the step of combining land suitability ratings in order to justify an over all suitability whether to belong to which classes.


49

Table 5.13: Comparison between the LDD’ land suitability ratings and the land productivity ratings

S1 S2 S3 NS1S2 ��S3 �� N

S1S2S3 ��

�� N

S1S2S3 ��N

S1S2 ��S3N

S1S2 ��S3 ��N

Suitability based on crop yields

LDD

LE

LUT1:�� !�

LUT2:��!��"#��!!#�$%��&

LUT6'��!��"#��!!#�

$%��&��

LUT9:��

LUT15: ��


50

6. Discussions

(1) Based on the LE methods cross tables, the land productivity ratings are consistently higher than suitability rating of both LE methods. This is caused by, farmers’ cultural practices at intermediate level, which influenced directly the crop yields. As stated by FAO (1983), crop yields are the outcome of an interaction between the land utilization type and the land unit. They are considerably influenced by management, material inputs (especially fertilizers) and cultivation practices; yields at intermediate to high input level can be 3-5 times more than those at traditional levels. Both LE methods underestimate land suitability, farmers’ LE consider many factors (section 5.2.2) and based rating more on economic factors than bio-physical ones. LDD LE rated only biophysical conditions. However, as Ryder (2003) indicated existing agricultural patterns do not necessarily reflect biophysical land suitability because farmers with a profound knowledge of environment conditions may establish a crop on inappropriate land for overriding socio-personal or economic reasons.

(2) Land evaluation is based on technology transfer. Many tools can be applied at different scale such as local level (field and micro-watershed), regional level (watershed), national level (sectorial policy implementation, market studies, large watershed). Each level has its own objectives and degree of detail, but the guiding principle remains the same: evaluation of land use alternatives to obtain a higher degree of sustainability. This study focuses on land evaluation at field level and tends to incorporate farmers’ indigenous knowledge and their constraints and preferences. In case some new crops or LUTs are proposed for a particular area, farmers’ indigenous knowledge can not be incorporate since farmers do not know the proposed LUTs. If such proposed crops or LUTs are evaluated as suitable, then they have to be tested at a research station to ensure biophysical suitability under local conditions. The proposed crops or LUTs should be introduced or demonstrated to farmers and experiment plots as outreach programme should be selected on advanced farmers’ fields. Cools, et al. (2003) mentioned that adaptation of land use to the potentialities and constraints of local agroecologies is a key principle of sustainable land management. Farmers and land resources professionals assess the options that optimise the productivity and sustainable land use through different knowledge systems. The farmers’ knowledge provided a better understanding of the impact of microclimatic variations on crop productivity and it would be complementary to scientific knowledge. On the other hand, socio-economic suitability also has to be analysed. Generally, smallholder farmers tend to avoid risks when making decision about their farm plans especially for adopting new crops or LUTs and they are sensitive to productivity and economic ( monetary ) returns as well(van Laake & Rossiter, 1998). Therefore, it is important to understand the social-culture context, which determines attitudes toward risk, innovation, and markets. To evaluate both aspects, a participatory approach is proven as very useful. In addition, Rossiter (1996) mentioned that before any inventory and evaluation project is undertaken, a demand-driven approach, whereby the real need and options open to decision-makers must be followed. All these to make sure that land use alternatives will match with real problems and social orientations.


51

In conclusion, even though in case of proposing new crops or LUTs, farmers’ indigenous knowledge can contribute to LE methods. Moreover, farmers will adopt new LUTs easier with their participation in the process.

(3) The strengths and weaknesses of the LDD LE

The findings from LDD LE can be discussed on the point of strengths and weaknesses as follows:

Strengths: • This method is systematic. It can be applied at different levels of detail, according to the

objectives and the scale of the evaluation. • The limiting conditions method, which is used in this study for combining land suitability

ratings, gives results related directly to crop growth and crop yield. Weaknesses:

• This method is complex and requires close cooperation between natural resource scientists, agronomists, agro-socio-economist, etc.

• Socio-economic aspects are seldom considered. • Land use types or crops are generally selected on the basis of general considerations and less

attention on problem analysis of the area. Normally, current LUTs are selected. Fresco et al.(1989), mentioned that a constraint of the LE methodology itself is the lack of clear procedures for the selection of land use types. To make this step clearer and produce results which fit better with local environments, consideration of interest groups, especially farmers and their involvement during problem analysis and LUT selecting is necessary. The approach of LUT selection by using key attributes: a structure approach to LUT selection that builds on object-oriented problem analysis is invaluable (Figure 4.4) (de Bie, 2000).

• This method is strongly depending on justification of land evaluators especially during matching. They have to know exactly what are critical values of the land use requirement/ land qualities with respect to certain productivity levels, and also during assigning overall land suitability ratings.

• This method actually depends on secondary data (technology transfer). If the data used is out of date, so the results of LE will not be correct and be less reliable.

(4) The merits of LE based on farmers’ indigenous knowledge

The findings from LE based on farmers’ indigenous knowledge can be discussed on the merit aspect of this method as the following:

• The biophysical factors which are considered at high important level by farmers (Table 5.4) critically affect crop productivity and yields, i.e., water in growing periods, soil fertility, soil drainage, flood hazard, and root penetration.

• Farmers’ land suitability factors were rated by different weights each. Firstly, farmers considered a possibility on biophysical conditions i.e., water and soil, etc. and then finally, gave more weight for economic aspect especially for profit per land unit. This finding is in strong agreement with Cools (2003) ,who stated that the farmer-led land suitability assessment procedure explained adequately the overriding weight of socio-economic constraints over biophysical opportunities.

• Besides their indigenous knowledge, the information which farmers used to assess land suitability is up to date and reflects the real conditions on both biophysical and socio-


52

economic conditions. This information made the results of farmers’ LE more reliable and close to actuality.

Some notes on the mismatch of the LDD soil map (characteristics used by soil scientists) and soil classification by farmers’ indigenous knowledge than also the spatial extend of soil units differs for both LE methods. The farmers’ soil map depends more on supplying conditions, while the LDD map is focused on static soil properties that often poorly relate to crop productivity and remedial management practices.


53

7. Conclusions and Recommendations

7.1. Conclusions

The findings from the research are presented in this section on the basis of the objectives and research questions.

(1) LDD generally rates land suitability on biophysical factors only and taking into account the most limiting factor as final determinant. (As mentioned in section 5.4)

(2) The farmers assess their land suitability by taking both biophysical factors and socio-economic factors into account; they rate more weight on the latter factor. The most important factor on biophysical aspect is water requirement during the growing period whereas profit per land unit is being considered as the most important socio-economic aspect.

Farmers evaluated the importance of biophysical factors based on their affect on crop growth or on productivity, but made decisions on the basis of net benefits per unit of land. Because of they tend to avoid risks when making decisions about their farm plans.

Besides their indigenous knowledge, the information used for farmers’ LE is up to date and reflects the real conditions on both biophysical and socio-economic conditions. This information made the results of farmers’ LE more reliable and close to actuality.

(3) Farmers clearly understand on land use system, their environments, and context which influencing their decision to farm. They also can provide information which has been overlooked by land evaluators.

So, bringing together these two areas of conventional knowledge and farmers’ indigenous knowledge may provide a more complete of LDD conventional land evaluation.

(4) Farmers’ indigenous knowledge can be applied to improve the LDD conventional LE in the following processes:

• Selection of Land use types. • In steps of land quality and land characteristics selection and matching between land qualities

and land use requirements, the factors those farmers considered as important and really have an effect on crop productivity should be accounted for.

• More attention should be given to socio-economic analysis because it is the most important criteria for farmers to decide which crops to grow and how suitable to use the lands for.

• In a reiteration process of LE, farmers’ indigenous knowledge on land improvement and land management should be considered because these practices affect a suitability of land unit.


54

7.2. Recommendations

Because of the findings from the research, therefore, the LDD LE is suggested to improve to become a more complete LE. Moreover, the improved LDD LE will be served a requirement of Ministry of Agriculture and Cooperatives that wanted to create the agricultural plans at sub-district level. Hence, LDD should be extended the procedures of LE by following the FAO Guidelines and paid more attention on farmers’ indigenous knowledge and prevailing conditions in these following processes:

(1) Selection of land utilization types. (2) Incorporation of crop yield data. (3) Consideration on land improvement. (4) Economic and social analysis. (5) Field check. (6) Modification of land evaluation reports and maps by using non technical terms e.g. by a use

of local soil names which are commonly known in all regions.


55

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Huizing, H., Bronsveld, M. C., Chandraptaya, S., Latham, M., Omakupt, M., Panichpong, S., et al. (1994). Knowledge transfer to farmers and the use of information system for land use planning in Thiland. In The future of the land:Mobilising and integrating knowledge for land use option: John Wiley and Sons.

LDD. (1999). Manual of qualitative land evaluation. Bangkok: Land Development Department.

Mae JoeTobacco Experiment Station. (2004). Annual Report , 2004. Chiang Mai: Thailand Tobacco Monopoly, Ministry of Finance.


56

Mafalacusser, J. M. (1995). The use of indigenous knowledge for land use planning in a part of Xai - Xai district Gaza province, Mozambique. Unpublished MSc Thesis, ITC ,Enschede.

Omakupt, M., & Huizing, H. (1992). Land evaluation and land use planning. Paper presented at the Workshop on GIS and RS for Natural Resources Management by ILWIS, Thailand.

Phetchabun Provincial Statistical Office. (2004). Statistical reports of changwat, 2004. Phetchabun, Thailand.

Rossiter, D., G. (1996). A theoretical framework for land evaluation. Geoderma, 72(3-4), 165-190.

Ryder, R. (2003). Local soil knowledge and site suitability evaluation in the Dominican Republic. Geoderma, 111(3-4), 289-305.

Siderius, W., & Mafalacusser, J. (1998). Indigenous Soil Knowledge as an input to Land Evaluation. Paper presented at the Proceeding 16th World Soil Science Congress, Montpellier, France.

Soil Survey and Classification Division (Cartographer). (1988). Semi-detailed soil map of Lom Sak and LOm Kao District, Phetchabun Province

Soil Survey Division (Cartographer). (1976). Detailed Reconnaissance Soil Map of Phetchabun Province.

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van Laake, P., E.,, & Rossiter, D., G. (1998). An integrated framework for land evaluation with soil conservation components in Costa Rica. Conservation voice : Listening to the land, 1 (2) April / May 1998, 26-30.

Vargas Rojas, R. J. (2004). A participatory land suitability assessment using integrated toposequence analysis :Namchun sub-watershed, Petchabun Province, Thailand. Unpublished Msc. Thesis, ITC,Enschede.

Winklerprins, A. M. G. A. (1999). Local soil knowledge: A tool for sustainable land management. In Society &Natural Resources,12 (pp. 151-161): Taylor & Francis.

Yimyam, T. (1986). Comparison of actual field yields of cauliflower varieties: Mae Joe University, Chiengmai, Thailand.


57

Appendices

Appendix 1: Field data capture form

FORM FOR CAPTURING FARMERS’LAND EVALUATION Date: __________________ Interview no.: ____ Name of respondent: ______________________________________Age________yrs. A) GENERAL INFORMATION Location Coordinate: X _______________ Y________________ Mapping unit: _______________ Size of plot: Rai ___________ Ha_________ Village: _____________________ District______________________________ Remarks: __________________________________________________________ B) FARMERS’ SOIL PERCEPTION Local name: ____________________________________ Properties: __________________________________________________________________________________________________________________________________________ ________________________________________________________________________ Difference with other soil types: 1.__________________________________________________________________________ 2. ______________________________________________________________________ 3. ______________________________________________________________________ ________________________________________________________________________ Classification of soil quality: (good, moderate, poor, and not suitable for cultivation): ________________________________________________________________________ Reasons: ____________________________________________________________________________________________________________________________________________ Soil problems encountered: ___________________________________________________________________________ Soil field-testing: 1 Soil texture (feel method):__________________ 2. Soil pH:_________________________________


58

C) CROP AND LAND SUITABILITY PERCEIVED BY FARMERS 1. Do you think which crops/cropping patterns/LUTs are suitable for your field? Why? 2. Can you rank it in order or give suitability rating for each LUT? 3. Why you rank it or give suitability rating like that?

Suitability rating Crop/ Cropping pattern/ LUTs

High Moderate

Marginally

Not suit.

Reasons/comments

More explanation about the factors which affecting to crop production: Biophysical factors: ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Other factor :( such as market, capital, benefit, transportation, extension services, etc.)________________________________________________________________________________________________________________________________________________________________


59

D) LAND SUITABILITY ASSESSMENT BASED ON CROP YIELD OF ACTUAL LAND USE Which crops do you grow in your field? (Or take a list for crops planted at the moment of interview) Why do you grow it? (Confirm for actual land use) How much of crop yield that you get? And please give rating. Crops produce (2003-2004)

Rating of yield LUTs/ Crop grown

Area planted (Rai)

Yield ( kg/Rai) High Medium Low Nil

Reasons

In case of the crop grown is absolutely different with suitable crops, which he/ she mentioned before. Then ask this question: Why you don’t grow it?

Suitability rating Crop/ Cropping pattern/ LUTs high moderat

e marginally Not

suit.

Reasons/factor limitations

5. How do you manage your crops to reach the amount of yield?


60

CROP MANAGEMENT Crop calendar (operation period_____________________________________) Crop grown

Jan. Feb. Mar.

Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.

LAND MANAGEMENT

Preparations Power source: ___________________________________________________________ Labor input: _____________________________________________________________ Sowing Seed quantity &quality: ____________________________________________________________ Labor input: _____________________________________________________________ Planting Fertilizer used: ________________________________________________________________________________________________________________________________________________________________________________________________________________________ Weed & Pest control: ________________________________________________________________________________________________________________________________________________________________________________________________________________________ Labor input: ________________________________________________________________________________________________________________________________________________ Harvesting


61

Labor input: ________________________________________________________________________________________________________________________________________________ Others: ________________________________________________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________________________________ 6. What are the important factors that affecting to crop yields? And why?


62

Appendix 2: Land use requirements for the selected land utilization types

Crop: rice

LAND-USE REQUIREMENT

FACTOR RATING

LAND QUALITY Diagnostic factor Unit s1 s2 s3 n o C 22-30 31-33 34-35 >35 TEMPERATURE

(t) Mean temp. in growing period

20-21 18-19 <18

MOISTURE AVAILABILITY (m)

Water requirement in growing period

mm.

650-800 450-650 350-450 <350

OXYGEN AVAILABILITY (o)

Soil drainage

class

1,2,3 4 5 6

NUTRIENT AVAILABILITY (s)

Nutrient status

class

VH,H,M L VL -

Soil depth cm.

>50 25-50 15-25 <15 ROOTING CONDITIONS (r)

Root penetration class

1,2 3 4 -

pH 5.6-7.3 7.4-7.8 7.9-8.4 >8.4 SOIL TOXICITIES

(z) Reaction

5.1-5.5 4.5-5.0 <4.5

SOIL WORKABILITY (k)

Workability class (Top soil)

class

1,2 3 4 -

Slope class

A B C >C POTENTIAL FOR MECHANIZATION (w) Rockout crop

class 1 2 3 4

EROSION HAZARD (e)

Slope class

A B C >C


63

Crop: tobacco

LAND-USE REQUIREMENT FACTOR RATING

LAND QUALITY Diagnostic factor Unit s1 s2 s3 n o C 22-30 31-

32 33-35

>35 TEMPERATURE (t) Mean temp. in growing period

17-

19 13-16

<13


Water requirement in growing period mm.

400-600 300-400

200-300

<200


Soil drainage class

5,6 4 3 1,2


Nutrient status class

VH,H,M L -

Soil depth cm.

>50 30-50

20-30

<20 ROOTING CONDITIONS (r)


1,2 3 4 -

pH 5.6-6.5 6.6-

7.3 7.3-8.4

>8.4 SOIL TOXICITIES (z) Reaction

5.1-

5.5 4.5-5.0

<4.5

SOIL WORKABILITY (k) Workability class(Top soil) class

1,2 3 4 -

Slope class

A,B,C D E >E POTENTIAL FOR MECHANIZATION (w)

Rockout crop class

1 2 3 4

EROSION HAZARD (e) Slope class

A B,C D >D


64

Crop: maize


LAND QUALITY Diagnostic factor Unit s1 s2 s3 n o C 24-30 31-

32 33-35


20-

23 16-19

<16


Water requirement in growing period mm. 400-600 300-

400 200-300 <200


Soil drainage class

5,6 4 3 1,2



VH,H,M L VL -

Soil depth cm.

>100 50-100



1,2 3 4 -

pH 5.1-7.3 7.4-

7.8 7.9-8.4

>8.4 SOIL TOXICITIES (z) Reaction

4.5-

5.0 4.0-4.4

<4.0

SOIL WORKABILITY (k) Workability class (Top soil) class

1,2 3 4 -

Slope class

A,B,C D E >E POTENTIAL FOR MECHANIZATION (w)

Rockout crop class

1 2 3 4


A,B C D >D


65

Crop: mungbean


LAND QUALITY Diagnostic factor Unit s1 s2 s3 n

o C 20-30 31-33

33-35


17-

19 15-16

<15


Water requirement in growing period mm.

350-500 250-350

200-250

<200

OXYGEN AVAILABILITY (o) Soil drainage class

5,6 4 3 1,2



VH,H M,L -

Soil depth cm.

>50 30-50

15-30



1,2 3 4 -

SOIL TOXICITIES (z) Reaction pH

5.6-6.5 6.6-7.8

7.9-8.4

>8.4

5.1-5.5

4.5-5.0

<4.5


1,2 3 4 -

POTENTIAL FOR MECHANIZATION (w)

Slope class

A,B,C D E >E

Rockout crop class

1 2 3 4


A,B C D >D


66


LAND QUALITY Diagnostic factor Unit S1 S2 S3 No C 15-20 10-15 5-10 <5

20-25 25-30 >30

600-1100 450-600 <450

1100-1900 >1900

OXYGEN AVAILABILITY (o) Soil drainage class 5,6 3,4 2 1

NUTRIENT AVAILABILITY (s) Nutrient status class H M L L

ROOTING CONDITIONS (r) Soil depth cm. >150 50-150 20-50 <20

Root penetration class 1,2 3 4

pH 6-7 5.5-6 8-8.5 >8.5

7-8

SOIL WORKABILITY (k) Workability class(Top soil) class 1,2 3 4

Slope class A,B,C D E >E

Rockout crop class 1 2 3 4

EROSION HAZARD (e) Slope class A,B C D >D


SOIL TOXICITIES (z) Reaction

Mean temp. in growing period

Ann. Rainfall

Vegetable (Cauliflower)

TEMPERATURE (t)

MOISTURE AVAILABILITY (m)mm.


67

Crop: tamarind


LAND QUALITY Diagnostic factor Unit s1 s2 s3 n o C 26-28 29-32 33-

35 >35 TEMPERATURE (t) Mean temp. in growing

period

24-25 20-

23 <20

mm. 1200-1600 1600-

1800 - >180

0 MOISTURE AVAILABILITY (m)

Ann. Rainfall

900-

1200 700-900

<700


Soil drainage class

5,6 4 3 1,2



VH,H,M L -

Soil depth cm.

>150 100-150

50-100



1,2 3 4 -

SOIL TOXICITIES (z) Reaction pH

6.1-7.3


1,2 3 4 -


Slope class

A,B,C D E >E

Rockout crop class

1 2 3 4


A,B,C D E >E


68

Appendix 3: Codebook for the terms and keys used in the study

Code Explanation/Source/Other info TypeGeneral

()*)+ (��,�� )#��

- ."��%�/��$01��&�2�1�� #

3 ."��)#��4��$01��&2�1�� #

�%�� "4��#��4��,��2��,�� )#��

5(6

"4��#��4��7 �!��4��4��,��/�!#��!��2��,��2�

�#7#��7 )#��

8(�" �8�/��!��4��4��,� ��/� #!��2��,�� )#��

�6"9*�

"4��/��#��4��7 #��:7��//��4�!4��;��4��/7#��4� ��

�4��,��/�!#��!��2��,��$<��=��>�!��& ��#

?1

"4��;7��#��!�#7��#��4��/7#��@/�7 #��4��/�7��/��4� ��4��

��,��/�!#��!��2�#�/��,��#�� )#�� Mapping Unit

�.

��77��4��!#��/7#��#��/#� ��;7�/��4�!4��/��/��/��4��/��

��#��4��/��;�2��#7��# #��!��7�$�/!� ��'�� & )#�� Soil information/description

TXf"#7�/#� ��:��A��#��4��/7#��@7 #��4�!4�! �/��;��;�� 4#��

#��4��/��!4��2�� )#��

"-�

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��,�� )#��

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/ /��;� #�� )#��

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! ! �;� #�� )#��

! ! �; )#��

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"#7�/#� �7>�,� ��/��A��#��4��7 #��/!��2�?4��!� �

��4#� +��

7>/ "#7�/#� �7>�,� ��/��A��#��4��7 #��/!��2�/#� ��7 +��

6?/ 6��!4��!��/��!/2/#� ��7

�#� ��! �//

� 5��;�7##� ;�� +��

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� �#��4��7##� ;�� +��

� �#�� ;�7##� ;�� +��

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69

Code Explanation/Source/Other info Type6�) 6#!� ��#��4��/#� ��,��;��4��/7#��2��,��

6�)�� 8��)��=��! �; )#��

6�)�� 8��)��7#��=��/��;�! �; )#��

6�)�� 8��)��7#��6##A��=��,� ;�! �; )#��

6�)�� 8��7#��)��=��! �;� #�� )#��

6�)�� 8��7#��=��/��;� #�� )#��

6�)� �8��)��7#��=��/��;�! �;� #�� )#��

6�)�� 8��6��7#��=��/��;�! �; )#��

6�)�� 8��7#��6##A��=�� /#� )#��

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6�)�� 8��8��=�� !A�/#� ��##��/#� )#��

6�)��

�8��8��7#��=�� !A�/#� ��:��4�/��;��

��/#� )#��

��+�

��#7��/�#��4��/#� �!� ��,��4�!4��:7 ��;��4��/7#��2�

��,�� )#��

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� 1##� +��

� �� +��

7 �##� +��

� )#��/�� +�� LUT 6�� #��;7�

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6."� Sequential cropping patterns: Rice-Tobacco (Edam) )#��

6."� Sequential cropping patterns: Rice-Tobacco (Edam)-Vegetables )#��

6."� Sequential cropping patterns: Rice-Tobacco (burley) )#��

6."� Sequential cropping patterns: Rice-Tobacco (burley)-Vegetables )#��

6." Sequential cropping patterns: Rice-Tobacco (Edam)-Maize )#��

6."� Tobacco (burley) )#��

6."� Sequential cropping patterns: Tobacco (Edam)-Vegetables )#��

6." Sequential cropping patterns: Maize-Mungbean )#��

6."�� Sequential cropping patterns: Maize-Vegetable )#��

6."�� Sequential cropping patterns: Maize-Tobacco (Edam) )#��

6."�� Sequential cropping patterns: Maize-Tobacco (Edam)-Vegetables )#��

6."�� Vegetables )#��

6."�� Sequential cropping patterns: Vegetable-Tobacco (Edam)-Vegetable )#��

6."�� Sweet tamarind )#��


70

Appendix 4: General key informant data

IN_NO MU X Y RESPONDENT VILLAGE DISTRICTPLOT SIZE (Rai)

CROP GROWN

1 Pi211 736046 1858521 Sriwai Pimnak Bung Tai Lom sak 3 sticky rice2 Pi711 736347 1859024 Ham Bautong Huai Kok Lom sak 6 rice3 Pi711 736484 1858908 Prachum Promee Bung Tai Lom sak 14 rice4 Pi711 736526 1858939 Thawan Rugsasri Rong Tabaek Lom sak 13 sticky rice5 Pi211 733251 1855453 Mai Pitiso Rongchuak Lom sak 2 sticky rice6 Pi211 733278 1855523 Bunhome Gundok Nam Ko Thai Lom sak 2 tobacco7 Pi211 734234 1854981 Kamla Poomyai Nam Ko Thai Lom sak 2 tobacco8 Pi211 731306 1856308 Sommai Duangpila Muang Mai Pattana Lom sak 4 sticky rice9 Pi411 732205 1859036 Samnaing Pengpad Huai Pun Lom sak 16 sticky rice

10 Pi211 731293 1860522 Tum Wongpang Huai Pun Lom sak 3 tobacco11 Pi621 731221 1860273 Uraiwan Ladta Huai Pun Lom sak 3 bell peper12 Pi411 736138 1855894 Gaesorn Trupmak Dong Khoi Lom sak 2 rice13 Pi411 736143 1855975 Utan Hanluk Dong Khoi Lom sak 2 egg plant14 Pi411 734840 1855878 Somsak Gatetong Nam Ko Thai Lom sak 8 sticky rice15 Pi211 733956 1857280 Sompong Plongkaew Nam Ko Set Lom sak 6 sticky rice16 Pi311 730876 1858337 Khayai Luanloy Nam Ko Yai Lom sak 5 sticky rice17 Pi311 732054 1857731 Seela Wanpeng Nam Ko Lom sak 3 cauliflower18 Pi311 731996 1857799 Wanchart Tongyern Nam Ko Lom sak 3 sticky rice19 Pi311 731939 1857723 Sian Deenoo Nam Ko Lom sak 2 maize20 Pi211 731442 1855584 Sopa Chairote Nam Ko Lom sak 2 tobacco21 Pi621 730720 1856293 Na Wongthai Muang Mai Pattana Lom sak 4 mungbeen22 Pi621 730652 1856326 Long Gongsee Muang Mai Pattana Lom sak 6 sweet tamarind23 Pi311 731617 1857260 Buntuang Sungpeng Nam Ko Yai Lom sak 10 sticky rice24 Pi211 734509 1858539 Pung Bunta Muang Mai Pattana Lom sak 14 sticky rice25 Pi211 734191 1858548 Tongkid Klaipha Nam Ko Set Lom sak 3 sweet tamarind26 Pi311 734147 1858313 Loo Jumpa Nam Ko Set Lom sak 2 chilli27 Pi311 734076 1858251 Tongluan Klaipha Nam Ko Set Lom sak 12 sticky rice28 Pi311 734612 1858368 Buntun Noimee Nam Ko Set Lom sak 3 cauliflower29 Pi211 734776 1860975 Buntum Bunglai Nongpla Lom sak 5 sticky rice30 Pi811 734908 1860777 India Punjun Nongpla Lom sak 23 rice31 Pi211 733395 1860639 Kumphong Wawichai Nongpla Lom sak 3 maize32 Pi811 735100 1860690 Udom Wawichai Nongpla Lom sak 21 sticky rice33 Pi311 732412 1861003 Chit Tongyorm Nongpla Lom sak 2 cauliflower34 Pi621 731485 1858670 Pramaun Wanpeng Nam Ko Yai Lom sak 2 sweet tamarind35 Pi311 731907 1858413 Pichai Kornsarn Nam Ko Lom sak 9 sticky rice36 Pi411 733642 1857102 Ton Mata Nam Ko Khok Lom sak 4 sticky rice37 Pi411 733750 1856852 Mun Pongun Nam Ko Khok Lom sak 7 sticky rice38 Pi613 731556 1861799 Saung Kwantong Huai Laeng Lom kao 3 tobacco39 Pi613 731669 1861795 Jom Kaewkingthai Huai Laeng Lom kao 3 cauliflower40 Pi613 731752 1861685 Pratiab Srangruang Huai Laeng Lom kao 5 tobacco41 Pi811 734293 1861022 Heng Gasee Nongpla Lom sak 10 sticky rice42 Pi811 734438 1861067 Seng Piewtong Nongpla Lom sak 4 tobacco43 Pi811 734033 1860193 Manop Yodorn Nongpla Lom sak 2 tobacco44 Pi811 734571 1860482 Wasan Ladlao Nongpla Lom sak 7 sticky rice45 Pi611 732134 1860391 Somnorm Meekhok Huai Pun Lom sak 2 tobacco46 Pi611 732250 1860298 Sanub Kaewduangdee Huai Pun Lom sak 13 shrub47 Pi411 732425 1859350 Tu Soma Huai Pun Lom sak 14 sticky rice48 Pi411 733163 1856514 Kaew Kabkam Nam Ko Lom sak 8 sticky rice49 Pi411 733270 1856442 Supun Mabun Rong Chuak Lom sak 6 sticky rice50 Pi411 733050 1856920 Tongson Chookaew Rongchuak Lom sak 12 sticky rice51 Pi311 731811 1857507 Lord Sroita Nam Ko Lom sak 3 sticky rice52 Pi411 735451 1855427 Tuy Chumsai Nam Ko Kae Khrua Lom sak 5 rice53 Pi411 735128 1855724 Rundorn Poomyai Nam Ko Thai Lom sak 10 sticky rice

CO

MP

AR

ISO

N B

ET

WE

EN

CO

NV

EN

TIO

NA

L LA

ND

EV

ALU

AT

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AN

D A

ME

TH

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SE

D O

N F

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ME

RS

’ IN

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EN

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DG

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71

App

endi

x 5:

Far

mer

s soi

l cla

ssifi

catio

n

TX

rco

lor

fert

ility

crac

kco

mpa

ctco

nsis

tenc

ede

pth

othe

rs1

Pi2

11D

in N

eau

pon

Sai

scye

llow

ish

red

poor

yha

rdp

5D

in S

ais

red

poor

yha

rdlo

w w

ater

hol

ding

cap

acity

m6

Din

Sai

sre

dpo

orn

7D

in S

ais

red

poor

yha

rdru

noff,

low

per

mea

bilit

yp

8D

in N

eau

pon

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scbl

ack&

yello

w-

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rd ro

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10D

in R

uan

pon

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sl(w

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ome

grav

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brow

nm

oder

ate

m15

Din

Nea

u po

n S

aisc

( m

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sand

(upp

er))

blac

km

oder

ate

stru

ctur

eles

s <

50 c

mse

dim

ent o

n to

p so

ilm

20D

in N

eau

cre

ddis

h ye

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poor

hard

lack

of p

lant

nut

rient

root

rot

n24

Din

Sai

Len

sbl

ack

mod

erat

efri

able

nom

25D

in S

ais

red

mod

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eno

m29

Din

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-bl

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good

friab

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g31

Din

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ang

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poor

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n16

Pi3

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in N

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m

17D

in L

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aisa

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ayey

blac

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e?dr

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18D

in D

umsa

ndy

soil

or m

ore

sand

bl

ack

mod

erat

efri

able

sedi

men

t on

top

soil

nom

19D

in L

en p

on S

aicl

ayey

(<10

0 cm

.)re

ddis

h br

own

good

stru

ctur

eles

sno

g23

Din

Rua

n N

eau

pon

Sai

scl

gray

mod

erat

esa

lt lic

khi

gh w

ater

tabl

em

26D

in S

ais

-po

orsa

lt lic

kp

27D

in S

ai L

ens

(and

dus

ty)

red&

blac

km

oder

ate

salt

lick

high

wat

er

tabl

e,flo

odin

gm

28D

in D

um L

en

-br

own-

blac

kpo

orca

n no

t sto

re w

ater

non

33D

in D

umla

terit

e(<

2 m

.)bl

ack

mod

erat

eso

il er

osio

n

m35

Din

Sai

Len

s ( s

andy

ove

r cla

yey

) -

mod

erat

ese

dim

ent o

n to

p so

ilno

m51

Din

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Sai

scbl

ack

mod

erat

efri

able

sedi

men

t (to

p so

il) o

ver c

laye

ym

9P

i411

Din

Dum

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Sai

-bl

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good

yno

g12

Din

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orly

dra

ined

g

13D

in R

uan

pon

Nea

ucl

redd

ish

brow

nm

oder

ate

yse

dim

ent o

n to

p so

il, lo

w p

erm

eaili

tyw

ater

logg

ing

m

14D

in N

eau

cbl

ack

mod

erat

ese

dim

ent o

n to

p so

il, g

ood

wat

er

hold

ing

capa

city

root

pen

etra

te,fl

oodd

ing

m36

Din

Dum

sand

y ov

er c

laye

ybl

ack

poor

y

sedi

men

t on

top

soil

p37

Din

Dum

sand

y ov

er c

laye

yre

ddis

h br

own

poor

y

sedi

men

t on

top

soil

p47

Din

Dum

-bl

ack

good

friab

lefla

t ter

rain

g48

Din

Dum

-bl

ack

good

friab

lelo

wla

ndg

49D

in D

um p

on S

aisc

blac

km

oder

ate

friab

leno

m50

Din

Dum

pon

Sai

scbl

ack

good

friab

leno

g52

Din

Dum

-bl

ack

good

friab

leno

g53

Din

Dum

-bl

ack

mod

erat

ey

m45

Pi6

11D

in p

on L

ook

Ran

gsc

(with

som

e gr

avel

) -

poor

root

rot

n46

Din

pon

Loo

k R

ang

- -

poor

poor

soi

lla

ck o

f wat

er re

sevi

orn

S

oil p

robl

em

S_R

atin

gIN

_NO

MU

LSN

Soi

l pro

pert

ies

CO

MP

AR

ISO

N B

ET

WE

EN

CO

NV

EN

TIO

NA

L LA

ND

EV

ALU

AT

ION

AN

D A

ME

TH

OD

BA

SE

D O

N F

AR

ME

RS

’ IN

DIG

EN

OU

S K

NO

WLE

DG

E

72

Fa

rmer

s soi

l cla

ssifi

catio

n ( c

ont.)

TX

rco

lor

fert

ility

crac

kco

mpa

ctco

nsis

tenc

ede

pth

othe

rs38

Pi6

13D

in D

um p

on S

ai -

brow

nm

oder

ate

50-1

00 c

mno

m39

Din

Dum

-bl

ack

mod

erat

efri

able

nom

40D

in D

um -

blac

kgo

odfri

able

soil

eros

ion

myc

orhi

za, r

oot r

ot,

g11

Pi6

21D

inN

eau

c (w

ith s

oft r

ocko

n to

p)ye

llow

ish

red

mod

erat

ey

stru

ctur

eles

ssl

ope

m21

Din

Dum

-bl

ack

mod

erat

eha

rd50

-100

cm

nom

22D

in D

um -

blac

km

oder

ate

50-1

00 c

mno

m34

Din

Sai

pon

Luk

Ran

ggs

,late

rite(

< 2

m.)

whi

tepo

ory

n2

Pi7

11D

in D

um -

blac

kgo

odflo

odin

gg

3D

in R

uan

pon

Nea

ucl

blac

km

oder

ate

hard

flood

ing

m4

Din

Nea

u po

n S

aisc

blac

kpo

ory

low

per

mea

bilit

yp

30P

i811

Din

Dum

dust

ygr

aygo

odflo

oddi

ng

g32

Din

Dum

-bl

ack

good

yse

dim

ent o

n to

p so

ilflo

oddi

ng

g

41D

in D

um N

eau

cbl

ack

good

ypo

orly

sui

ted

for p

lant

tree

, lac

k of

wat

erg

42D

in D

um -

blac

km

oder

ate

friab

lela

ck o

f wat

er fo

r pad

dyno

m43

Din

Nea

uc

-po

ory

stic

ky ro

ot p

enet

rate

p44

Din

Nea

uc(

sand

y ov

er c

laye

y )

gray

mod

erat

ese

dim

ent o

n to

p so

ilflo

oddi

ng

m

S

oil p

robl

em

S_R

atin

gIN

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MU

LSN

Soi

l pro

pert

ies


73

Appendix 6: Land suitability assessment by farmers

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15� �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! �! � �! �! �� ! �! �! � �! �! � �! �! �! � �! �� ! �! �! � �! �! � �! �! �! � �! �� ! �! �! � �! �! � �! �! �! �! �! � �� ! �! �! � � �! � �! �! �! �! �! �� ! �! �! � � �! � �! �! �! � �! �� ! �! �! � �! �! � �! �! �! �! �! � �� ! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! � �! � �! �� ! �! �! � �! �! � �! �! �! � �! �� ! � �! � �! �! � �! �! �! � �! �� ! �! �! � �! �! � �! �! �! � �! �� ! �! � � �! �! � �! �! � �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! �! �! � � �� ! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! �! � �! �! �� ! �! �! � �! �! � �! � �! � �! �� ! �! �! � �! �! � �! �! � �! �! �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! � �! �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! �! �! � �! �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! � � �! �! �! � �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! �! � �! �! �� ! �! �! � �! �! � �! � �! � �! �� ! �! �! � �! �! � �! �! � �! �! �� ! �! �! � �! �! � �! �! � �! �! �� ! �! �! � �! �! � �! �! � �! �! �� ! �! � �! �! � �! �! � �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! � �! �! �! �� ! �! �! � �! �! � � � �! �! �! �� ! �! �! � �! �! � � � � �! �! �� ! �! �! � �! �! � �! �! � � �! �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! � �! � �! �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! � � �! �! �! �! �! �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! � �! �! � �! �! �! �! �! �� ! �! �! � �! �! � �! �! �! �! �! �� ! �! � � �! �! � �! �! �! �! �! �� ! �! � �! �! �! �! �! �

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IN_NO MUSuitability rating for LUT_NO


74

Appendix 7: Farmers crop yields of actual land use

Ric

e

Toba

cco(

Eda

m)

Toba

cco(

Bur

ley)

Mai

ze

Mun

gbea

n

Cor

iand

er

Cau

liflo

wer

Chi

lly

Bel

l Pep

er

Egg

pla

nt

Yar

d lo

ng b

ean

Sha

llot

Tam

arin

d

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IN_NO MU LUT_NO

Documents

Comparison between conventional land evaluation and a ... · management at intermediate to high levels and thus achieve high crop yields. By considering the strengths of both methods,