Watershed Classification with GIS as an Instrument of Conflict Management in Tropical Highlands of the Lower Mekong Basin

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1 Page 1 of 8 Watershed Classification with GIS as an Instrument of Conflict Management in Tropical Highlands of the Lower Mekong Basin Project Abstract The University of Giessen is actually planning a research project about Watershed Management in the Tropical Highlands of the Lower Mekong Basin. Research focus is supposed to be the analysis of of Landuse Conflicts in Watershed Areas, different approaches of Watershed Management in general and especially the application of new technologies in this context. The main project objective is the development of a data base concept and operation framework which can be taken within certain limits - as a 'turnkey' package for mountain watersheds in SE-Asia. Dipl. Geogr. Christine Knie Senckenbergstr. 1, D Giessen Tel: Fax: christine.knie@geo.uni-giessen.de Problem Background The watersheds of SE-Asia s mountain regions are characterised by the permanent conflict between the need for conservation of natural resources on one hand and constantly growing population and land use pressure on the other hand. The increasing deforestation and forest degradation have direct impacts on the entire ecological infrastructure, on the hydrological and soil resources and on the local climate. Past experience has proved that environmental protection and conservation concepts can only be successful if socio-cultural and economic aspects are given equal weight to ecological considerations. The mountain areas of SE-Asia are not only an ecologically fragile regional ecosystem but, at the same time, they form the conflict-prone frontier between the traditional home of various hill tribes which are characterised by a great variety of ethno-specific land use systems - and the fastexpanding population of the lowland areas. And as further complicating the situation, also the (governmental) forest administrations pursue their own particular interests in the mountain areas. These typical problems are not country- but rather region-specific for tropical mountain areas. For example in Thailand the process of deforestation and watershed degradation and the resulting land use conflicts has progressed particularly far, but exactly the same trends can be observed in Thailand s neighbour countries Laos, Vietnam, Myanmar and even in Southern China as well. Modern technologies and in particular state-of-the-art Geographical Information Systems are offering the potential for efficient compilation and evaluation of already existing data material in order to identify generally valid, location-independent problem solving. strategies. It is believed that the project can supply a regionspecific conflict management framework which will be generally applicable in SE-Asia s tropical mountain areas. Hence, such a framework would be of general value for all technical cooperation projects dealing with land use, forestry, regional planning or natural resource management aspects in the entire region. Expected Results Data are compiled electronically, prepared and integrated. Comprehensive data compilation is finalised. A Geographical Information System (GIS) is installed. The information is prepared, converted from analogous to digital format (if necessary) and integrated into the digital data base. The information from existing maps is complemented by data extracted through multi-temporal

2 Page 2 of 8 analyses of suitable satellite images and aerial photos. The required attribute data are integrated into the GIS by means of a task- and project-adapted relational database. An Information System is established. The ecological- and socio-cultural development and the conflict potential of selected study areas is analysed and assessed with regard to its land capability and its development potential with the purpose of natural resource management. Potential land use conflicts are illustrated by means of various exemplary land use scenarios. An improved classification framework has been elaborated. The 'new' classification system has been tested on its practical feasibility. The transferability and user friendliness of the new information system has been carefully checked and optimised. A digital 'atlas' of a pilot area is established. The following thematic layers are established in the GIS-database: -base map information about settlements, roads, administrative boundaries, drainage network, watershed and sub-watershed boundaries - the ecological, socio-economical and socio-cultural development - land capability and watershed conservation classification as well as selected land use scenarios Presentation of the results The entire data compilation and processing is documented and recommendations for future data compilation activities are elaborated. The study results are presented at various decision maker levels. Based on these results training packages are prepared and tested. Application Relevance and Application Potential Traditional approaches have seen watershed management primarily as a physiogeographical and ecological problem. In contrast to this 'traditional' perspective, the proposed project demonstrating a more interdisciplinary approach which takes into account not only ecological but also socio-cultural and economic factors. The advantage of such a 'broader' approach is a much more comprehensive information foundation for the development of conservation concepts for the natural resources. The integrated consideration of ecological and socio-economical factors allows a more effective and more 'holistic' analysis and evaluation of the present land use pattern and land use systems, including their specific conflicts, potentials and risks. The GIS will be used to illustrate the mutual impacts and feedback processes of the various factors and the structure of conflicts which determine the watershed management. An important aim of the project will be to illustrate the potential of "sustainable information use". This term basically refers to a better exploitation the presently underutilised potential of already existing data by data integration and improved data exchange. A main objective and hence also a major justification of the proposed project is to compile results which are (largely) transferable to other, comparable watersheds elsewhere in the mountain areas of the whole project region. It is anticipated that the analysis process as well as the resulting evaluation and classification models developed for selected pilot areas will in principle be transferable to any other mountain watershed. For this reason the project will document in detail not only the actual study results but also the implementation of the various steps of the data compilation and data processing procedures. The final project objective is to establish a data base concept and operation framework which can be taken within certain limits - as a 'turnkey' package for any other mountain watershed in SE-Asia. Hence, the final documentation will be compiled in such a way that it can be used as a sort of 'watershed management manual'. Based on this manual, training packages can be established for specific aspects. Watershed Management Approaches in Tropical Highlands In the context of watershed management, the application of GIS/GPS/RS and [as well as] land use management is one of the research focuses of the GIS-Department at the Institute of Geography at the University of Giessen. In order to prevent (further) degradation of the natural resources of the tropical highlands of the lower Mekong Basin, a well-functional system of land use planning is required. During the last years new approaches for watershed management focused on the integration of new technologies like GIS/GPS/RS into management concepts. These new technologies by themselves cannot solve existing problems but they are certainly

3 Page 3 of 8 effective tools to compile, analyse and update land use planning relevant information. Topics of Research Approach Which kind of project approaches exist in the Lower Mekong Region? What exactly are their function for the region as a whole? Which problems occur? Which experiences were made with new technologies? How can we use these experiences to provide a watershed management framework which may possibly be generally applicable for other SE-Asian tropical mountain areas as well? How should data be analysed and stored in a way, that sensible, consistent, and decision-relevant information is produced. EXAMPLE: BASIC ANALYSIS OF WATERSHED CLASSIFICATION IN THAILAND Basic Analysis of the existing Watershed Classification of Thailand, established 1983, and of two new approaches which applicated modern technologies (Kasetsart University Bangkok 1990 and Cranfield University 1992) Key Questions: What is the aim of the classification? What are the essential basic data for watershed planning? Which data are actually available and how and from where can they be acquired? Which factors were taken into consideration and how are they compiled? Which criteria s have been used for the assignment of classes? Kasetsart University Bangkok 1983 Actual Watershed Classification Developed by National Environment Board of the Kasetsart University in Bangkok Thailand Aim of the Classification Prevention of Environmental Degradation Basic Data Topographical Map 1: (TM 50) 1967 Soil Map 1: Geology Map 1: Smallest Grid Size of Data Analysis: 1km² Factors Slope, Elevation Landform Data Processing Manual Analysis and Interpretation of Analogous Maps Statistical Factor Analysis

4 Page 4 of 8 Soil, Geology Comments Classification takes only ecological factors into account Socio-economical factors as for example water availability, infrastructure and location of villages were not analysed Pure manual analysis Very broad scale of basic data Outdated material (TM 50, 1967) Smallest grid size 1km² Class applications base on slope and elevation ranges analysed by visual interpretation of contour lines of TM 50 Classes Classification Scheme Class 1 Class 1A Permanent Class 1B Permanent Forest with already cleared areas Class 2 very high elevation and very steep slopes very high elevation and very steep slopes very high elevation and very steep slopes high elevation and steep up to very steep slopes Protected or conservation forest and headwater source Protection Should be reforested or maintain in permanent agroforestry Commercial forest Class 3 uplands with steep slopes Fruit tree plantation Class 4 gentle slope areas Upland farming Class 5 gentle slopes, flat areas Lowland farming Factor Analysis Slope Source: Contourlines of the TM 50 Percentage of Slope was calculated for the steepest region per grid (1skm) Landform Source: Contourlines of the TM 50 Minimum values for areas with high relief energy, Maximum values for areas with stable landforms Elevation Source: Contourlines of the TM 50 Average Elevation was calculated and divided by ten to get the percentage (750m=75%) Soil Source: Soil Map 1: Minimum values for most erosive, low fertility and shallow soils

5 Page 5 of 8 Maximum values for most stable, deep and fertile soils Geology Source: Geology Map 1: Low values for geologic formations which cause erosive, low fertility and shallow soils Maximum values for geologic formations which cause stable, deep and fertile soils Forest Source: Aerial Photos - Actual - University Chiang Mai 1990 Geo-Ecological Mapping Project of the Chiang Mai University Maathuis B.H.P. (1990): The Watershed Classification Versus the Geo-Ecological Mapping Approach Aim of the Classification: Landuse Planning with Regard to Ecological and Economical Variables Basic Data Topographical Map 1: (TM 50) 1967, Landuse map of the department of land development (1989) Spot Pan 1987 Factors Slope, Elevation Water Availability, Infrastructure Location of Villages, Soil and Geology is not analysed Data Processing Updating Landuse Map by Map and Satellite Analysis with GIS Digital Terrain Model (DTM) Slope Values from DTM Final Analysis and Classification using Overlay- Functions of GIS Comments Proposed land use takes ecological as well as socio-economical factors into account (see table "factor analysis") Geology and soil maps were not analysed because it was not possible to get relevant information by the available maps with their broad scale Relatively high data actuality by updating outdated TM 50 and Land Use Map with Spot Pan (1987) Smallest grid size: 67 m² Classification classes base on slope and elevation ranges Slope Values were derived from DTM (elaborated with GIS) Classification Scheme Classes Proposed Land Use Class 6 >50% Slope Forest Class % Slope and m Elevation Coffee, tea and cattle farming

6 Page 6 of 8 Class % Slope and <800 m Elevation Fruit trees and cattle farming Class % Slope and <1600 m Elevation Food crops using conservation practices Class 2 <10% Slope and m Elevation Short growing rice, mixed with temperate food crops Class 1 <10% Slope and <800 m Elevation Rice mixed with food crops Factor Analysis Slope Source: Digital Terrain Model (DTM) based on 100 m contourlines of TM 50 4 Slope Classes ( 0-10; 10-25; 25-50; >50% Slope) Elevation Source: TM 50 3 Elevation Classes (<800; ; >1600m) Source: Land Use MAP 1: from Department of Land Development -updated by interpretation of Spot Pan Images- Water Availability Source: TM 50 high suitable perennial drainage: 0-500m medium suitable perennial drainage: m periodical drainage: 0-250m Location of Villages Source: TM 50 - Distance (of potential fields) from villages - -updated by interpretation of Spot Pan Images- high suitable: m medium suitable: m Infrastructure Source: TM 50 - Distance (of potential fields) from roads - -Updated by interpretation of Spot Pan Images- high suitable: distance from main road: m medium suitable: distance from main road: m and/or distance from tracks: m Cranfield University 1992 MSC-Thesis in Land Resource Management at Cranfield University (Silsoe College) Dr. H.Weyerhaeuser (1994): Revised land capability Classification for a Watershed in Northern Thailand Aim of the Classification Natural Resource Management - Land Capability Study Basic Data Topographical Map 1: (TM 50)

7 Page 7 of 8 (in order to support the environment as well as the people) Factors Slope, Elevation Water Availability Infrastructure, Location of villages Soil and Geology is not analysed Landuse Ma (Classified with Landsat TM Satellite Image, 1992) Data Processing Map and Satellite Analysis with RS/GIS Digital Elevation Model (DEM) Slope Values from DEM Data Overlays, Buffers, Various Scenarios of Potential Landuse, Final Analysis and Classifications with GIS Comments proposed land use takes ecological as well as socio-economical factors into account (see table "factor analysis") Geology and soil maps were not analysed because it was not possible to get relevant information by the available maps with their broad scale Satellite Image from Landsat TM (1992) was used for actual data base application of classes base on potential land capability slope values were derived from DEM Data Overlays, Buffers, and Various Scenarios of Potential Landuse by GIS Classification Scheme Classes Class 1 Conservation / Permanent Proposed Land Use Thinning and selective harvesting of hard and soft wood and minor forest products Promotion of tourism (soft tourism) Class 2 Low Potential Diversified reforestation and forest plantations on larger scale Village woodlots for construction timber on smaller scale Permanent agroforestry, Fruit trees and Orchards, Promotion of tourism (soft tourism) Class 3 Moderate Potential Forest plantations of soft wood with shorter rotation, Fruit trees, Flower and Mushroom production, Agroforestry (coffee, tea, miang), Cut and carry for livestock Maintain: permanent ground cover Class 4 High Potential Vegetables, Maize, Sugar Cane, Cassava, Tobacco,

8 Page 8 of 8 Soybean, Potatoes, Beans, Strawberries, etc. Main objective: maintenance of permanent ground cover Class 5 Highest Potential Rice paddy and vegetables for cash crops Intensive cultivation Factor Analysis Slope Source: Two different Slope Maps derived from Digital Elevation Model (DEM) (Contour lines: 100 elevation points per sqkm from TM50 were digitised and SPANS was used for processing) Slope Map1-5 Classes: 0-10; 11-25; 26-50; ; >100% Slope Map2-5 Classes: 0-10; 11-20; 21-45; ; >100% Elevation Source: Elevation Map derived from DEM (similar procedure as for slope maps) 4 Classes: ; ; ; > 1200m Source: TM 50 and actual Land Use Map Water Water Availability Source: TM 50 and actual Land Use Map / 2 Buffer Zones: 300; 500m Infrastructure Distance from roads and tracks Source: TM 50 and actual Land Use Map 4 Buffer Zones: 0-0,5; 0,5-1; 1-1,5; 1,5-2,5 km Location of Villages Distance to the (potential) fields Source: TM 50, actual Land Use Map 4 Buffer Zones: 0,5; 1,5; 2,5; 5 km