home    land degradation    project outcome    Gallery Flooding Flood Hazard Assessment Pilot Area • The Pilot Areas • Climate • Cover factor (C) estimation • Digital terrain analysis • Relationship between soil properties • Relationship of soil properties with different land use/cover types Methodology • Methodologies • LISEM Results • Result Soil Properties and Land Use • Runoff rate for different land cover types • Model calibration and validation • Sensitivity analysis • Land use scenarios • Rainfall size scenarios • Flooding Scenario - 2 years return period • Flooding Scenario - 10 years return period • Flooding Scenario - 20 years return period • Flooding Scenario - 50 years return period • Summary tables for each flood characteristic • Flood hazard mapping • Conclusions and Recommendation Erosion Erosion Assessment Pilot Area • The Pilot Areas • Climate • Cover factor (C) estimation • Digital terrain analysis • Relationship between soil properties • Relationship of soil properties with different land use/cover types Methodology • Methodologies • Erosion Models Result • Results • C-Factor Mapping for erosion assessment • Soil erosion assessment • Assessment of land use/cover change effect on soil erosion • Assessing critical zones for ephemeral gully formation • Erosion Assessment by Different Models • The recommended erosion models • RMMF Landslide Case I • Landslide hazard assessment • The area (Pilot 3) • Landslide Mapping in Wang Chin using digital image analysis Techniques. • Results • Discussions Case II • Doi Ang Khang (Ang Khang) (Pilot area 4) • Landslide mapping in Ang Khang using aerial photos • Landslide Inventory Mapping • Landslide modelling and Susceptibility mapping • Landslide Susceptibility Maps from the three Scenarios (models) • Comparison between Ang Khang and Wang Chin (with respect to weights of evidence modelling using morphometric parameters) Salinization Case I • Pilot area II • Soil salinity • Salinization • Geomorphology • Soils • Geopedologic map • Results Case II • CASE II - The study of Yadav, R.D. (2005), • Methodology • Crop Simulation Model • PS 123 • Results • Mathematical (Regression) Model for Crop Yield Estimation • Conclusion Case III • Case III • Modeling Salinization • Geostatistics and Interpolation (GIS and Kriging) • Model Simulation and Prediction of Salinity • Simulated Depth to water table • Tenth Years Prediction • Twenty Years Prediction • Conclusion Runoff • Surface Runoff • Methodology • Modelling Runoff • Modelling Runoff Using Empirical Approach • Modelling runoff using the Semi-physical approach • Estimation with the Curve Number Method • Results and Discussion • Generation of Scenarios • Comparison of runoff rates with soil loss map • Conclusions • Presentation of papers based on project work at international • Workshop in Lomsak • Hua Hin seminar • Training of LDD staff • GIS and RS based predictive soil mapping • Soil erosion assessment • Landslide hazard assessment • Flood hazard assessment • Soil salinity study • List of completed MSc. theses on project GEOMORPHOLOGY Geomorphology was studied by Aerial photo interpretation (API): The photo set contains eight aerial photographs, which cover approximately 300 Km2 (30,000 ha). The photos were organized in two photo-runs, and formulated six stereo-pairs were interpreted. The result shows that there are two major Landscapes namely: Valley, and Peneplain. Ten relief types, two lithological units (making use of the geological map and reliable literature), and finally fourteen landforms were distinguished (see figure 1). Statistics reveals that there are 77 delineations (at the level of landform). The minimum delineation is approximately six hectares, while the maximum size is approximately 3800 hectares. The interpretation was done over four transparencies, and joined manually using the ‘lighting table’. Table (1) shows the description of the geopedologic units and the hierarchal classification associated with them Figure 1 : Geopedological map Table 1 : Geopedologic legend Relief Type LIthology Landform GP Code Ridge Sedimentary rocks Korat Group Top complex Pe111 Side complex Pe112 Slope-facet complex Pe113 Summit Pe114 Tread riser complex Pe115 Glacis Sedimentary rocks Korat Group Tread riser complex Pe211 Vale Sedimentary rocks Korat Group Slope complex Pe311 Lateral Vale Sedimentary rocks Korat Group Side complex Pe411 Bottom-Side complex Pe412 Bottom complex Pe413 Depression Sedimentary rocks Korat Group Basin Pe511 Food plain Alluvial deposits Levee-overflow complex Va111 Old Terraces Alluvial deposits Overflow-Basin complex Va211 New Terraces Alluvial deposits Overflow-Basin complex Va311 Landcover The Land cover of Korat plateau was subject to a number of changes. The native Landcover in the area is ‘Dipterocarps’ forest. A major part of it has been changed to agriculture land and paddy fields as a consequence of the agriculture development, which begin in the sixties. Yamamoto et al. mentioned that the maize and kenaf was introduced to the local farmers in the 1960’s, the Cassava in the 1970’s,and then sugarcane in the 1980’s, while the dominant crops at the time of the fieldwork was the cassava, and sugarcane. The classified map clearly shows the pattern of crop growing areas. Light green areas are classified as rice, which is lowland where rice is grown. The extent of maize growing areas is less and not corresponding with ground truthing. The area at the time of ground truthing was maize might be covered by cassava in the image (accuracy percentage is 69% as observed from a confusion matrix). Since ground truthing time and the period the image was shortly differ, it is possible that landuse in a shifting cultivating system might have shifted from maize growing to cassava growing during the time of field work (see figure 2). Figure 2 : Landuse/cover map and feature space References LDD, Excursion program for the international symposium on paddy soils. 1996, LDD: Khon Kaen. Imaizumi, K., Sukchan, S., Wichaidit, P., Srisuk, K., and Kaneko,F., Hydrological and Geochemical behavior of saline groundwater im phra yun, northeast Thailand. 2002, LDD: Khon Kaen. p. 7-14. Pramojanee, P., A study of the relationship between salt affected soils and landforms in Amphoe Kam Sakae Saeng area, Nahkon Ratchasima province, Thailand, in soil science division. 1982, ITC: Enschede. p. 155. Development of Methodologies for Land Degradation Assessment Applied to Land Use Planning in Thailand ^go to top