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 ASSESSMENT OF LAND USE/COVER CHANGE EFFECT ON SOIL EROSION To study the effect of land use/cover change on soil erosion, trend of land use/cover change in periods 1988 to 2007 and the soil loss rates in different land use/cover in 2007 were analyzed. Assuming the estimated soil loss rates of 2007 as being standard erosion rates for different land use/cover types the amount of soil losses (tons/hectare y) was calculated for 1988 and 2000. Total soil loss estimated in the Namchun watershed was 29,070.06 (tons/hectare) in 1988 and 44,263.19 (tons/hectare) in 2000 Maximum total amount of soil loss occurred in 2007 with 61,684.70 (tons/hectare). Increasing erosion rates are caused by the transformation of natural forest areas (forest and degraded forest) turned into cultivation areas (agriculture and orchard). The expansion of agriculture areas took place on forest areas will increase the bulk density and decrease organic matter content. These evident could support the assumption of increasing amount of soil loss above. Both the results from land use/cover change on amount of soil loss per year and the distribution pattern of soil properties (bulk density and organic matter content) together with trend of land use/cover change were the important evident that lead to soil erosion. Table 1 : Amount of soil loss (t/y) in periods of 1988, 2000 and 2007 Land use/cover Soil loss rate (t/h/y) 1988 2000 2007 Area (Ha) Soil loss (t/y) Area (Ha) Soil loss (t/y) Area (Ha) Soil loss (t/y) F 0.99 2699 2672.01 1411 1396.89 857 848.43 DF 1.47 2663 3914.61 2551 3749.97 2267 3332.49 A 26.06 740 19284.40 1107 28848.42 1686 43937.16 G 5.39 496 2673.44 1081 5826.59 778 4193.42 O 8.76 60 525.60 507 4441.32 1070 9373.20 Total 6658 29070.06 6658 44263.19 6658 61684.70 Development of Methodologies for Land Degradation Assessment Applied to Land Use Planning in Thailand ^go to top