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 TWENTY YEARS PREDICTION The interpolated mean EC values per landform and relief units are given in table 1. A similar trend as depicted in the measured values and the tenth year prediction is exhibited, where the highest values occur in the floodplain and new terraces and the lowest in the ridges in both zones. The only difference is that the values have now increased particularly for the root-zone, but not much for the transition zone. Instead some relief units have shown an insignificant decrease in the transition zone as compared to the previous decade. The estimated areas that would be affected in the twentieth year in total area are given in table 2. show the reclassified EC maps which were produced from interpolation of simulated values using universal kriging. The maps (figure1. )clearly indicate how potentially affected areas are distributed over the study area. From these maps it’s clear that the salinity distribution follows the same pattern as with the previous cases, with low salinity occurring along the south western part and progressively increases in the opposite direction resulting in highly saline areas occurring in the north eastern side. This pattern indicates the effect of physiographic condition to salinity as the major part of the south western side is dominated by ridges and the north eastern side by the flood plains and lateral vales as well as terraces. This kind of pattern can also be associated with land use types as the latter side is dominated by paddy rice while south western side mainly cassava and maize are produced. Table 1 : Area per severity levels over entire area of interest Zone Total are (ha) Percentage area per salinity level Low Salinity Moderate High Salinity Severe Salinity ECe (dS/m) 0 - 4 4 - 8 8 - 16 > 16 Root -zone 22725 6.74 32.36 43.37 17.53 Transition zone 4.21 59.58 36.21 0.00 Table 2 : Area percentages per severity levels for transition zone Relief Unit Total are (ha) Percentage area per salinity level Low Salinity Moderate High Salinity Severe Salinity ECe (dS/m) 0 - 4 4 - 8 8 - 16 > 16 Floodplain 74450 0.00 8.19 88.68 3.12 Glacis 2106.75 1.66 41.51 56.62 0.21 Lateral Vale 3254.50 0.02 11.45 88.04 0.49 New Terraces 119.00 0.00 3.78 87.61 8.61 Old Terraces 556.75 0.85 62.24 36.24 0.67 Ridge 12994.50 6.04 72.56 21.35 0.05 Vale 2120.25 5.99 75.62 17.98 0.41 Figure 1 : Reclassified maps for root zone for the twenty years prediction Development of Methodologies for Land Degradation Assessment Applied to Land Use Planning in Thailand ^go to top