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 SURFACE RUNOFF   Soil erosion by water is closely related to rainfall and runoff. In general terms, it can be defined as the detachment and transport of soil particles from one area to another by rainfall and running water respectively (White, 1997). In most cases, intense runoff is also capable of detaching soil particles making surface runoff a major causal factor in the process (Schwab et al., 1981). Erosion is a natural process but only when it takes place without the pressures of land use/ cover changes which hasten, the rate at which it occurs. Alterations in land use/ cover particularly affect the physical properties of soils which are closely related to infiltration characteristics. This in turn influences the runoff pattern in a catchment. An increase in the volume of runoff generated subsequently affects the amount of soil that is eroded. The consequences of changes in land use/cover on the rate of erosion can be assessed indirectly by studying runoff and its distribution in a catchment. In order to achieve this, it is necessary to quantify the volume of runoff taking these changes into account (DeRoo et al., 2000; Dingman, 2002; Green et al., 2000; Rientjes, 2004). This research had done by Solomon, H. (2005), the objective was to quantify the rate of runoff in the Nam Chun watershed taking into account the effects of different land use/ cover types. References White, R.E., 1997. Principles and practice of soil science : the soil as a natural resouces. Blackwell Science, Oxford, 348 pp. DeRoo, A.P.J., Wesseling, C.G. and Deursen, W.P.A.V., 2000. Physically based river basin modelling within a GIS: the LISFLOOD model. HYDROLOGICAL PROCESSES, 14(11-12): 1981-1992. Dingman, S.L., 2002. Physical hydrology. Prentice Hall, Upper Saddle River, 646 pp. Green, C.H., Parker, D.J. and Tunstall, S.M., 2000. Assessment of Flood Control and Management Options,Thematic Review IV.4 prepared as an input to the World Commission on Dams, CapeTown. www.dams.org Schwab, G.O., Frevert, R.K., Edminster, T.W. and K.K.Barnes, 1981. Soil and water conservation engineering. Wiley & Sons, New York etc., 525 pp. Solomon, H., 2005. GIS based surface runoff modelling and analysis of contributing factors: a case study of the Nam Chun Watershed, Thailand. MSc. Thesis, International Institute for Geo-Information Science and Earth Observation (ITC), Enschede, 99 pp. Schwab, G.O., Frevert, R.K., Edminster, T.W. and K.K.Barnes, 1981. Soil and water conservation engineering. Wiley & Sons, New York etc., 525 pp. Development of Methodologies for Land Degradation Assessment Applied to Land Use Planning in Thailand ^go to top