Application of GIS in monitoring the soil erosion in sloping agricultural lands : a case study in Uma Oya Watershed, Sri Lanka | |
| Author | Kokularamanan, Sathiyavaani |
| Call Number | AIT Thesis no.NR-05-10 |
| Subject(s) | Soil erosion--Sri Lanka Geographic information systems--Sri Lanka |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. NR-05-10 |
| Abstract | Soil erosion is a major environmental issue posing threat to sustainable agriculture. For effective erosion control, it is needed to estimate the soil loss to identify the key factors using an effective and accurate method. This research is an attempt to assessing the range of soil loss values for a typical watershed on mountainous area in Sri Lanka on the basis of Universal Soil Loss Equation with the application of Geographic Information Systems. Geo- referenced information is a prerequisite for land use management and Geographic Information System can provide means to inventoried resource data and model processes from the local to global scales. The raster and vector based GIS can be utilized for the spatial and temporal analysis of land use and soil erosion. The specific objective of the study were to monitor the soil erosion in terms of ranges of annual soil loss by integrating spatial and non spatial techniques, and suggest the measures to reduce the soil erosion for sustainable land use management to ensure the long-term productivity of land resources with minimum negative effect on the environment. The result shows the rate of soil erosion in the watershed is very high, for exceeding acceptable limits in most of the areas. The trend in four year period from 1998 to 2002 shows that the watershed condition is degrading with increase rate of erosion, a phenomenon which is primarily explained by degradation of forest and expansion of annual crop cultivation The study concludes that the high rate of soil erosion is mainly because of the annual crop cultivation on steep slope lands. It can be seen a relationship between the changes of population density and that of land uses, which are more related to erosion and a methodology should develop to correct these in details. It is also conclude that the ARC VIEW spatial analysts for the estimation of soil erosion seems to be very useful using of high resolution grid cell data along with the other factor in order to estimate soil loss. The use of GIS has been found to be very effective in analyzing soil erosion spatially by overlying various maps related to factors affecting soil erosion. ยท On the applicability of the USLE, the research concludes the soil loss values under steep slopes are not reliable enough. This implies for more research on developing appropriate approach for correctly assessing soil erosion rates in Uma Oya Watershed in Sri Lanka. However this method is very effective in finding the range of soil erosion rates at different areas and finally in developing the general watershed plan. |
| Year | 2005 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. NR-05-10 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Development and Sustainability (DDS) |
| Academic Program/FoS | Natural Resources Management (NRM) |
| Chairperson(s) | Shrestha, Rajendra Prasad; |
| Examination Committee(s) | Gautam, Ambika. P ;Ranamukhaarachchi, S. L. ;Lal Samarakoon; |
| Scholarship Donor(s) | Government of the Netherlands; |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2005 |