Abstract
We were defined a major change in land use and assessed consequent environmental impact in Songkhla lake basin, southern part of Thailand using remote sensing techniques for geographic information system applications. 35 percent of forest area in the basin was disappeared during 1982 to 1996, contributing to 22 and 76 percent increas in rubber and aquaculture areaes respectively. Consequently, the basin was deteriorated by soil erosion. It was estimated that the average rate of soil loss increased from 4.91 ha-1 y_, in 1982 to 7.21 ha-1 y_1 in 1996. The rate of soil loss was found higher in greater slope or rubber area. The destruction of forest cover disturbed hydrological function in the basin, caused soil erosion and increased sediment in Songkhla lake system.
