Abstract
A GIS database was developed to evaluate land and water resources in a rainfed agricultural area in northeast Thailand using high resolution satellite data. In a small watershed, buffer analysis on the layout of a small-scale on-farm pond in paddy field area own by farming households was performed. By quantifying the pond capacity and the distribution degree, the potential water availability concerning the relationship between pond and paddy field layout was examined. Indices for evaluating the pond distribution (Dp) and the capacity (Cp) were proposed; these indices were integrated as water use availability (Awu). The methodologies were applied to 10 farming households in the small watershed. The result shows that there is enough room for the improvement of water use availability by arranging ponds or ensuring greater pond capacity. The active usage of ponds was recognized among farming households for which the ponds had high availability.
