2.3. SWAT model preparation
SWAT databases of land use, topography, soil, climate, and
agricultural practice were imported. The land use distribution in
2009 was interpreted with Landsat image (Fig. 1). The paddy
field
was reclassified as paddy rice and the upland was reclassified as
soybeans. The agricultural practices of two dominant crops were
considered which included the planting and harvest date,