The Sinwulu River, located in the south-eastern flank of the Central
Range, is a major tributary of the Peinan River. The Sinwulu River is
35.4 km in length, and the catchment area is 639 km2 (Fig. 1B). In
relief, the Sinwulu catchment decreases toward the east, with a
maximum altitude of over 3000 m. The Sinwulu catchment has a
mean slope of 38° in the upstream area and 18° in the downstream
area. The mean elevation in the catchment is 1836 m; most of the
slope ranges from 30° to 50°.