EFFECT OF LOGGING ON SEDIMENT YIELD IN A HILL DIPTEROCARP FOREST IN PENINSULAR MALAYSIA

Abstract

Investigations on suspended sediment yield were made from three small forested catchments before and after logging in Bukit Berembun Forest Reserve, Negeri Sembilan, Malaysia, over a period of six years from 1980. Both catchments (BC1 and BC3) were logged using normal 'san-tai-wong' method, but BC3 with close supervision and additional prescriptions, such as a proper road construction and alignment and construction of cross drains on steep logging roads. BC2 remained as control catchment. After logging, the suspended sediment yield increased by 97 and 70% from BC1 and BC3 respectively, as compared to before logging. The highest weighted suspended sediment concentration also increased from 386.0 to 844.5 mg/l from BC1 and 158.3 to 318.2 mg/i from BC3. Hence supervised logging could reduce sediment in forest waterways considerably.