Quantification and modelling of sediment loading in oil palm catchment

Abstract

A small and matured oil palm catchment of 15.62 ha in Ladang Sedenak, Johor was monitored to study the Suspended Solids (SS) loading and factors influencing the sedimentation rate. This study is designed to establish comprehensive understanding on hillslope erosion processes in oil palm plantation catchment. Ten storm events with a total of 133 samples were analyzed for SS concentration and turbidity. Rainfall and streamflow were recorded continuously. Baseflow samples were also analysed. SS concentration ranged between 2 and 2710 mg/L during storms but only from 3 to 6 mg/L during baseflow. Turbidity values range between 20.5 NTU and 2875 NTU. The relationships between SS concentration and turbidity for individual storm events are not consistent with coefficient of determination, r2 ranging from 0.37 to 0.96. The intercepts of the regression line range from -57.2 to 391.9 whereas the slopes from 0.44 to 1.66. Therefore, all event data are combined to minimise the variation. The new SS-turbidity relationship for the combined events is SS~0.813Tur+3.69 (r2~0.86, p