Application of Soil conservation Services (SCS) Model to Predict Surface Runoff in Oil Palm Plantation Afdeling III, Business Unit of rejosari, PTPN VII South of Lampung.

Abstract

Surface runoff or overland flow is the portion of rainfall which is not absorbed by the soil and is not accumulated on soil surface, but runs down-slope and collects in gullies and streams ( Hillel, 1997). Unproportionaly of surface runoff especially in rainy season can cause water loss quickly. Surface runoff volume can be predicted by using Soil Concervation Services (SCS) model. The objectives of this research is to predict surface runoff volume using Soil Conservation Services (SCS) model and to compare it with the measured ones. The research was carried out at Oil Palm Plantation of Afdeling III, Management Unit of Rejosari, PTPN VII South of Lampung. Main activities of the research consist of (a) identifications of hidrology soil grouph (HSG), (b) estimation of land cover and antecedent moisture condition (AMC), (c) delineation of microcatchment, (d) measurement of surface runoff in microcatchment outlet, and (e) predicting of surface runoff using SCS and PCRaster models. Soil Conservation Services (SCS) model can be used to predicted surface runoff. Model performance is quite well, which showed by determination coefficient and Root Mean Square Error (RMS-E) are 0.54 (R2) and 9.37 (RMS- E) respectively. Maximum surface runoff volume both measured (61.45 mm) and predicted (32.82 mm) were obtained on March 10th 2008 with rainfall 101.85 mm. While minimum value on April 4th 2006 with surface runoff volume measured, a predicted and rainfall were 0.08, 0.32 and 17.36 mm