Analisis Perubahan Penggunaan Lahan dan Debit Aliran Sungai Ciwidey, Jawa Barat

Abstract

Population growth and rapid regional development in Ciwidey Watershed lead to very intensive land use changes that icrease flooding risk in the region. This study aimed to identify land use changes and its effects on river discharge in Ciwidey Watershed. Land use changes that occured during 1994 up to 2005 periode werw primary forest, secondary forest, industrial zones, mixed garden, dry land agriculture, plantations, settlements, and ricefield. Most of land use changes occurred in the period 1997 to 2001. During that period, the primary forests and secondary forests esperienced the largest change where respectively 742.3 ha and 471.1 ha were converted to other land uses. The maximum discharge are Ciwidey river in 1997 and 1998 were 27.0 m3/s and 33.1 m3/s with run coefficient of respectively 0.69 and 0.84 . The high runoff coefficient was allegedly associated with dominant land use changes that occurred in the periode of 1997 to 2001. There are other factors that might contribute to the high discharge and high magnitude of runoff coefficient, namely the impact of El Nino and La Nina which occurred in 1997 and 1998. El Nino causes drought season and La Nina causes long rainy season.