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continuous event hydrology model developed to predict the impact of land management practice on water, sediment, and agricultural chemical yield in large,
complex watershed with varying soils, landuse, and management condition over long period of time.
1.2 Problems Statement
Population growth and increasing economic condition have pushed the increased of agriculture productions with intensive agricultural and land expansion
even in unsuitable area. The agricultural system is focused on economic benefit, without considering environmental aspect. We can easily find location of a field in
steep slope areas having plantation pattern direction exactly the same as the direction of steepness. This condition will increase water discharge.
Landcover in upper cimanuk catchment area has changed; the most changes are conversion to settlement areas. During 1991-2002, about 131.2 Ha of plantation
have been converted to settlement area from paddy fields to settlement area about 323.9 Ha, while that of un-irrigated agriculture to settlement about 91.9 Ha. The
converted areas became wider in 2005, whereas plantation was 169 Ha, paddy field was 258.9 Ha and agricultural area was 274.4 Ha. Forest and paddy field areas
relatively decrease in Upper Cimanuk Catchment area Daruati, 2008. Landuse and land-cover may have four major direct impacts on hydrological cycle and water
quality. The changes can cause floods, droughts and they can affect water quality Roger, 1994 in Weng, 2001. The process of urbanization has a considerable
hydrological impact in terms of influencing the nature of runoff and other hydrological characteristics, pollutant transport to river, and rate of erosion Goudie,
1990 in Weng, 2001. Nugroho 2006 in Runtunuwu 2007 was considering the upstream, middle,
and downstream section on several main rivers in Java Island. The study analyzed available discharge data from 1973 to 2003. Upper Cimanuk River has been
classified as having high decrease of flow pattern.
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1.3 Research Objectives
The major objective of the research is to develop SWAT and GIS model to investigate impact of landcover change to water discharge in Upper Cimanuk
Catchment Area. The specific objectives are:
To create hydrological respond unit HRU and water availability To use SWAT and GIS for determining the impact of landuse change to water
yield. To use model simulation to find optimum landuse that ensures the availability of
water.
1.4 Research Question
