| Summary: | High rainfall intensity causes erosion because energy of rainfall breaks
soil aggregates and flows into the lower places. The erosion may also occur due to
land management which is not accordance with its capacity, without considering
the environment condition.
The study was conducted in Kedung Bulus Watershed, in Kebumen
Regency, Central Java Province. The amount of erosion was predicted using
USLE (Universal Soil Loss Equation) and GIS (Geographical Information
System). Based on the method, several maps were used including soil type, land
use, slope, and rainfall erosivity maps. Those four maps were overlaid to obtain
erosion classes and its area affected. The prediction of erosion was compared with
sedimen taken from the outlet of the sub Watershed.
The result of the research in Kedung Bulus sub Watershed, indicated that
there were 803 land units. After classifying, the area was dominated by very light
class erosion (99,45%) and the rest was classified as a light class erosion. The
result of the validity test indicated that there was not significantly different
between the observed and predicted erosion using USLE. It was denoted by lower
value of tcalculate compared to ttable
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