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6 CHAPTER VI
CONCLUSION AND RECOMMENDATION
6.1 Conclusion
Conclusion are given based on the purposes and objectives of the study. The purposes of this study are to reduce soil erosion and to maintain water availaibility of non-
groundwater basin watershed. The conclusion for the objectives of this study are :
6.1.1 Land Characteristics of Non-Groundwater Basin in Buper Watershed
1. Buper Watershed rock layer below the soil layer are mafic and ultramafic layer which are impermeable, so that the water can only infiltrate through the soil layer.
On this thin soil clay, plant can grow according to the thickness of the soil. In savannah area, thin soil layer has a thickness around 3-25 cm, and only in the area
where sediments are concentrated, soil layer has a thickness aroud 40-60 cm. 2. In the area of non- groundwater basin, forest recovery is difficult when the land
have been eroded or have been exposed. This condition occurs because the soil clay where the plant grew was lost due to erosion.
3. Exposed surface expansion is occurs go toward upstream because the increasing erosion rate due to the slope of 25-40.
6.1.2 Water Balance in Buper Watershed
1. Dependable flow is 0,24 m3sec for 12.6 km2 area of Buper Watershed. Estimated water demand in 2011 is 0.28 m3sec, so it was insufficient for water demand..
2. The service areas are area with lower topography and distribution easiness .
These criterias selection are based on development and controlling capability for water
distribution facilities .
3. The service area are District of Heram and District of South Jayapura, which have population projection until 2016 of 139,496 people.
6.1.3 Erosion in Buper Watershed
1. The results of USLE showed that most of the Buper Watershed have very low erosion rate with a total area of 9,92 km
2
, low erosion area of 2,6 km
2
and moderate erosion area of 0,08 km
2
. The highest erosion in Buper Watersehed is 82,63 tonhectareyear and the lowest erosion in Buper Watershed is 1,71
tonhectareyear.
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2. Management strategies to reduce soil losess are build a medium structure of bench terrace for medium rate erosion and traditional bench terrace for low rate erosion.
6.1.4 Conservation Planning Of Non-Groundwater Basin Watershed
