Estimate ofErosionfor Land Conservation ofGarang Watershed
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ESTIMASI EROSI UNTUK PENENTUAN KONSERVASl TANAH DI DAS GARANG JAWA TENGAH MENGGUNAKAN FOTO UDARA Estimate of Erosionfor Land Conservation ofGarang Watershed Central Java Using Aerial Photographs Andriati Cahyaningsih1, Totok Gunawan2, Sudibyakto2 Program Studi Penginderaan Jauh Program Pasca Sarjana Universitas Gadjah Mada ABSTRACT The aim of this research is to find out the accuracy of aerial photographic interpretation to obtain land parameters, for estimating the erosion of Garang watershed conservation area. This research used aerial photographs of 1991 scaled at 1: 25.000 combined with topographic and other tematic maps, survey and secondary data to get some information erosion estimataen. The estimate of erosion used USLE method, take of into consideration the erosivity (R), soil erodibility (K), topographies factors (LS), crop, and practices (CP). The input variables was calculated and modeled in Geographical Information System (GIS). The result showed that the accuracy assesments of landform and land use interpretation are more than 91,24 % and 90,06 %. The erosion of Garang watershed 0 ton/hectares/year to 1598,85 ton/hectares/year. The erosion class I, class II, class III, and class IV is 9.041,78 ha, 3340,58 ha, 4.345,59 ha, and 681.17 ha respectively. Keywords : Interpretation - Erosion - Conservation PENGANTAR DAS Garang merupakan daerah yang sering mengalami banjir terutama di sekitar pertemuan tiga sungai besar, yaitu Sungai Garang, Sungai Kripik, dan Sungai Kreo. Erosi yang terjadi di bagian atas menjadi salah satu sumber sedimen yang masuk ke sungai .dan i Nitikan Baru UH11/161, Yogyakarta 55162 2Fakultas Geografi Universitas Gadajah Mada, Yogyakarta 271
Estimate ofErosionfor Land Conservation ofGarang Watershed
