Electronic Theses and Dissertation

Permasalahan yang paling menonjol di DAS Kluet adalah frekuensi banjir. Banjir yang terjadi di DAS Kluet disebebkan oleh sedimentasi di Sungai utama yang sangat besar. Hasil pengamatan secara visual memperlihatkan kondisi tutupan lahan di DAS Kluet yang relatif terjaga. Penelitian ini bertujuan untuk mengetahui nilai laju erosi lahan dan sebaran Tingkat Bahaya Erosi (TBE) DAS Kluet. Perhitungan erosi dilakukan menggunakan Metode Modified Universal Soil Loss Equation (MUSLE) berbasis Sistem Informasi Geografis (SIG). Metode MUSLE digunakan untuk melihat kecenderungan hubungan antara erosi lahan dengan potensi sedimentasi di Sungai. Dari hasil perhitungan diperoleh laju erosi lahan sebesar 8.391,46 ton/ha/tahun. Tingkat bahaya erosi DAS Kluet didominasi oleh kelas sangat ringan sebesar 89,43% dengan luas 2.653,91 km2, kemudian diikuti kelas ringan 3,13% dengan luas 92,92 km2, sedang 6,35% dengan luas 188,54 km2, berat 1,03% dengan luas 30,53 km2, dan sangat berat 0,06% dengan luas 1,65 km2. Persentase TBE sangat ringan terbesar terjadi pada tutupan lahan dengan kerapatan tajuk yang baik, tanah dengan erodibilitas rendah, serta kemiringan lereng yang landai. Sedangkan TBE sangat berat terjadi pada lahan dengan kecuraman tinggi dan lahan terbuka akibat dari tidak adanya vegetasi penutup lahan yang dapat menghambat limpasan dan pengangkutan partikel tanah. Hasil penelitian ini menunjukkan bahwa erosi lahan di DAS Kluet tidak berkontribusi secara signifikan terhadap sedimentasi di sungai Kluet.

The increasing frequency of flooding is the most significant problem on the Kluet River. The high rate of sedimentation in the Kluet River affects river morphology. This research aims to determine the value of the rate of land erosion and the distribution of the Erosion Hazard Level (EHL) of the Kluet watershed. In this research, erosion calculations were carried out using the Modified Universal Soil Loss Equation (MUSLE) method based on Geographic Information Systems (GIS). The MUSLE method is used to see the relationship between erosion and the potential for river sedimentation. The calculation results have shown that erosion using the MUSLE method in the Kluet watershed was 8.391,46 tonnes/ha/year. The erosion hazard level of the Kluet watershed has been dominated by the very light class at 89,43% with an area of 2.653,91 km2, followed by the light class at 3.13% with an area of 92,92 km2, and medium 6.35% for the area. amounting to 188.54 km2, heavy 1.03% with an area of 30.53 km2, and very heavy 0.06% with an area of 1.65 km2. The very low percentage of EHL is caused by land cover with good canopy density, soil with low levels of erosion, and gentle slopes. Meanwhile, EHL is very severe on land with high steepness and open land because there is no vegetation covering the land which can inhibit runoff and transport of soil particles. The results of this research indicate that land erosion in the Kluet watershed does not make a significant contribution to sedimentation in the Kluet River.