ANALISIS DAMPAK PERUBAHAN PENGGUNAAN LAHAN TERHADAP DEGRADASI LAHAN DAN PENDAPATAN PETANI DI DAS WANGGU SULAWESI TENGGARA - La Ode Alwi; Sitti Marwah (Jurnal Pengkajian dan Pengembangan Teknologi Pertanian, 2015)
ABSTRACT Impact Analysis on The Change of Land Utilization toward Land Degradation and Farmers’ Income in Wanggu Watershed of South East Sulawesi. Objectives of the study were: (1) to assess the impact of the changes of land use in Wanggu watershed toward erosion, land degradation, ratio discharge (Qmax / Qmin), and farmer incomes; (2) to analyze land utilization and agro-technological model to improve soil infiltration capacity and water availability as well as to reduce the ratio discharge (Qmax / Qmin), the rate of erosion and land degradation; and (3) to formulate land-use and agrotechnological planning in sustainable watershed management. The research was conducted in July 2013-December 2013. The assessment on land degradation and watershed hydrological conditions of Wanggu was based on the data of land use changes, soil physical, erosion, run off coefficient, and river discharge. This study used survey methods and experimental plots to collect the data. Data on biophysical land including: climate, topography, soil type and land use derived from the results of the previous studies. The farmer’s income was calculated based on total production, total revenue and total cost. The results showed that the changes of land use caused land degradation, which might occur on: (i) upland agriculture, bushes, human settlements with the erosion > ETol with 36.3>21.0; 21.4>14.9 and 19.5>18 t/ha/yr and its slopes >8%, (ii) the ratio of river discharge (Qmax/Qmin> 30), land productivity and farmers' income (around IDR11.500.000/ha/th in upland, while in agroforestry about IDR21.500.000/ha/year < the standard of living allowance IDR22.000.000/year/hh). The land use and agrotechnological model from the scenario 5 could prevent land degradation, reduce the ratio of discharge (Qmax / Qmin <30), enhance soil productivity and increase income of farmers reaching for about IDR22.340.000–IDR25.730.000 ≥ IDR27.200.000/ha/year/hh. Those would meet the minimum requirement of living standard in South East Sulawesi.   Keywords: Land use, Wanggu Wathersed, impact, erosion, farming system ABSTRAKTujuan penelitan adalah (1) menganalisis dampak perubahan penggunaan lahan di DAS Wanggu Ds terhadap erosi, run off dan fluktuasi debit air, (2) mengkaji model penggunaan lahan dan agroteknologi yang mampu meningkatkan kapasitas infiltrasi tanah, menurunkan run off, fluktuasi debit air sungai dan laju erosi serta pendapatan petani, dan (3) merumuskan model perencanaan penggunaan lahan dan agrotekonologi yang tepat dalam pengelolaan DAS Wanggu berkelanjutan. Penelitian dilaksanakan pada bulan Juli 2013–Desember 2013. Degradasi lahan dan kondisi hidrologi DAS Wanggu dinilai berdasarkan terhadap perubahan penggunaan lahan, fisik tanah, erosi dan koefisien aliran permukaan serta debit sungai dengan menggunakan metode survei dan percobaan plot. Data biofisik lahan mencakup: data iklim, topografi, jenis tanah dan penggunaan lahan yang diperoleh dari hasil-hasil berbagai penelitian. Pendapatan petani dihitung berdasarkan pada produksi total, pendapatan dan biaya total yang dkeluarkan petani. Hasil studi menunjukkan bahwa perubahan penggunaan lahan yang tidak sesuai dengan kemampuan lahannya telah menyebabkan degradasi lahan umumnya pada: (i) pertanian lahan kering, semak-belukar, pemukiman dengan erosi > ETol secara berurutan 36,3 > 21,0; 21,4 >14,9 dan 19,5 >18 t/ha/th) pada kemiringan lereng > 8%, (ii) peningkatan Qmax/Qmin 36,8  > 30), (iii) produktivitas lahan dan pendatan petani adalah rendah (pertanian lahan kering Rp11.500.000/ha/th, dan kebun campuran/agroforestry Rp21.500.000/ha/th < standar kebutuhan hidup layak (KHL) Rp22.000.000/th/KK. Model penggunaan lahan dan agroteknologi Skenario 5 dapat mencegah degradasi lahan, menurunkan Qmax/Qmin 15,2 < 30), erosi < ETol (3,5–14,5 t/ha/th < 10,6–20,0 t/ha/th), meningkatkan produktivitas tanah dan pendapatan petani yang mencapai Rp22.340.000 – Rp25.730.000 ≥ Rp22.000.000/ha/th/KK yang memenuhi standar kebutuhan hidup layak di Sulawesi Tenggara. Kata kunci: Penggunaan lahan, DAS Wanggu, dampak, erosi, sistem pertanian