Penggunaan Model Hidrologi di Sub DAS Ciliwung Hulu

A watershed has complex hydrological components and may be difficult to understand comprehensively. Modelling can be used to simplify and predict the processes which will happen. SWAT (Soil and Water Assessment Tool) is a model which can predict hydrology and simulate various processes in watershed.The objective of this research was: to analyse performance of SWAT model which predict discharge flow in upper Ciliwung watershed through calibration. Methods applied included analysis of the input data and calibration. The research was conducted in the period of June 2011 until June 2012. Based on the data of daily discharge flow in February and March 2008 and 2009, the calibration results showed values of R 0,80 and NSE 0,55. These results described that SWAT model can be used to predict hydrological processes in upper Ciliwung watershed.Prediction of hydrology could be used as the base to manage land agriculture towards sustainable agriculture

Improving Agricultural Resilience to Climate Change Through Soil Management

Climate change affects soil properties and hence crop growth. Several soil management practices potentially reduce vulnerability to unfavorable climate conditions. This paper reviews how climate change affects soil properties and how should soil management be tailored to increase adaptation capacity to extreme climatic conditions. The main symptoms of climate change such as the increase in the global atmospheric temperature, unpredictable onset of the wet and dry seasons and excessive or substantial decrease in rainfall are unfavorable conditions that affect crop growth and production. Several approaches, singly or a combination of two or more measures, can be selected to adapt to the climate change. These include conservation tillage, vegetative and engineering soil conservation, mulching, water harvesting, nutrient management, soil amelioration and soil biological management. Management of soil organic matter is very central in adapting to climate change because of its important role in improving water holding capacity, increasing soil infiltration capacity and soil percolation, buffering soil temperature, improving soil fertility and enhancing soil microbial activities. Organic matter management and other soil management and conservation practices discussed in this paper are relatively simple and have long been known, but often ignored. This paper reemphasizes the importance of those practices for sustaining agriculture amid the ever more serious effects of climate change on agriculture

Simulasi Manajemen Lahan di DAS Ciliwung Hulu Menggunakan Model Swat

INDONESIA Pengelolaan DAS merupakan masalah serius karena luas lahan kritis meningkat yang diakibatkan oleh pengelolaan lahan yang tidak sesuai dengan kesesuaian dan kemampuannya dan tidak disertai dengan USAha konservasi tanah dan air, serta Perubahan pola penggunaan lahan bervegetasi. Pengukuran lapang parameter yang berpengaruh terhadap hidrologi suatu DAS tidak mudah dilakukan karena karakteristik yang bersifat kompleks dan komprehensif. SWAT (Soil and Water Assessment Tool) merupakan suatu model yang dapat membantu dalam memperkirakan kondisi hidrologi berbasis proses fisik (physical based model). Penelitian ini bertujuan untuk untuk mengetahui nilai validasi aplikasi model SWAT di sub DAS Ciliwung Hulu dan menentukan Pengelolaan Lahan Terbaik (PLT) pada lahan pertanian di sub DAS Ciliwung Hulu. Metode yang digunakan meliputi pengumpulan data, pengolahan data input, penggunaan model SWAT, kalibrasi, validasi dan simulasi Pengelolaan Lahan Terbaik (PLT). Penelitian dilaksanakan dari bulan Juni 2011 sampai dengan Juni 2012. Validasi debit harian bulan Februari dan Maret tahun 2009 dan 2011 menunjukkan R 0,88 dan NSE 0,74. Nilai kalibrasi ini menunjukkan bahwa model SWAT dapat digunakan untuk memprediksi kondisi hidrologi pada sub DAS Ciliwung Hulu. Aplikasi teras bangku, penanaman menurut kontur, penanaman menurut strip dan agroforestri dapat menurunkan aliran permukaan. Teras bangku terbukti paling efektif menurunkan aliran permukaan hingga 79,21%.INGGRI