Sistem Usahatani Berkelanjutan Berbasis Dinamika Unsur Hara Pada Lahan Kering Masam

Abstract

. Based on its wide and spread, acid dry land has a higher potential as food crops resources, but unsuitability condition of soil physical and chemical properties with crops requirement need the specific technology to provide the optimum crop yields. The soil physical properties are high compactness (BD >1.2 gr cm-3), low of water holding capacity, bed permeabilitiy, and rate of soil eorison and ruhoff is high. The soil chemical properties are low of organic matter content, nutrients content, cation exchange capacity, and base saturation, while concentration of iron and aluminum oxides are higher concentration. On this condition, mix cropping can be an alternative sustainable farming system through improvement of physical and chemical properties. Improvement of physical properties including BD, porosity, and field capacity on mix cropping of cassava + maize + peanut were around 2.18 g cm-3; 49.12%; dan 37.99%; while on monoculture around 2.59 g cm-3; 42.35%; and 28.24%. Carbon and nitrogen balance on the mix cropping farming system were around +1.5 t ha-1 year-1 and + 10 kg ha-1 year-1, while on monoculture around -7.0 t ha-1 year-1 and -60 kg ha-1 year-1. Alley cropping is another one of sustainable alternative farming system through improvement of physical and chemical properties such as increasing of water holding capacity to accelerate nutrients dynamic into root surface areas by mass flow and diffusion processes, soil organic matter, and as sources of plat nutrients. Improvement of soil physical including BD, total porous, drainage porous, and available wateron alley cropping were around 1.08 g cm-3;, 59.2%; 25.6%; dan 14.6%; while on non alley cropping system around 1.28 g cm-3; 51.7%; 13.7%; dan 11.3%. Carbon and nitrogen content on alley cropping were around 2.73 and 0.20%, while on non alley cropping system around 1.31 dan 0.07%. The upland rice, peanut, and mung bean yields on alley cropping system were around 12.8, 11.3, and 5.3 ku ha-1; while on non alley cropping system around 7.7, 7.8, and 2.9 ku ha-1