The Study of Soil Physics and Chemical Character on Various Straightened Composition of Crop on Sub DAS Solo Hulu

This research was conducted in Sub DAS Solo Hulu area from October 2006 ? February 2007. The aim of this research was to study the effect of various straightened composition of crop to soil physics and chemical properties. The change will be seen when the available vegetation was more dominant than vegetation on the same area. This research used variable approach by survey in spacious and is supported by analysis in laboratory. T‐test and Correlation test was used in this research. The result of this research showed that according to vegetation survey, there was get six straightened composition of crop. The most of straightened composition of crop was predominated by Jati (Tectona grandis L.). Straightened composition of crop which predominated by Jati (Tectona grandis L.) giving effect of very real to some soil physics (soil pore, soil aggregate, field capacity) and chemical properties (pH H2O, pH KCl, organic matter, cation exchangeable capacity, total N, available P, available K and basalt spacing) at this same of soil type (Entisols and Alfisols). The various straightened composition of crop to effect soil physics and chemical properties through organic materials which yielded by litter material and crop activity of root. Various straightened composition of crop was predominated by annual crop will yield as litter material which is more compared to with straightened composition of predominated by season crop. Because annual crop have longer life cycle from at season crop so that can render as litter material as continually. Organic materials decomposition will yield organic acids as one of the source of organic materials of ground. While activity of root will render organic materials in ground through flaking back part of root of organic compound. Annual crop have root system ride, where its root hair can reach broader place so that organic compound which given into ground also progressively increase.