Soil Characteristics and Management Effects on Phosphorus Sorption by Highland Plateau Soils of Ethiopia

摘要: Differences in crop and fertilizer management are known to influence P retention by soils. An experiment was conducted study the effect of soil characteristics practices on sorptoin behavior highland plateau soils Ethiopia. Surface samples from two Vertisols, an Andisol, Alfisol were collected farmers' fields, research station farms, non-cultivated-non-fertilized areas. Phosphorus sorption data obtained equilibrating 3-g 30 mL 0.01 M CaCl 2 containing various amounts KH PO 4 . Inorganic fractions determined Hedley fractionation scheme. There little variation among Vertisol alluvial origin as a result cultivation-fertilization practices. For volcanic (Vertisol2 Andisols), Alfisol, fields sorbed more than non-cultivated samples. Least applied Andisol reflect relatively large resin extractable initially present these demonstrate that labile can subsequent sorption. Stepwise regression analysis showed accounts for 81% at 0.2 mg L -1 solution. The highest amount mainly due practice continuous cropping with minimal fertilization, which depletes P, therefore requires higher levels fertilization optimum yield.