Forms of Phosphorus and Soil Acidity in Different Land Management Systems of Meghalaya

Abstract

Distribution pattern of different forms of phosphorus and acidity were studied in surface soil samples collected from important land management systems viz., Bun cultivation, Terrace cultivated Land and Natural forest on hill slopes of Ri-bhoi District, Meghalaya. Total, exchangeable and pH dependent acidities decreased after closed burning of plant biomass under Bun farming, maximum decrease (87%) being recorded in exchangeable acidity, but the values of acidities after two years of Bun cultivation were in the same range to their initial values. Soils under terrace land recorded the highest values of all kinds of acidity. Closed burning under bun cultivation resulted manifold increase in Ca-P and Saloid-P and 38.3 per cent increase in Fe-P while Ai-P decreased by more than 9 times. The dominant form of inorganic P were Fe-P, reductant soluble P and occluded-P (97%) and existed in the order of reductant soluble P> occluded P> Fe-P under various land use systems on sloppy lands.