Kinetic release behavior of DTPA-extractable manganese in soils of different cropping systems and total manganese content associated with soil texture

Abstract

In coarse textured alkaline soils of India, manganese deficiency is a emerging in some crops. Understanding the releasing pattern of manganese in soil under different cropping systems and distribution of total manganese content with different soil textures, a field survey and laboratory experiment were conducted in the Department of Soil Science, CCS HAU, Hisar. Results showed that DTPA-manganese content release in different cropping systems varies from soil to soil as well as system to system. In paddy-wheat cropping system the releasing of manganese was up to 40 days and thereafter the release of manganese appear remain constant and in cotton-wheat, sugarcane-sugarcane cropping systems it was up to 50 days, whereas in pearl millet-wheat, pearl millet-mustard and fallow-mustard cropping system, the releasing of manganese was up to 30 days and thereafter the manganese release remain constant in the leachate. Maximum manganese releasing was found up to 10 days and thereafter it gradually decreased in the leachate with increased in incubation interval. Magnitude of inherent release of manganese is governed by many factors, i.e. type and amount of clay, manganese status, alternate wet and dry cycles, pH, moisture content etc. However, manganese associated with different soil textures were found in the order: Silt > Clay > Sand (52.8 > 32.3 > 14.9%) of total soil manganese, respectively. Among all cropping systems, silt and clay particles showed greater affinity towards manganese adsorption may be due to their high surface areas and nutrient retention capacity.