Status of zinc fractions in soils of Cooch Behar district, West Bengal, India

摘要

A study was conducted on the distribution of different forms of zinc (Zn) in soils (0-20 and 20-40 cm depths) in different blocks of Cooch Behar district, West Bengal, India. The soils of the selected areas were acidic in reaction (pH) at both the depths, ranging from 4.23 to 6.96 (0-20 cm) and 3.89 to 6.45 (20-40 cm) and having sandy to sandy loam texture. The different fractions of Zn varied among the soils of all locations. The order of different zinc fractions was: exchangeable zinc (Ex-Zn) organic matter-bound zinc (OM-Zn) manganese oxide-bound zinc (Mn-Ox-Zn) crystalline oxide-bound zinc (Cry-Ox-Zn) amorphous iron oxide-bound zinc (Am-Ox-Zn). Am-Ox-Zn was relatively higher in the soils of Mekhliganj, i. e. 1.56 kg ha(-1) at 0-20 cm depth and 0.92 kg ha(-1) in the soils of Tufanganj-II at 20-40 cm depth respectively. Exch-Zn, OM-Zn, Mn-Ox-Zn and Am-Ox-Zn were positively correlated with CEC (r = 0.088, r = 0.105, r = 0.137, r = 0.103) at 0-20 cm depth, while at 20-40 cm depth, Exch-Zn, OM-Zn, Mn-Ox-Zn, Am-Ox Zn and CryOx- Zn were positively correlated with CEC (r = 0.204, r = 0.168, r = 0.342, r = 0.123, r = 0.278). The influence of different soil properties on the distribution of Znfractions in the soils was apparent from this study.