Soil characteristics and available micro-nutrient status in some acid saline soils of coastal agro-ecosystem in West Bengal.

摘要

Four representative soil profiles were selected from the village - Halapara, Block-Canning, District 24-Parganas (S), West Bengal under coastal agro-ecosystem to study the characteristics of soils and its available micro-nutrient status. The soils were silty clay loam to silty clay in texture, and acidic in reaction (pH_w-4.1 to 5.3). Soils of pedons 1 and 4 were saline in nature (EC-4.1 to 14.6 dSm-1). Cation exchange capacity ranged from 12.4 to 20.5 cmol(p+) kg-1 and the soils showed high content of organic carbon (7.3 to 11.9 g kg-1). Mg2+ was the dominant cation in the exchange complex followed by Ca2+, Na+ and K+. Available Fe, Mn, Cu and Zn (DTPA extractable) ranged from 66.0 to 234.8, 8.5 to 20.8, 0.9 to 6.9 and 0.3 to 2.7 ppm, respectively. Vertical distribution of micronutrients indicated that available Fe, Mn and Zn was high in the surface soils and gradually decreased in the lower horizons; however, no definite pattern was observed in case of available Cu. Significant negative correlations obtained for pH with available Fe, Cu and Zn indicated enhanced availability of these cations under low pH conditions. Organic carbon was also significantly and positively correlated with available Fe, Mn and Cu while clay content showed positive correlation with available Cu content of soils.