Vertical distribution of micronutrients and heavy metals

Abstract

The present investigation was carried out on “Vertical distribution of micronutrients and heavy metals under sewage irrigated areas” at three different villages namely, Kalupur, Basantpur and Mathurapur of Nathnagar block in Bhagalpur district. For detailed study, total nine pedon were selected for the study of micronutrients and heavy metals (As, Cd and Pb) from sewage irrigated soils. Sewage-irrigation has received much attention due to enrichment of heavy metals in soils which impacts human health and social problems; however, use of sewage water in agricultural has been an age-old practice and can contribute to a reduction in stress on the utilizable water resource, which will not only reduce disposal problems of sewage water but also contribute towards improvement of soil fertility as it contains appreciable amounts of macro and micronutrients. These metals are associated with various soil components in different ways and these associations influence both their mobility and distribution in the soil profile. The DTPA-extractable soil micronutrients i.e., DTPA-Fe, Mn, Zn and Cu content varied from 8.23 to 19.22, 6.74 to 10.77, 0.41 to 2.48 and 0.05 to 1.27 mg kg-1 respectively in Kalupur village. Similarly in Basantpur village, DTPA-Fe, Mn, Zn and Cu content varied from 8.23 to 18.79 mg kg-1, 5.43 to 10.77 mg kg-1, 0.41 to 2.32 mg kg-1 and 0.01 to 0.91 mg kg-1, respectively. Whereas, DTPA-Fe, Mn, Zn and Cu content varied from 10.70 to 18.25 mg kg-1, 4.74 to 12.05 mg kg-1, 1.24 to 2.48 mg kg-1 and 1.06 to 4.32 mg kg-1, respectively in Mathurapur village. In Kalupur village, the value of DTPA-Cd, Pb and As in surface soils of sewage irrigated region varied from 0.08 to 0.48 mg kg-1, 0.37 to 6.35 mg kg-1 and 0.11 to 0.55 mg kg-1 Similarly, in Basantpur village it was observed that the range varied from 0.09 to 1.41 mg kg-1, 1.50 to 6.83 mg kg-1, and 0.17 to 0.68 mg kg-1 whereas in Mathurapur village the range varied from 0.08 to 2.55 mg kg-1, 1.92 to 6.35 mg kg-1 and 0.11 to 0.37 mg kg-1. The range of heavy metal (As, Cd and Pb) concentration in Kalupur village varied from 0.10 to 0.46 mg kg-1, 0.03 to 0.47 mg kg-1 and 0.37 to 04.32 mg kg-1 whereas, in Basantpur village varied from 0.10 to 0.48 mg kg-1, 0.05 to 0.96 mg kg-1, 1.04 to 4.65 mg kg-1 and in Mathurapur village varied from 0.107 to 0.551 mg kg-1, 0.05 to 1.73 mg kg-1and 1.06 to 4.32 mg kg-1.