Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, 221005
*Corresponding author, (E-mail: hpa@banaras.ernet.in)
Treated sewage water (TSW) when used for irrigation is expected to carry a part of the micronutrient (heavy metal) load. In order to find out the micronutrients accumulation in TSW irrigated soils and vegetable crops, surface soil samples as well as vegetable samples were collected from locations using TSW for irrigation for the last seven years. The soils were analyzed for DTPA extractable Cu, Fe, Mn, Zn and the vegetable samples were analyzed for total contents of these metals. The TSW-irrigated soils contained 6.0–66.8, 8.4–84.4, 2.4–6.4 and 2.0–20.4 mg kg−1 Fe, Mn, Zn and Cu, respectively whereas adjoining surface soils irrigated only with tube well water contained 10.0–35.5, 22.4–45.2, 2.8–3.2 and 3.6–7.6 mg kg−1, respectively. The mean values showed slightly higher amount of the micronutrients in the TSW-irrigated soil. The TSW-irrigated vegetables contained relatively higher amounts of micronutrients than the TW-irrigated vegetables, wherein okra, cauliflower, radish and broad bean had higher amount of Zn, Fe, Cu and Mn, respectively in their edible parts. Only TSW- and TW-irrigated potato showed lower manganese levels than the critical deficiency limit.
Micronutrients, vegetables, TSW irrigation
