Abstract
The soils under 6-year old plantations of seven Nitrogen Fixing Trees (NFTs) viz., Acacia nilotica, Acacia auriculiformis, Bauhinia variegata, Leucaena leucocephala, Albizia lebbeck, Acacia catechu and Dalbergia sissoo were studied to know the micronutrient (Zn, Cu, Fe and Mn) build up in soil at four different peripheral distances (30, 60, 90 and 120 cm from tree trunk) and two soil depths (0-15 and 15-30 cm). The concentration of these micronutrients were also estimated in leaves of the NFTs. Acacia nilotica leaves registered maximum concentration of Zn, Cu, Fe and a comparable content of Mn. In soils, available Zn, Cu, Fe and Mn were significantly higher under the NFTs at all peripheral distances as well as soil depths than controls (open plots adjacent to plantation plots). A declining trend in amount of available nutrients was observed towards greater peripheral distance and soil depth. Maximum build up of available Cu, Fe and Mn was noticed under Acacia nilotica whereas, maximum Zn was observed under Albizia lebbeck.
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