Potential screening of photoremediating crops and performance of maize in photoremediated coal mined acid soil with phosphorus application

Abstract

Aim: To assess the ability of phosphorus to counteract harmful effects of heavy metals by reducing their concentration and increasing the maize yield. Methodology: Bulk surface soil sample (0-15 cm) was collected from heavy metal polluted soil of coal mine areas of Sutnga. Two pot experiments were conducted. Ten kg capacity pots were laid out for three phytoremediating crop and replicated 33 times. The processed soil was used for filling the pots. The first pot experiment was conducted to assess the phytoremediation efficiency of Helianthus annus and Vigna ungniculata on heavy metal polluted soil. Thereafter in the second pot experiment Zea mays L. was planted in pots maintained under experiment 1 and subsequently eleven levels of phosphorus i.e. 0, 10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 mg P kg-1 soil were super imposed in non-phytoremediated soil, phytoremediated soils through SSP. The elemental uptake and concentration of available phosphorus and heavy metal was determined.? Results: From the first pot culture experiment, it was observed that heavy metals content in soil after harvesting of phytoremediating crops reduced significantly in both the phytoremediated soils as compared to non-phytoremediated soil. From the second pot experiment it was observed that phosphorus as well as the heavy metals concentration and uptake in maize decreased significantly with increasing doses of phosphorus added in non phytoremediated soil.? Interpretation: This study clearly indicates that sunflower can be successfully grown as a phytoremediating crop in coal mine affected soils of Jaintia hills for phytoremediation of heavy metal polluted soils.