Feldspar mine spoil rehabilitation: Use of legumes and bio inoculants to establish soil fertility on agro-silviculture basis

In recent researches, legumes have been used to revegetate the mining areas with nitrogen-fixing species. The current study also used legumes to revive the fertility of feldspar mine spoil along with Azotobacter chrococcum, Azospirillum brasilense and Glomus mosseae (AMF) in various combinations with organic and inorganic nutrient supplements. All legumes Acacia nilotica, Acacia senegal, Prosopis cineraria, Cyamopsis tetragonoloba and Cassia angustifolia have shown significant enhancement in rhizosphere enzyme activities up to 65%, metabolites up to 51% and nutrient uptake up to 52% whereas, physical growth showed the increment in the range of 10–59% over the uninoculated control. Treatment of Azotobacter + organic manure + NPK 50% has been found to enhance maximum growth in most of the parameters significantly, followed by AMF + organic manure + NPK 50% treatment, while Azospirillum showed its highest impact in enhancing enzyme activities and nitrogen uptake in comparison to Azotobacter and AMF. Legume tree and crop species showed significant response towards the nitrogen fixation thus helped in improving the nutritional value of the mine spoil. Hence, the integrated approach of agro-silviculture practices using legumes and bioinoculants can play a key role in the rehabilitation of feldspar mine spoil.