Conclusion
Soil MBC increased in all plantations during the 8thand 25th year of reclamation and was much higher underAzadirachta indica plantation than recently dumped soil. Among four different pools of organic carbon, the carbon per cent was highest in the non-labile pool of carbon and it had increased with increase in year of reclamation except in the case of Dalbergia sissoo . Non-labile carbon pool was highest under Azadirachta indicia and very labile, labile pool of carbon was highest under Gmelina arborea . Reclamation increased soil organic C stock of soil under all tree species, highest in case of Azadirachta indica . Recalcitrance index 2 was highest in case of Azadirachta indicaand recalcitrance index 1 was lowest under Azadirachta iindicawhich suggested more stability of SOC in case of Azadirachta indica . Carbon content and C/N ratio of humic acid were significantly highest under Azadirachta indica plantation. TOC content was highest under Azardichta indica but aromaticity was highest underGmelina arborea as obtained by E4/E6 and EET: EBZ ratio. FT-IR spectra of restored mine soil indicated that in the case of Azadirachta indica, Dalbergia sissoo andGmelina arborea relative proportions of aromatic groups along the chronosequence increased indicating higher proportions of resistant SOC components in the older mine soils. Overall, the results indicated that with the increase in year of reclamation accumulation of SOC and improvement of SOC pools took place and its highest underAzadirachta indica . Spectroscopic methods results were also clearly able to distinguish improvement in reclamation process with increase in year of reclamation.

Acknowledgments

We thank Dr. P Dwivedi and Dr. H.B Singh (Institute of Agricultural Sciences, BHU, India) for linguistic support. We also thank Mr. R.S Singh for valuable discussion during preparation of the first draft of the manuscript. The authors are very grateful for funding provided through an PhD scholarship, University Grant Commission, provided through the Banaras Hindu University.