Journal of Pure and Applied MicrobiologyVol. 9 No. 4

Redevelopment Of Soil Carbon Pools and Biological Properties on Restored Mine Spoils Under Plantation

Preeti Singh, Shankar Ram, Hemant Jayant and A. K. Ghosh*

Department of Soil Science & Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi-221005, India.

Received on 25 September 2015 and accepted on 12 November 2015

 

ABSTRACT

Mining causes soil disturbance and creates a huge load of overburden that disturbs the ecosystem and poses environmental problems. Restoration of overburden dumps by planting trees is an economical process of soil conservation that stabilizes the soil. The study was made on an overburden chronosequence of the largest coal mining project of Asia to unravel the relationship of carbon pools and biological properties on soil redevelopment. Organic carbon status of soils under various years of restoration increased substantially from 0.1 g kg-1 in fresh dump to 37.8 g kg-1 under 25 years of restoration, which was complimented by concomitant increase in microbial biomass carbon during the period from nil to 316.8 ?g g-1 and was also strongly correlated to it (r=0.97*). The rate of carbon mineralization also closely followed microbial biomass carbon and increased from 84 in fresh dumps to 396 mg CO2 C -1 kg soil -1day -1 after 25 years of restoration and was strongly related to organic carbon (r=0.99*) and microbial biomass (r=0.99*) of soil. The dehydrogenase enzyme activity also increased from 7.28 to 15.9 ?g TPF g-1 soil day-1 during the restoration period. The proportion of soil carbon in microbial biomass was small (0.84 to 1%) and the labile fraction decreased while the resistant fraction increased (from 0 to 41%) over the years of restoration suggesting the carbon was being stabilized into stable pools.

Keywords : Mine spoil, reclamation, biological properties, carbon pools.