Impact Of Microbial Biomass And Basal Soil Respiration In Soil Enzyme Activities In Seven Different Chronosequence Mine Spoil

Abstract

The objective of the current study is to determine the potential of microbial biomass and basal soil respiration to improve the rate of soil enzyme activity on polluted land. The soil enzyme activities (amylase, invertase, protease, urease and dehydrogenase) were determined from the six different soil profiles collected from the Kanthar Manganese mine, Koira, Sundergarh, Odisha, and sampling was done in chronosequence, i.e., fresh mine spoil (MBO0), two-year-old mine spoil (MBO2), 4-year-old (MBO4), 6-year-old (MBO6), 8-year-old (MBO8), and 10-year-old (MBO10) mine spoil, and compared with nearby forest soil (FS). The activities of soil enzymes were increasing from fresh mine spoil (MBO0) to MBO 10, and the highest activity was seen in forest soil (FS), which may be due to improvement in the soil organic carbon and total nitrogen concentration that showed significant correlation at the p < 0.01 level of significance. Further, stepwise multiple regression analysis has shown positive regulation of soil pH, moisture, and clay content in the improvement of enzyme activities in disturbed areas. Additionally, the accumulation of microbial biomass carbon (MB-C), microbial biomass nitrogen (MB-N), microbial biomass phosphorus (MB-P) and basal soil respiration (BSR) concentration was increasing from fresh mine spoil to forest soil, which may facilitate the improvement of soil enzyme activities. Principal component analysis indicates the effect of physicochemical properties and microbial biomass on enzyme activities and is presented as seven independent clusters. Such studies indicate a reliable and comprehensive idea of any alteration in soil quality and modification that occurred due to exposure to heavy metal stress.