JOURNAL of Soil Biology and Ecology

Below-ground microbial diversity and bioremediation of contaminated soils

Author: R. LAKSHMIPATHY 1 AND A.N. BALAKRISHNA

Abstract :

Soil is a finite and non-renewable resource because the regeneration of soil through chemical and biological weathering of underlying rock requires geological time (Huber et al., 2001). Soil supports all forms of life on the earth, including microorganisms. Deterioration of soil and soil health concerns human, animal and plant health. Microbial diversity-affected soil is mismanaged or contaminated (Singer et al., 2000). Hence, it is essential to maintain soil health in terms of biological, chemical and physical features of soil that are essential to long-term sustainable agricultural productivity with minimal environmental impact. There is also increased interest in studying soil microorganisms in their particular environments, as soil microbial diversity is intimately related to soil structure and function. Soil microorganisms are key players in the global cycling of organic matter, reworking organic residues or mineralising them to CO2, H2O, N, P, S and other nutrients (Bloem et al., 1997). The nutrients immobilised in microbial biomass are released when microbes are grazed by microbivores such as protozoa and nematodes. The continued capacity of soil is to function as a vital living system within the ecosystem and land-use boundaries, to sustain biological productivity, promote the quality of air and water environments and maintain plant, animal and human health.

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