Effect of Heavy Metals on Activities of Soil Microorganism

Heavy metals are ubiquitous elements, and some of them play unique roles in biological systems. They are key components of soil as some of them are eco-friendly in their geochemical state. The continual increase in their concentration due to the increasing anthropogenic influences such as mining, agricultural process, and combustion of fossil fuels among others is the cause for concern. Most of these metals though present in various components of the environment are more concentrated in the soil, which acts as a natural storeroom for environmental waste from all other media. The high content of these metals in soil is toxic not only to plants and animals but also to microorganisms that play an indispensable role in soil and aid the sustenance of natural cycles. This chapter examines the effect of heavy metal on soil microorganisms. The effect of heavy metals on microbial biomass, population, activities, and diversity is discussed. The methods for assessing heavy metal tolerance in microorganisms are also presented, and finally a brief review on the mechanisms of adaptation of soil microorganisms to high concentration of heavy metals is also provided.