Mangrove Microbiomes: Biodiversity, Ecological Significance, and Potential Role in the Amelioration of Metal Stress (Chapter 4)

Abstract

The mangrove ecosystem through a rich productive ecosystem with a great diversity of flora and fauna both macro and micro is under the threat of severe pollution stress due to anthropogenic interference. Continuous input of pollutants is a major threat to this ecosystem affecting the indigenous microbial community playing a major role in the biogeochemical reactions and contributing to the richness of the biome. Being exposed to inputs from riverine sources which in turn receive huge amounts of pollutants in the form of industrial effluent discharge, agricultural runoff, domestic waste, sewage, etc., the major components in these discharges are pesticides, excessive inorganic compounds, high organic content, and metals. These pollutants especially the heavy metals tend to sink, have low solubility in water, and accumulate in the mangrove sediments, which act as the sinks for the heavy metals. Sediment contamination thus ultimately diminishes the mangrove ecosystem. Exposure to the pollutants especially heavy metals results in changes in the microbial communities with the prevalence of metal-tolerant species. This chapter uncovers the ecological aspects of mangrove sediments focusing on the metal-tolerant microbiome and its role in the maintenance of the biome.