Cross-Sectional Variations in Structure and Function of Coral Reef Microbiome With Local Anthropogenic Impacts on the Kenyan Coast of the Indian Ocean

Abstract

Coral reefs face an increased number of environmental threats from anthropomorphic climate change and pollution from agriculture, industries and sewage. Because environmental changes lead to their compositional and functional shifts, coral reef microbial communities can serve as indicators of ecosystem impacts through development of rapid and inexpensive molecular monitoring tools. Little is known about coral reef microbial communities of the Western Indian Ocean (WIO). We compared taxonomic and functional diversity of microbial communities inhabiting near-coral seawater and sediments from Kenyan reefs exposed to varying impacts of human activities. Over 19,000 species (bacterial, viral and archaeal combined) and 4,500 clusters of orthologous groups of proteins (COGs) were annotated. The coral reefs showed variations in the relative abundances of ecologically significant taxa, especially copiotrophic bacteria and coliphages, corresponding to the magnitude of the neighboring human impacts in the respective sites. Furthermore, the near-coral seawater and sediment metagenomes had an overrepresentation of COGs for functions related to adaptation to diverse environments. Malindi and Mombasa marine parks, the coral reef sites closest to densely populated settlements were significantly enriched with genes for functions suggestive of mitigation of environment perturbations including the capacity to reduce intracellular levels of environmental contaminants and repair of DNA damage. Our study is the first metagenomic assessment of WIO coral reef microbial diversity which provides a much-needed baseline for the region, and points to a potential area for future research toward establishing indicators of environmental perturbations.

The soil microbiomes of forest ecosystems in Kenya: their diversity and environmental drivers

“…In addition, factors that modify the microclimate and forest litter chemistry such as forest type, plant species and plant diversity have also been identi ed as drivers of microbial community composition in forest soils [35][36][37] . Kenya's indigenous forests represent some of the most diverse ecosystems in the world, and provide important economic, environmental, recreational, scienti c, cultural and spiritual bene ts to the nation (Republic of Kenya, 2009) [38][39][40] . Forests play a vital role in the stabilization of soils and ground water, support the conduct of reliable agricultural activity and play a crucial role in protecting water catchments in Kenya besides moderating climate by absorbing greenhouse gases [41][42][43][44][45] .…”

Plasticity of the Anemonia viridis microbiota in response to different levels of combined anthropogenic and environmental stresses

“…Marine coastal ecosystems are known to provide a wide range of ecological and economically important services, including habitat provision, nutrient cycling, coastal protection, fisheries enhancement, and, of course, tourism (Trevathan-Tackett et al, 2019). However, the current and future climate change scenarios are jeopardizing the health of coastal ecosystems, which are already extremely vulnerable, due to the continuous threats from various anthropogenic pressures (Crain et al, 2009;Wambua et al, 2021). In this scenario, it is extremely important to better understand the response of coastal habitat-forming species to local and global stressors, dissecting their inherent limit of adaptability to the anthropogenic pressures, thus allowing the implementation of sustainable practices for the management, preservation, and restoration of coastal ecosystems (Santoro et al, 2021).…”