Effects of Human Activities on Microorganisms and Microbial Carbon Cycle in Coastal Waters

Coastal areas, which carry over 50% of the world's population, are essential to humankind because they offer abundant resources for trade, transportation, fisheries, tourism, and scientific research. Importantly, the microbial communities and microbial carbon cycles in the coastal waters are significantly impacted by human activities. In particular, human-produced pollutants have an impact on the reproduction and survival of microorganisms along the coast. For example, pollutants such as heavy metals and oil can affect the photosynthesis and decomposition processes of microorganisms, thereby affecting the carbon cycle. Meanwhile, aquaculture may also change the community and quantity of microorganisms in coastal waters -- the excreta and residual bait of cultured fish can provide nutrition which promotes the growth and reproduction of microorganisms. Moreover, overfishing can lead to a decrease in the number of fish and other organisms, which in turn affects the decomposition of organic matter and the release of carbon. Another major consideration is coastal tourism activities may introduce alien species, especially microorganisms. These alien species may compete with local microorganisms for living space and resources, posing a threat to the local microbial community. Due to the huge impact of human activities on coastal microorganisms, it is vital to explore more about the mechanisms and environmental effects of microbial communities and the microbial carbon cycle in coastal waters.

To better protect and manage marine ecosystems, it is necessary to conduct in-depth research on the mechanisms of interaction among various microbial and human communities in coastal areas. With interdisciplinary and international cooperation, we can better understand and respond to the impact of human activities on microbial communities as well as the carbon cycle of coastal microorganisms, providing a better scientific view for the protection and management of coastal ecosystems.

This Research Topic calls for Original Research articles, Reviews, Mini-Reviews, Opinions, and Perspectives related to microbial community and the microbial carbon cycle in coastal waters affected by human activities with any of the following sub-topics, but are not limited to:
· Key processes and mechanisms of microbial carbon cycle in coastal areas
· Key microorganisms affecting carbon fixation under different human interferences
· Changes in microbial community and carbon cycle driven by human activities
· New microbial community analysis methods and models