Impact of Anthropogenic Activities on Microbially Mediated Carbon Dioxide and Methane Emissions in Wetlands: A Review and Prospects

Global wetlands play a significant role as “blue carbon sinks”. Despite their relatively small coverage, they have enormous potential for carbon capture and sequestration, and also serve as an important natural source of atmospheric carbon dioxide (CO2) and methane (CH4). Wetland ecosystems are characterized by complex microbial interactions that mediate carbon (C) cycling processes, and also directly influence the dynamic changes of CO2 and CH4, underscoring the crucial role of microorganisms in these systems. Understanding the ecological significance of these gases and their response mechanisms to environmental changes is vital for mitigating the greenhouse effect and conserving ecosystems. This paper reviewed the major environmental challenges facing wetlands globally, such as salinization, over-fertilization, heavy metal input, and microplastic pollution, all influenced by human activities. Additionally, it examined their impact on microbial interactions that mediate the carbon cycle and related greenhouse gas emissions. This review highlighted the crucial role of microorganisms in these cycles and provided a microbial ecological perspective and theoretical foundation for promoting sustainable development and reducing greenhouse gas emissions in wetland areas.