Enhanced Carbon Uptake and Reduced Methane Emissions in a Newly Restored Wetland

Wetlands play an important role in reducing global warming potential in response to global climate change. Unfortunately, due to the effects of human disturbance and natural erosion, wetlands are facing global extinction. It is essential to implement engineering measures to restore damaged wetlands. However, the carbon sink capacity of restored wetlands is unclear. We examined the seasonal change of greenhouse gas emissions in both restored wetland and natural wetland and then evaluated the carbon sequestration capacity of the restored wetland. We found that (1) the carbon sink capacity of the restored wetland showed clear daily and seasonal change, which was affected by light intensity, air temperature, and vegetation growth, and (2) the annual daytime (8–18 hr) sustained-flux global warming potential was −11.23 ± 4.34 kg CO₂ m⁻² y⁻¹, representing a much larger carbon sink than natural wetland (−5.04 ± 3.73 kg CO₂ m⁻² y⁻¹) from April to December. In addition, the results showed that appropriate tidal flow management may help to reduce CH₄ emission in wetland restoration. Thus, we proposed that the restored coastal wetland, via effective engineering measures, reliably acted as a large net carbon sink and has the potential to help mitigate climate change.