Characteristics of methane emission in a typical artificial landscape pond and its response to eutrophication
The carbon cycling process in eutrophic water bodies has always been a prominent and critical concern in global aquatic ecosystems.This study conducted a year-long in-situ investigation of methane(CH4)flux at the water-air interface in the campus landscape pond(Lianxin Pond)of China Three Gorges University.This study aims to assess the influence of eutrophication on CH4 emissions.The findings revealed a CH4 emission flux rate of 5.06 m g/(m2·h)at the water-air interface,contributing to atmospher-ic CH4 levels.The CH4 flux was influenced by temperature,wind speed,and chlorophyll-a,while showed significant temporal het-erogeneity with the following order:summer(8.70 mg/(m2·h))＞winter(4.80 mg/(m2·h))＞spring(3.88 mg/(m2·h))＞au-tumn(2.87 mg/(m2·h)).Furthermore,the dominant pathway was identified as bubbling(the proportion of bubbling is 88.56％),during the day(0.11 mg/(m2·h))slightly higher than the night(0.09 mg/(m2·h)).The difference of CH4 emission flux in different seasons and day and night is related to the change of environmental factors such as temperature,wind speed and chlorophyll-a.With the increase of water eutrophication level,the CH4 emission flux showed a non-linear increase trend.With the increase of eutrophication level,the release flux of CH4 release flux showed nonlinear increase.Notably,the mean CH4 flux in hy-per-eutrophic water was 2 times greater than that in moderately eutrophic water.Controlling eutrophication is critical to reducing CH4 emissions from water bodies,and can serve as a reference for reducing greenhouse gas emissions in other similar aquatic eco-systems.
万方数据
维普
