富营养化
环境科学
碳循环
营养物
二氧化碳
无机碳总量
亚热带
生态系统
远洋带
叶绿素a
浮游植物
水文学(农业)
海洋学
生态学
生物
地质学
岩土工程
植物
作者
Qitao Xiao,Xiaofeng Xu,Hongtao Duan,Tianci Qi,Boqiang Qin,Xuhui Lee,Zhenghua Hu,Wei Wang,Wei Xiao,Mi Zhang
出处
期刊:Water Research
[Elsevier]
日期:2020-03-01
卷期号:170: 115331-115331
被引量:85
标识
DOI:10.1016/j.watres.2019.115331
摘要
Inland lakes receive growing attentions on eutrophication and their roles in global carbon cycle. However, understanding how inland lakes contribute to global carbon cycle is seriously hampered due to a shortage of long-term records. This study investigated the carbon dioxide (CO2) flux from the Lake Taihu, a large (2400 km2) and shallow (mean depth 1.9 m) eutrophic lake in subtropical region, based on a long-term (2000-2015) measurement of the partial pressure of carbon dioxide (pCO2) at high spatiotemporal resolution. We found that the Lake Taihu was a significant source of atmospheric CO2 with an average CO2 emission flux at 18.2 ± 8.4 mmol m-2 d-1 (mean±1standard deviation) and a mean annual pCO2 value of 778 ± 169 μatm. The highest pCO2 and CO2 flux were observed in eutrophic zone with a high external input of carbon and nutrient, and the lowest in non-eutrophic zones with no direct external input of nutrient and carbon. A substantial seasonal pattern in pCO2 was observed, particularly in eutrophic pelagic area, and was significantly negatively correlated with chlorophyll a. Long-term measurement showed the interannual variation in annual lake CO2 dynamics, which was highly sensitive to human-induced nutrient input. Watershed input of carbon and nutrient leads to the high CO2 level, counterbalancing the in-lake primary production. All lines of evidence suggest that human activities may have predominate contribution to CO2 source in the Lake Taihu, and this mechanism might be widespread in global freshwater lakes.
科研通智能强力驱动
Strongly Powered by AbleSci AI