title: Temporal dynamics and drivers of ecosystem metabolism in a large subtropical shallow lake (lake Taihu).
abstract: With continuous measurements of dissolved oxygen, temperature, irradiance, and wind speed, as well as frequent measurements of pH, oxidation-reduction potential, and algal chlorophyll, temporal dynamics and drivers of ecosystem metabolism in a large nutrient-rich shallow lake (Lake Taihu) are tested in this study. The results show that the dissolved oxygen concentrations in the lake fluctuate annually. They increase in autumn and winter with a peak value of 14.19 mg·L-1 in winter, and decrease in spring and summer with a trough value of 6.40 mg·L-1 in summer. Gross primary production (GPP), ecosystem respiration (R), and net ecosystem production (NEP) increase in summer, with their peak values in late summer and autumn, and decrease in winter and spring. Mean values of GPP, R and NEP are 1.75 ± 0.06 (Mean ± SE), 1.52 ± 0.05, and 0.23 ± 0.03 g O2 m-3·d-1, respectively. It is also found that water temperature and surface irradiance are the best predictors of GPP and R, while water temperature (wind speed) has a significantly positive (negative) relationship with NEP. The findings in this study suggest that Lake Taihu is a net autotrophic ecosystem, and water temperature and surface irradiance are the two important drivers of lake metabolism.
authors.affiliation: Yale-NUIST Center on Atmospheric Environment, Jiangsu Key Laboratory of Agricultural Meteorology & Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China. zhhu@nuist.edu.cn.
authors.forename: Zhenghua
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Yale-NUIST Center on Atmospheric Environment, Jiangsu Key Laboratory of Agricultural Meteorology & Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China. qitaoxiao@163.com.
authors.forename: Qitao
authors.initials: Q
authors.lastname: Xiao
authors.affiliation: Jiangsu Meteorological Bureau, Nanjing 210008, China. yangjb1979@gmail.com.
authors.forename: Jinbiao
authors.initials: J
authors.lastname: Yang
authors.affiliation: Yale-NUIST Center on Atmospheric Environment, Jiangsu Key Laboratory of Agricultural Meteorology & Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China. xiaowei_522@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Xiao
authors.affiliation: Yale-NUIST Center on Atmospheric Environment, Jiangsu Key Laboratory of Agricultural Meteorology & Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China. wangw@nuist.edu.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Yale-NUIST Center on Atmospheric Environment, Jiangsu Key Laboratory of Agricultural Meteorology & Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China. lsd@nuist.edu.cn.
authors.forename: Shoudong
authors.initials: S
authors.lastname: Liu
authors.affiliation: School of Forestry and Environmental Studies, Yale University, New Haven, CT 06511, USA. xuhui.lee@yale.edu.
authors.forename: Xuhui
authors.initials: X
authors.lastname: Lee
mesh_terms: D052818:Autotrophic Processes; D057919:Biological Oxygen Demand Analysis; D002681:China; D017753:Ecosystem; D060106:Lakes / Q000032:analysis / Q000737:chemistry*; D012621:Seasons; D060753:Water Quality
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