Temporal Dynamics and Drivers of Ecosystem Metabolism in a Large Subtropical Shallow Lake (Lake Taihu)

International Journal of Environmental Research and Public Health

Jinbiao Yang¹  Xuhui Lee²  Wei Wang³  Wei Xiao³  Zhenghua Hu³  Qitao Xiao³  Shoudong Liu³ 

[1] Jiangsu Meteorological Bureau, Nanjing 210008, China;School of Forestry and Environmental Studies, Yale University, New Haven, CT 06511, USA;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;

关键词: lake metabolism;    dissolved oxygen;    gross primary production;    ecosystem respiration;    net ecosystem production;    shallow lake;   

DOI  :  10.3390/ijerph120403691

来源: DOAJ

【 摘 要 】

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.

【 授权许可】

Unknown