Concentrations of dissolved CO2 and NO3− were investigated in cascade reservoirs and related river reaches along the Wujiang River to understand temporal and spatial variations. The average of dissolved CO2 were (113.6±105.7) μmol·L−1, ranging from 1.6 to 934.6 μmol·L−1. The average of NO3− were (163.0±104.9) μmol·L−1, ranging from 0.4 to 632.0 μmol·L−1. Averages and amplitudes of dissolved CO2 and NO3− in the reservoirs are less than those in the rivers. Due to different resources and influencing factors, no significant correlation was found between dissolved CO2 and NO3− in rivers. After damming, the activity of phytoplankton was enhanced, and became an important factor controlling material cycle in reservoirs. Photosynthesis and respiration couple C and N biogeochemical cycle, and dissolved CO2 and NO3− in reservoirs were significantly correlated. The results indicate that C and N biogeochemical cycles in the original rivers are changed by cascade hydropower exploitation.
WANG Bao-Li, LIU Cong-Jiang, WANG Fu-Shun, LIU Xiao-Long, PENG Xi, ZHAO Yan-Chuang
. Carbon and nitrogen coupled biogeochemical cycle in cascade reservoirs of the Wujiang River[J]. Journal of Shanghai University, 2015
, 21(03)
: 294
-300
.
DOI: 10.3969/j.issn.1007-2861.2015.01.013
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