Diurnal variations of pCO2 in relation to environmental factors in the cascade reservoirs along the Wujiang River, China

• Published in: Acta geochimica 2012-03, Vol.31 (1), p.41-47
• Main Authors: Peng, Xi, Wang, Baoli, Liu, Congqiang, Liu, Xiaolong, Wang, Fushun
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Climate; Diurnal variations; Earth and Environmental Science; Earth Sciences; Environmental factors; Eutrophication; Geochemistry; Phytoplankton; Reservoirs; Rivers; Surface water; Trophic levels; Water column; Water depth
• ISSN: 1000-9426; 2096-0956; 1993-0364; 2365-7499
• DOI: 10.1007/s11631-012-0547-5

We have investigated the diurnal variations of the p CO 2 and related environmental factors in the cascade reservoirs with different trophic levels along Wujiang River. In surface water the p CO 2 was 357±11 μatm in Hongjiadu Reservoir, 338±48 μatm in Dongfeng Reservoir, 682±303 μatm in Wujiangdu Reservoir, and 1677±429 μatm in Liuguang, respectively. The results indicated that these cascade reservoirs had much lower p CO 2 values in surface water than river did, and hypereutrophic reservoir showed larger diurnal variations of p CO 2 than meso-eutrophic reservoir. In water column, p CO 2 tended to increase with the depth. Phytoplankton and the environmental factors such as temperature and pH had different influences on p CO 2 diurnal variations due to different trophic levels, and the effect of phytoplankton on p CO 2 variation increased with the increase of trophic level in these reservoirs.