Rapid urbanization effects on partial pressure and emission of CO2 in three rivers with different urban intensities

摘要: Abstract Rapid urbanization has been reported to affect carbon biogeochemical cycle of waterways, contributing even higher dioxide (CO2) outgassing from rivers the atmosphere. However, knowledge on magnitude and extent influence riverine CO2 dynamics is still limited. In this study, we investigated partial pressure (pCO2) degassing rate in surface water three that drain land areas with varied urban coverages. Field sampling measurements were conducted Taohua, Nan Puli Rivers China’s mountainous Three Gorges Reservoir (TGR) area during winter 2018 summer 2019 determine effect intensity degassing. We found pCO2 level was significantly river increased proportion land. Both flux Taohua River (3872 μatm 574 mmol m−2 d−1) highest coverage than those (1737 218 mmol m−2 (1218 130 mmol m−2 less urbanized areas. No significant seasonal difference these subtropical (2402 ± 1421 vs 2112 ± 1254 winter). Overall, positively correlated concentration chlorophyll-a (Chl-a), nutrients (i.e., TDN TDP), dissolved organic (DOC) colony-forming units (CFU), negatively pH oxygen (DO). DOC loading better parameters for predicting draining more area, Chl-a area. These findings highlight role plays increasing through nutrient inputs drainage basin under development.