Hypoxia is a common phenomenon in the sea adjacent to the Changjiang River Estuary(CJE),one of the global major estuaries.Submarine groundwater discharge(SGD)is a widely recognized pathway for terrestrial materials en...Hypoxia is a common phenomenon in the sea adjacent to the Changjiang River Estuary(CJE),one of the global major estuaries.Submarine groundwater discharge(SGD)is a widely recognized pathway for terrestrial materials entering the sea,and has been found to be significant off the CJE.We used a^(222)Rn mass balance model to estimate the SGD fluxes off the CJE and showed that it is linked to seasonal dissolved oxygen(DO)variations.Average SGD fluxes were estimated to be(0.012±0.010)m^(3)/(m^(2)·d)in winter,(0.034±0.015)m^(3)/(m^(2)·d)in summer,and(0.020±0.010)m^(3)/(m^(2)·d)in autumn.We found a significant negative correlation between DO concentrations and SGD rates with groundwater discharge being highest in the summer flood season.In addition,distribution patterns of SGD and hypoxia zones in summer are spatially overlapped,indicating that SGD is an important contributor to summer hypoxia in this region.展开更多
基金The National Natural Science Foundation of China under contract Nos 42130410 and U22A20580the Fundamental Research Funds for the Central Universities under contract No.202341002.
文摘Hypoxia is a common phenomenon in the sea adjacent to the Changjiang River Estuary(CJE),one of the global major estuaries.Submarine groundwater discharge(SGD)is a widely recognized pathway for terrestrial materials entering the sea,and has been found to be significant off the CJE.We used a^(222)Rn mass balance model to estimate the SGD fluxes off the CJE and showed that it is linked to seasonal dissolved oxygen(DO)variations.Average SGD fluxes were estimated to be(0.012±0.010)m^(3)/(m^(2)·d)in winter,(0.034±0.015)m^(3)/(m^(2)·d)in summer,and(0.020±0.010)m^(3)/(m^(2)·d)in autumn.We found a significant negative correlation between DO concentrations and SGD rates with groundwater discharge being highest in the summer flood season.In addition,distribution patterns of SGD and hypoxia zones in summer are spatially overlapped,indicating that SGD is an important contributor to summer hypoxia in this region.
