naa a22 4500 510754392 CHVBK 20180411083117.0 cr unu---uuuuu 180411e20130401xx s 000 0 eng 10.1007/s13131-013-0294-4 doi (NATIONALLICENCE)springer-10.1007/s13131-013-0294-4 Nitrate δ 15N and δ 18O evidence for active biological transformation in the Changjiang Estuary and the adjacent East China Sea [Elektronische Daten] [Fajin Chen, Jianfang Chen, Guodong Jia, Haiyan Jin, Jie Xu, Zhi Yang, Yanpei Zhuang, Xizhen Liu, Haisheng Zhang] The Changjiang Estuary has been considered as one of the most polluted estuaries in the world due to high nitrate (NO 3 − ) input, especially in spring and summer. In this study, δ 15N and δ 18O of NO 3 − , along with other chemical parameters in this area, were measured in spring to evaluate NO 3 − biogeochemical processes. A simple two end-members mixing model was used to examine the relative contribution of the Changjiang River Diluted Water and marine water to NO 3 − sources in the Changjiang Estuary and the adjacent East China Sea. The isotopic signals show that NO 3 − behaved relatively and conservatively in Transect F and Transect P where assimilation was weak possibly due to vertical mixing, while active assimilation and weak nitrification occurred in Transect D. Spatial difference in assimilation was indicated by the ∼1:1 enrichment of δ 15N and δ 18O in the three transects, while spatial difference in nitrification was reflected by deviations of δ 15N and δ 18O from assimilation line. Our results suggest that the input of the Changjiang River Diluted Water promoted NO 3 − assimilation possibly by stratifying the water column which favored the phytoplankton growth. The Chinese Society of Oceanography and Springer-Verlag Berlin Heidelberg, 2013 Changjiang Estuary nationallicence nitrate nationallicence nitrogen isotope nationallicence oxygen isotope nationallicence Chen Fajin State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut Chen Jianfang State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut Jia Guodong Key Laboratory of Marginal Sea Geology of Chinese Academy of Sciences, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China aut Jin Haiyan Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut Xu Jie Division of Environment, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China aut Yang Zhi Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut Zhuang Yanpei Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut Liu Xizhen Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut Zhang Haisheng Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut Acta Oceanologica Sinica The Chinese Society of Oceanography 32/4(2013-04-01), 11-17 0253-505X 32:4<11 2013 32 13131 https://doi.org/10.1007/s13131-013-0294-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s13131-013-0294-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chen Fajin State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut NATIONALLICENCE 700 1- Chen Jianfang State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut NATIONALLICENCE 700 1- Jia Guodong Key Laboratory of Marginal Sea Geology of Chinese Academy of Sciences, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 510640, Guangzhou, China aut NATIONALLICENCE 700 1- Jin Haiyan Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut NATIONALLICENCE 700 1- Xu Jie Division of Environment, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China aut NATIONALLICENCE 700 1- Yang Zhi Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut NATIONALLICENCE 700 1- Zhuang Yanpei Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut NATIONALLICENCE 700 1- Liu Xizhen Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut NATIONALLICENCE 700 1- Zhang Haisheng Laboratory of Marine Ecosystem and Biogeochemistry of State Oceanic Administration, Second Institute of Oceanography, State Oceanic Administration, 310012, Hangzhou, China aut NATIONALLICENCE 773 0- Acta Oceanologica Sinica The Chinese Society of Oceanography 32/4(2013-04-01), 11-17 0253-505X 32:4<11 2013 32 13131 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer