Details

Autor(en) / Beteiligte

• Chen, Fajin
• Chen, Jianfang
• Jia, Guodong
• Jin, Haiyan
• Xu, Jie
• Yang, Zhi
• Zhuang, Yanpei
• Liu, Xizhen
• Zhang, Haisheng

Titel

Nitrate delta super(15)N and delta super(18)O evidence for active biological transformation in the Changjiang Estuary and the adjacent East China Sea

Ist Teil von

• Acta oceanologica Sinica, 2013-04, Vol.32 (4), p.11-17

Erscheinungsjahr

2013

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The Changjiang Estuary has been considered as one of the most polluted estuaries in the world due to high nitrate (NO super(-) sub(3)) input, especially in spring and summer. In this study, delta super(15)N and delta super(18)O of NO super(-) sub(3), along with other chemical parameters in this area, were measured in spring to evaluate NO super(-) sub(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 super(-) sub(3) sources in the Changjiang Estuary and the adjacent East China Sea. The isotopic signals show that NO super(-) sub(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 delta super(15)N and delta super(18)O in the three transects, while spatial difference in nitrification was reflected by deviations of delta super(15)N and delta super(18)O from assimilation line. Our results suggest that the input of the Changjiang River Diluted Water promoted NO super(-) sub(3) assimilation possibly by stratifying the water column which favored the phytoplankton growth.