文献类型：期刊文献

英文题名：Oyster cultivation regulating seasonal nitrate cycling in the estuarine water

作者：Zhou, Xin[1];Song, Zhiguang[2];Chen, Chunqing[1,3];Zhu, Qingmei[3];Chen, Fajin[1,3]

机构：[1]Guangdong Ocean Univ, Coll Chem & Environm, Zhanjiang 524088, Peoples R China;[2]Nanning Normal Univ, Key Lab Environm Change & Resources Use Beibu Gulf, Minist Educ, Nanning 530001, Guangxi, Peoples R China;[3]Guangdong Ocean Univ, Coll Ocean & Meteorol, Zhanjiang 524088, Peoples R China

年份：2025

卷号：220

外文期刊名：MARINE POLLUTION BULLETIN

收录：SCI-EXPANDED(收录号：WOS:001540321100001)、、EI(收录号：20252818762240)、Scopus(收录号：2-s2.0-105010188762)、WOS

基金：The authors thank Shangjun Cai and Guirong He at Guangdong Ocean University for providing nitrifier genes and denitrifiers genes analysis. This work was supported by program for scientific research start-up funds of Guangdong Ocean University (060302122501), the Guangxi Science and Technology Plan Project (AD22035046), the National Natural Science Foundation of China (92158201, 42376001, U1901213), the Innovation and Entrepreneurship Project of Shantou (2021112176541391), and the Scientific Research Start-Up Foundation of Shantou University (NTF20006).

语种：英文

外文关键词：Nitrogen; Nitrate dual isotopes; Source; Oyster; Zhanjiang Bay

外文摘要：Effects of oyster cultivation on nitrate (NO3-) cycling exhibit discrepancies between model results and filed studies, necessitating seasonal investigations to clarify these differences. By combining geochemical analysis including water chemistry, NO3- dual isotopes (delta N-15-NO3- and delta O-18-NO3-), and N-cycling functional genes (nitrifier genes and denitrifier genes), this study found that NO3- cycling is regulated by oyster growth activities. During the oyster's seeding periods, oyster cultivation insignificantly affected NO3-, and NO3- displayed a conservative pattern in the estuarine waters. Bayesian mixing model showed that manure and sewage were primary NO3- sources (>50 %), followed by atmospheric deposition (23 %). During the oysters' breeding periods, suspended particulate matter accumulation and relatively high abundance of AOA amoA gene in particle-associated communities promoted particulate matter associated nitrification. In the oysters' high filter-feeding periods, NO3- consumption (assimilation) occurred in surface water and NO3- production (nitrification) occurred in bottom water, as supported by increased nitrifier abundances. The increased nitrification was related to the consumption of NO3-, and thus gives rise to the remaining NH4+ nitrified to NO3-. In the oysters' intensive filter-feeding periods, intensive nutrients demanding by oyster growth caused significant decrease in NO3- concentrations in estuarine waters. However, massive discharge of oyster feces into surface sediments may stimulate partial denitrification in the sediments and nitrification in the waters, leading to the decoupling of delta N-15-NO3- and delta O-18-NO3- against ln [NO3-]. Overall, nitrification and partial denitrification in the estuarine ecosystems driven by oyster cultivation may be conducive to the production of nitrous oxide.