文献类型：期刊文献

英文题名：Spatiotemporal Urea Distribution, Sources, and Indication of DON Bioavailability in Zhanjiang Bay, China

作者：Zhang, Peng[1];Peng, Cong-Hui[1];Zhang, Ji-Biao[1,2];Zou, Zhan-Bin[1];Shi, Yu-Zhen[1];Zhao, Li-Rong[1];Zhao, Hui[1,2]

机构：[1]Guangdong Ocean Univ, Fac Chem & Environm Sci, Zhan Jiang 524088, Peoples R China;[2]Southern Lab Ocean Sci & Engn, Zhan Jiang 524088, Peoples R China

年份：2020

卷号：12

期号：3

外文期刊名：WATER

收录：SCI-EXPANDED(收录号：WOS:000529249500018)、、EI(收录号：20201508380084)、Scopus(收录号：2-s2.0-85082683093)、WOS

基金：This research was funded by Guangdong Ocean University (GDOU)'s University Scientific Research Fund for a Ph.D Start-up, (No. R18021), the Science and Technology Special Project of Zhanjiang city (2019B01081), and the First-class Special Funds of Guangdong Ocean University (231419018).

语种：英文

外文关键词：Zhanjiang Bay; seawater; urea; spatiotemporal distribution; terrestrial source input

外文摘要：In marine environments, urea is an important component of the biogeochemical cycle of nitrogen. The autochthonous and allochthonous sources (rivers, aquaculture, waste water input, etc.) of urea play a key role in urea cycles in adjacent coastal waters. Because urea is a specific marker to trace the sewage fluxes in coastal waters, we investigated urea associated with terrestrial source input and coastal water in Zhanjiang Bay (ZJB) during the time from November 2018 to July 2019, and the spatiotemporal urea distribution and the bioavailability of dissolved organic nitrogen (DON) based on urea concentration in the ZJB were explored. The results showed that the urea enrichment in coastal water was mainly due to discharge from urban sewage systems, rivers, and coastal aquaculture. The concentration of urea ranged from 1.14 to 5.53 mu mol.L-1, and its mean value was 3.13 +/- 1.02 mu mol.L-1 in the ZJB. The urea concentration showed a significantly different seasonal variation in the ZJB (p < 0.05), and the highest and lowest concentrations were found in November 2018 and April 2019, respectively. Its high value appeared in the north and northeast of the ZJB, which were polluted by coastal aquaculture and agriculture fertilizer utilization. The range of urea concentration of terrestrial source inputs in the ZJB was 1.31-10.29 mu mol.L-1, and the average urea concentration reached 3.22 +/- 0.82 mu mol.L-1. Moreover, the total urea flux surrounding the ZJB was 2905 tons.year(-1). The seasonal terrestrial source of urea flux contributions had significant seasonal variation in wet, normal, and dry seasons (p < 0.05). The ZJB was subjected to a large flux of urea by estuaries and sewage outlet discharges. The seasonal urea concentration in all stations (>1 mu mol.L-1) indicated that urea in the ZJB may have a bioavailable DON source. As a bioavailable nitrogen source, the ability of terrestrial source-derived urea to increase eutrophication should not be ignored in ZJB.