Based on the data obtained monthly from 2000 to 2014, temporal and spatial distributions of dissolved organic nitrogen (DON) concentration in the Shenzhen Bay and coastal southeastern Pearl River Estuary were analyzed. Also sources and bioavailability of the DON were investigated in combination with the salinity, 5-d biochemical oxygen demand and particulate organic matter measurements. The results showed that the DON concentration was 0.45±0.45mg/L with an increase trend from 2000 to 2004 and a decrease one from 2005 to 2014 and higher in summer and winter than spring and autumn in the bay, and 0.16±0.08mg/L with small seasonal changes and an increase trend in the whole period studied in the estuary. The DON appeared conservative and was from simultaneous sources in both of the bay and estuary. A two-component mixing mass balance model was used for estimating the DON terrestrial fraction at about 80% in the bay and 38% in the estuary, suggesting that the DON was mainly from the terrestrial sources in the bay but from the marine sources in the estuary. According to the measurements and regression results, the DON bioavailability was found to be about 14.8% and 15.5% in the bay and estuary respectively, nearly equal to the dissolved organic carbon bioavailability observed in the lower Pearl River Estuary.
李绪录, 许春玲, 林梵, 史华明, 张军晓. 深圳湾及邻近水域中的溶解有机氮——其时空分布、来源和生物利用率[J]. 中国环境科学, 2016, 36(9): 2757-2764.
LI Xu-lu, XU Chun-ling, LIN Fan, SHI Hua-ming, ZHANG Jun-xiao. Dissolved organic nitrogen in the Shenzhen Bay and adjacent coastal waters: Its temporal and spatial distributions, sources and bioavailability. CHINA ENVIRONMENTAL SCIENCECE, 2016, 36(9): 2757-2764.
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