Abstract：Based on the data obtained from monthly cruises from 2000to 2010, temporal and spatial distributions of the dissolved organic nitrogen (DON) concentration in the Mirs Bay were briefly presented and discussed.The DON composition,sources and residence time (TDON) were approached by combining with the salinity, 5-day biochemical oxygen demand (BOD5), total dissolved nitrogen (TDN) and chlorophyll a (Chl a) measurements. The hydrodynamics in the Mirs Bay only posed a weak impact on the distributions of DON. The DON concentration was (0.15±0.08)mg/L, which was nearly equal to that in the Daya Bay, but lower than that in the Pearl River Estuary and higher than that in the coastal waters of the northern South China Sea. A two-component mixing mass balance model in combination with the DON fraction of TDN in the peripheral small rivers was used for estimating the terrestrial DON fraction,which was found to be about 19% and much less than the marine DON fraction in the Mirs Bay, implying that the DON was mainly from the autochthonous source. The labile DON (LDON) fraction calculated by the average ratio of the LDON: BOD5 was about 41%. The average ratio of the surface phytoplankton DON (PDON): Chl a was used for estimating the PDON fraction at about 17%, based on which in combination with the integrated DON the TDON was calculated to be about 15 days. During the 11-year study period, the LDON inter-annual variability showed a decrease trend,but both the DON and refractory DON (RDON) underwent a trend of increase,which suggested that the RDON had been gradually accumulated in the Mirs Bay.
李绪录, 张军晓, 周毅频, 夏华永, 梁佩喜. 2000~2010年大鹏湾溶解有机氮的时空分布[J]. 中国环境科学, 2013, 33(10): 1799-1807.
LI Xu-Lu, ZHANG Jun-Xiao, ZHOU Yi-Pin, XIA Hua-Yong, LIANG Pei-Xi. Temporal and spatial distributions of dissolved organic nitrogen in the Mirs Bay from 2000 to 2010. CHINA ENVIRONMENTAL SCIENCECE, 2013, 33(10): 1799-1807.
