科研之友
微信
新浪微博
Facebook
分享链接
摘要
Sansha Bay in East Fujian is the most typical closed bay where many rivers flows into. It is the largest cage breeding base for Pseudosciaena crocea in the world and one of most important fishery breeding bases in China. However, several surveys have found that the algae production in this bay is far low compared to other bays, which presents the unique ecological characteristics of "more nutrients and less algae", but the mechanism has not been discussed in-depth. Using fixed-stations and large-scale navigation methods, in this study it investigated the tidal movement and spatial distribution of five nutrients (active silicate (SiO3-Si), nitrate nitrogen (NO3-N), nitrite nitrogen (NO2-N), ammonia nitrogen (NH4-N) and active phosphate (PO4-P)) in 2018-2020. The results show follows. (1)The upstream input causes the ebb concentration of SiO3-Si and NO3-N to be greater than the rise concentration, and they decrease linearly from the shore to the bay with salinity. (2) The aquaculture in the bay and the output of the natural ecosystem cause the rise concentrations of NO2-N, NH4-N, and PO4-P to be greater than the ebb concentrations, and the concentration in flood season is greater than that in the dry season. NO2-N increases nonlinearity with salinity from the shore to the bay instead of it is an abnormal phenomenon that NH4-N and PO4-P are evenly distributed along with the increase of salinity. However, the fall concentrations of NH4-N and PO4-P near the coastal sewage outlet are greater than the rise concentration. (3) The high concentrations of NH4-N and PO4-P imported from sewage discharge in the bay and coastal areas are the main cause of serious water pollution. Eutrophication in the Sansha Bay is the main factor of the unique ecological characteristics of "more nutrients and less algae".
-
单位华东师范大学; 河口海岸学国家重点实验室
