Distribution Characteristics, Influential Factors And Pollution Assessment Of Nitrogen And Phosphorus In Surface Sediments Of Xiangshan Bay

Xiangshan Bay is the biggest marine aquaculture base in Zhejiang province, after years of fast development. As the breeding quantities growing, the eutrophication degree of the water body increased, and frequency of red tide occurring also increased. All of this resulted in great losses to the fish breeding industry. As important source and sink of N and P, sediments should be able to record the changement of N and P, and analysis of the distribution pattern and pollution assessment of N and P in the sediments is imperative.Based on surface sediment samples acquired in May and November, 2005, from Xiangshan Bay and two intertidal zones which were in main breeding areas, the spatiotemporal distribution patterns and influential factors for nitrogen and phosphorus, including inorganic nitrogen (IN), organic nitrogen (ON), total nitrogen (TN), inorganic phosphorus (IP), organic phosphorus (OP) and total phosphorus (TP) are analysed, and environmental quality assessment for the Xiangshan Bay are discussed, in the hope that, they can provide some scientific insights for the local government in developing acquiculture and environmental planning and management.Studies showed that, samples acquired in Nov. have higher concentrations of different forms of N and P in the surface sediments for Xiangshan Bay and intertidal zones than that of May. Sea-water aquiculture, seasonal continental runoff input, and the distribution of marine plankton are main reasons for the seasonal variations of N and P.Concentrations of different forms of N and P in the surface sediments...