Transport and distribution of nutrients in anchovy spawning ground to the southern waters of Shandong Peninsula

INTRODUCTIONNutrients (N ,PandSi)areessentialforphytoplanktongrowthinmarineecosystem .Thetransportandcycling ,distributionandvariationofnutrientsaffectnotonlyonthestructureandfunctionofecosystem ,butalsoonthevariationofthebiologicalresourcesinthesea .ThesouthofShondongPeninsulaisoneofthecentralzonesofurbanandagriculturalactivities.Al thoughthereisnodirectlargeriverinput,seasonalvariationofchemicalenvironmentisobviousintheHaizhouBay .Inspringandsummer,thedistributionsofnutrientsareinflu…

Transport and distribution of nutrients in anchovy spawning ground to the southern waters of Shandong Peninsula

The distribution of nutrients and the effect of side transport of nutrients on anchovy spawning ground to the southern waters of Shandong Peninsula are discussed based on the data collected in June 2000, May and June 2001. The coastal current and upwelling are the main physical processes of nutrient transport to the southern waters of Shandong Peninsula. The concentrations of nutrients, Chla, the density of anchovy eggs, larva and juvenile fish increase obviously where they are greatly affected by these processes, while the contents of nutrients and Chl-a, the density of anchovy eggs, larva and juvenile fish decrease significantly where these processes diminish or disappear. The investigation suggest that the side transport of nutrients by Lubei (North Shandong) coastal current in the northern area causes the Chl-a content to be high and dense anchovy eggs, larva and juvenile fish to be dense in the coastal area of the Chengshan Cape. In the southern area, the riverine input from Subei irrigation ditch with high content of nutrients inshore and upwelling in the western edge of the Huanghai Sea Cold Water offshore should be responsible for high Chl-a concentration and dense anchovy eggs, larva and juvenile fish.It is possible that these processes of nutrient transport have controlled the anchovy spawning ground to the southem waters of Shandong Peninsula.