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Nutrients in the ocean is an important chemical material basis for the development of the productivity of the water, which the lack of any kind of elements are likely to become the limiting factor in the growth of plankton, nutrients in seawater has been one of the hotspots of marine research. East Yellow Sea area focus on the content and distribution of the biogenic elements, sea biogenic elements of external complementary mechanisms and the inner loop mechanism should be explored. Of this paper is to understand the East Sea, Yellow Sea and nutrient distribution, determined by the method by laboratory culture method and the diffusion flux of sediment - water interface nutrient exchange fluxes of interface exchange process for the sea nutrients contribution explore of Sanggou Bay nutrient status and estimated the sediment - water interface nutrient diffusion flux, provide basic science to the East, the migration of nutrients in the Yellow Sea, the conversion process and the establishment of nutrient recycling model basis. October 2006 - 2007 April 4 voyage on the Yellow Sea and East Omo and representative cross-section of the survey results show that the nutrient content and distribution of the sea obvious regional and timeliness. Yellow Sea, in the fall of 2006 voyage that the the NO 3 - the PO 4 3 - , SiO 3 2 - , DIN, TDP, TDN concentration has a similar distribution characteristics, the highest surface to the Yellow Sea southwest and decreasing rapidly from south to north and north-east direction, south of the Yellow Sea northeastern content of the lowest; increase from west to east gradient in the underlying content is higher in the southern part of the investigation waters, DIN NO 3 - . The central region of the Yellow Sea cold water mass affect the existence of significant thermocline stratification of the dissolved nutrients are more obvious; Spring 2007 voyage rapid propagation of the central South Yellow Sea waters value phytoplankton blooms of phytoplankton so that the nutrient content at a low level and growth; spring the Huanghai upper water body starts warming, serials station significantly stratified temperature distribution, each of dissolved nutrients in the stratification phenomenon is more obvious, the surface and bottom of nutrient concentrations were quite different. Several river systems of the East China Sea, the Kuroshio surface water, the Kuroshio subsurface water Kuroshio intermediate water shelf mixed water interactions, control of the East China Sea continental shelf nutrient distribution and composition. Autumn and winter, two cruise trend of the distribution of nutrients is very similar to the high content of nutrients in the surface layer of coastal waters in the East China Sea, since decreasing outward Nutrients fast, low value area of ??the central and southeastern waters of the entire area for nutrients. Underlying nutrient distribution and surface is the same, but in addition to the the coastal high value outside, close to the open sea near Okinawa Trough is also a high value distribution. Due to the continental shelf water vertical mixing intense, more uniform temperature, salt and various nutrients distribution of surface and bottom nutrient concentrations in the shelf is substantially perpendicular to the same, but with the increased salinity is decremented by the near-shore open sea. East Sea, Yellow Sea sediment - water interface in nutrient exchange fluxes were investigated in laboratory culture results show that the form of the rate of diffusion of nutrients and the presence of nutrients, sediment type, sediment redox environment and organic matter content and many other factors, most of the survey area sediments the NO 3 - , the Po 4 3 - TDP, SiO 3 2 - exchange the NH 4 , DIN, Don's source; With rich Nutritious Level increases, Si as the possibility of community structure of control factors gradually increased, the Si diffusion from the overlying water to the sediment and DIN diffusion from sediment to seawater may further enhance the nutrient structure of this imbalance. The results calculated by the sediment pore water nutrient concentration gradient as a whole is less than the laboratory culture method, the two methods resulting PO43-diffusion flux more consistent. Compared with other surveys on the waters in the world, the East Sea, Yellow Sea sediment - water interface nutrient exchange fluxes in the medium level. With April 2006, July, November and January 2007, four cruise Sungo Bay waters, the distribution of nutrients in the waters, the structure, the main control process, and sediment - water interface diffusion through The amount was discussed. The results showed that the waters Nutrient distribution obvious seasonal variation, NO3 - N, NO2 - N, PO , 4 3 - , DOP, TDP and SiO 3 2 - are highest in autumn, NH4-N, Don TDN content was highest in summer; except DON, the minimum value of the nutrients in the spring. A large number of low concentration of nutrients and large algae kelp growing season as well as the growth and reproduction of phytoplankton consumption. Analysis of nutrient stoichiometric limit the minimum threshold standards and the growth of phytoplankton, P spring, the limiting factor for phytoplankton growth summer Sanggou Bay; estimate Sanggou Bay sediment - water interface diffusion flux results show Sanggou Bay sediment release of NH4 PO43-and SiO , 3 2 - small contribution of primary productivity compared to other shallow water environments, Bay sediments Sanggou - water interface nutrient fluxes in the lower or middle level.
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