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Estuarine tidal flat land and sea interaction environment interface, strong hydrodynamics, sediment transport and deposition and erosion is complex, rich in biodiversity, has a unique environmental features and ecological value. The mouth of the Yellow River wetland is carried by the Yellow River sediment erosion and deposition made of warm temperate is the most complete, the most extensive, the youngest newborn wetland ecosystem, its typical strong, unique type of ecological environment, rich natural resources, more attention by scholars at home and abroad. To carry out the mouth of the Yellow River wetland research has important scientific significance and application value. This thesis as the research object to the mouth of the Yellow River wetland surface sediments and core sediments, sediments total nitrogen (TN), total phosphorus (TP) and interstitial water phosphate (PO4-P), ammonia (NH4-N) , nitrite (NO2-N), nitrate (NO3-N), silicate (SiO3-Si) content and distribution characteristics calculated by laboratory culture through exchange of nutrients in the sediment - water interface volume, combined with salinity and other relevant parameters, discuss the factors influencing the process of nutrients in the sediment - water interface exchange, transformation and regeneration of nutrients in the sediment cycle to provide basic data for further study of the migration of the mouth of the Yellow River wetland nutrient. In this thesis, the main conclusions are as follows: (1) the mouth of the Yellow River wetland sediment moisture content of 17.14% -33.90%; sediment median diameter from 5.4-56.21μm, and stations sediments mainly composed of silt, clay and less sand content. The moisture content of the sediment and the median particle size distribution substantially opposite trends, both good negative correlation sediment particles finer sediment water holding capacity of the stronger, the higher the moisture content of the sediment. (2) water PO4-P content in the mouth of the Yellow River wetland surface gap varies in the range the 0.21-26.8μmol / L, an average of 2.82 ± 4.48μmol / L. The surface gap water NH4-N, NO2-N, NO3-N content range are 12.13-580.3,0.40-143.0,0.06-4464 mol / L, average were 136.7 ± 117.3,19.63 ± 32.16,774.5 ± 940.6μmol, / L. Surface interstitial water SI03-Si content in the range of 41.83-464.0μmol / L, the average is 111.7 ± 86.24μmol / L. Surface sediments in TP, TN content range are 8.10-42.43,41.66-293.7 microg / g the average of 19.15 ± 8.20,140.3 ± 58.26gg / g. Sediment particle size is an important factor to affect TP, TN content, the finer particles of surface sediments, the higher the TP, TN content. (3) The range of the mouth of the Yellow River wetland columnar sediment pore water PO4-P's content is the 0.18-2.18μmol / L. On the vertical distribution of PO4-P content decreases substantially with increasing depth to a certain depth, the content continues to increase with depth increasing trend. Sediment pore water NH4-N, NO2-N, NO3-N, DIN content range were 4.51-348.1,0.16-130.0,1.71-2002,20.45-2314 μmol / L. Sediment pore water of inorganic nitrogen content basically showing a trend to decrease with increasing depth. Sediment pore water SiO3-Si content in the range of 59.72-256.1μmol / L. SiO3-Si content increases with depth on the vertical distribution of a growing trend. Sediments TP, TN content varied from 4.54-43.07,11.69-293.7 μg / g. On the vertical distribution of TP, TN content of basic increases with depth gradually decreased, primarily due to the constraints of the sediment grain size. (4) P04-P, NH4-N, N02-N, N03-N, Si03-Si in the sediment - water interface exchange fluxes -0.30-0.045 of -9.16-6.94 -1.20 to 2.10, - the 22.8 ~ 144,0 ~ 1.63mmol/m2/d. Exchange fluxes of nutrients in the sediment - water interface by redox conditions and salinity influence.
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