【作者】 李玲玲；

【导师】 陈洪涛； 于志刚；

【作者基本信息】 中国海洋大学 ， 海洋化学， 2010， 硕士

【摘要】 河口潮滩湿地是海陆相互作用的重要环境界面,其水动力作用强烈、泥沙输移和冲淤变化复杂、生物多样性丰富,具有独特的环境功能和生态价值。黄河口湿地是由黄河携带的泥沙冲淤而成,是我国暖温带最完整、最广阔、最年轻的新生湿地生态系统,其典型性强,生态环境类型独特,自然资源丰富,越来越受到国内外学者的重视。开展黄河口湿地的研究,具有重要的科学意义和应用价值。本论文以黄河口湿地表层沉积物及柱状沉积物为研究对象,分析了沉积物中总氮(TN)、总磷(TP)及间隙水中磷酸盐(PO4-P)、氨氮(NH4-N)、亚硝酸盐(NO2-N)、硝酸盐(NO3-N)、硅酸盐(SiO3-Si)的含量和分布特征,通过实验室培养法计算了营养盐在沉积物-水界面的交换通量,并结合盐度等相关参数,讨论营养盐在沉积物-水界面交换过程的影响因素,为进一步研究黄河口湿地营养盐的迁移、转化及沉积物中营养盐的再生循环提供基础数据。本论文得出的主要结论如下：(1)黄河口湿地沉积物含水率为17.14%-33.90%；沉积物中值粒径是5.4-56.21μm,各站沉积物的组成主要是粉砂,粘土和砂含量较少。沉积物含水率和中值粒径分布基本呈相反趋势,二者有较好的负相关性,说明沉积物颗粒越细,沉积物持水能力越强,沉积物的含水率也就越高。(2)黄河口湿地表层间隙水中PO4-P的含量变化范围是0.21-26.8μmol/L,平均值为2.82±4.48μmol/L。表层间隙水中NH4-N、NO2-N、NO3-N的含量变化范围分别是12.13-580.3、0.40-143.0、0.06-4464μmol/L,平均值分别为136.7±117.3、19.63±32.16、774.5±940.6μmol/L。表层间隙水中Si03-Si的含量变化范围是41.83-464.0μmol/L,平均值是111.7±86.24μmol/L。表层沉积物中TP、TN的含量变化范围分别是8.10-42.43、41.66-293.7μg/g,平均值分别为19.15±8.20、140.3±58.26gg/g。沉积物的粒度是影响TP、TN含量的重要因素,表层沉积物颗粒越细,TP、TN含量越高。(3)黄河口湿地柱状沉积物间隙水中PO4-P的含量变化范围是0.18-2.18μmol/L。在垂直分布上,PO4-P的含量基本随深度增加逐渐降低,到一定深度之后,其含量随深度继续增加有逐渐增加的趋势。沉积物间隙水中NH4-N、NO2-N、NO3-N、DIN的含量变化范围分别为4.51-348.1、0.16-130.0、1.71-2002、20.45-2314μmol/L。沉积物间隙水中无机氮的含量随深度增加基本呈现逐渐降低的趋势。沉积物间隙水中SiO3-Si的含量变化范围是59.72-256.1μmol/L。在垂直分布上,SiO3-Si含量随深度增加有逐渐增加的趋势。沉积物中TP、TN的含量变化范围分别为4.54-43.07、11.69-293.7μg/g。在垂直分布上,TP、TN的含量基本随深度增加逐渐降低,主要受到沉积物粒度的制约。(4)P04-P、NH4-N、N02-N、N03-N、Si03-Si在沉积物-水界面的交换通量分别在-0.30-0.045、-9.16-6.94、-1.20～2.10、-22.8～144、0～1.63mmol/m2/d范围内。营养盐在沉积物-水界面的交换通量受氧化还原条件及盐度影响较大。更多还原

【Abstract】 The estuarine and coastal tidal flat, as a typical transitional zone between land and ocean, is characterized by intense hydrodynamic conditions, frequent sediment transport and material exchange and high biodiversity, It has special environmental function and ecological values. The Yellow River estuary wetland is formed by the erosion of the sediment carried by Yellow River, which is the most complete, the most extensive and the most youngest new wetland ecosystem in the warm temperate of China. Because of its strong typicalness, the unique ecological environment and the rich natural resources, it attracts more and more attention of the researchers at home and abroad. Therefore, there are scientific and practical values to do research on the Yellow River estuary wetland.The paper was based on the surface sediment and the columnar sediment of Yellow River estuary wetland. The content and distribution characteristics of TN and TP in sediment and PO4-P, NH4-N, NO2-N, NO3-N and SiO3-Si in sediment pore water were discussed. Benthic exchange processes of nutrients at the sediment-water interface were measured according to the lab incubation experiments, and the influences to the exchange flux were discussed. This paper provides a basis for further research of nutrient migration, transformation and nutrient recycling in sediment of the Yellow River estuary wetland. The main conclusions are as follows:(1)The water content of sediment is 17.14-33.90%, and the median diameter of sediment is between 5.4 and 56.2μm. The main composition of sediment is silty sand, and the content of clay and sand are less. The distribution of water content of sediment and median diameter of sediment are contrary trend, and they has basic negative correlation, it means that the smaller of sediment particles, the stronger ability of sediments to hold water, and the moisture cotent of sediment are higher.(2) The concentration scopes of PO4-P in the surface sediment pore water ranges from 0.21 to 26.8μmol/L. The concentration scopes of NH4-N, NO2-N, NO3-N range from 12.13 to 580.3,0.40 to 143.0, and 0.06 to 4464μmol/L。The concentration of SiO3-Si ranges from 41.83 to 464.0μmol/L The concentration of TP and TN in sediment range from 8.10 to 42.43μg/g and 41.66 to 293.7μg/g, sediment particle size is the important influence factors to TP and TN, the smaller of sediment particles, the higher content of TP and TN. Besides, the inputs of exogenous particle nitrogen may affect the concentration of TN.(3) The concentration of PO4-P in marsh sediment pore water in Yellow River Estuary ranges from 0.18 to 2.18μmol/L. The vertical distribution of PO4-P first decreases with the depth, and then increases with the further increasing of depth.The concentrations of NH4-N, NO2-N, NO3-N and DIN in the sediment pore water range form 4.51-348.1,0.16-130.0, 1.71-2002,20.45-2314μmol/L. The concentration of inorganic nitrogen decreases with the depth. The concentration of SiO3-Si increases with the depth.The TP and TN in the sediment range from 4.54-43.07,11.69-293.7μg/g. The vertical distribution of TP and TN mainly decrease with the depth, which are affected by the sediment grain size.(4) According to the incubation experiment, the flux of nutrients between sediment and water are calculated, and factors that affect the exchange process are discussed. The results show that the fluxes of PO4-P, NH4-N, NO2-N, NO3-N and SiO3-Si between sediment and water are-0.30-0.045,-9.16-6.94,-1.20-2.10,-22.8-144,0-1.63 mmol/m2/d, respectively.The flux of nutrients are affected by salinity and redox environment.更多还原