泥沙含量和粒径对长江口杭州湾磷的形态和浓度时空分布特征影响研究

A Study on the Influence of Silt Content and Size to the Forms and Distribution Characteristics of Phosphorus in Yangtze Estuary and Hangzhou Bay

以长江口和杭州湾5个点位水样为研究对象,开展泥沙含量和粒径对磷的形态和浓度分布特征影响的实验,以获得不同粒径范围泥沙和磷营养盐的关系。研究结果表明:长江口杭州湾泥沙和总磷之间相关性显著,相关系数为0.420;5个点位泥沙比表面积介于346.10~477.65m^2/kg,中值粒径介于7.95~13.28μm,粒径50μm以下泥沙的含量百分比89.52%~97.02%;研究区域内泥沙主要为粒径<4μm的粘土及部分粒径4~63μm的粉沙,占主要质量的是粒径范围30~60μm的泥沙,整个长江口杭州湾的总磷主要携带在>15μm的泥沙上。

Water samples had been taken at five spots in Yangtze estuary and Hangzhou Bay,and the relationship between silt and phosphorus nutrients was studied by screening and grading experiments.The results showed that there was a significant correlation between silt and total phosphorus with a coefficient of 0.420.The specific surface area of silt sampled at those five spots was between 346.10 and 477.65m……2/kg with its median particle size in range of 7.95 to 13.28μm whilst the silt size below 50μm accounting for 89.52%~97.02%.Silt was composed of clay mainly in a size less than 4μm and silty sand in a size partly between 4 and 63μm.Therefore,the silt mass was mostly contributed by the particles of 30 to 60μm in size,whilst total phosphorus was mainly carried on the silt greater than 15μm.