Contents and Distribution Characteristics of Heavy Metals in Water and Sediment of Intertidalite
近海潮间带水体及沉积物中重金属的含量及分布特征

ICP-MS analytical technology was used to analyze the concentration of 13 heavy metals in surface water, pore water in sediment, suspended particulate matter, and sediment of intertidalite of Tianjin. Results show that both total amount and single concentration of heavy metals vary greatly in different media, the biggest and smallest values differ by 4 or 7 magnitudes. While the variation coefficients of the contents of total metals or single metal in the same medium are less than 0.3 and 0.5 respectively except for the pore water. The average concentration of total dissolved heavy metals is 41.2 microg x L(-1), while total contents of heavy metals in original water, pore water, sediment and suspended particles are 62.7 microg x L(-1), 112.7 microg x L(-1), 262.3 mg x L(-1) and 345.0 mg x L(-1) respectively, they are similar to inland natural river but higher then those of ocean. The composition of heavy metals in different media varied greatly, metals prone to dissolve such as Mo account for more than 20% in water, but metals uneasy to dissolve mainly exist in sediment and suspended particles and absorbed by particles. Typical heavy metals, such as Zn, Cu, Pb and Cr, account for 40% - 50% in water and 50% - 80% in other media. The similarity in distribution mode of heavy metals in intertidalite and terrestrial soil suggest that they are originated from terrestrial soil that is contiguity to the sea. Notable correlativity can be seen between concentrations of all heavy metals except for Mo in sediment, which can explain the similarity of their environmental behavior, but only wake correlation between the content of organic carbon and concentrations of heavy metals in suspended particulates and sediment.