Chen Jingsheng, Zheng Chunjiang, Gao Guangshing, Cheng Chengqi
The basic environmental geochemical characteristics of suspended mattel and sediments in five main rivers—the Hailongjiang River, the Songhua River, the Huanghe River, the Changjiang River and the Zhujiang River—in east China studied by the authors include followings: the physical composition of suspended matter and sediments, the composition and properties of organic matter and clay manirals, the ion exchange capacity of suspended matter and sediments, the adsorptive power of Cd, and the contents of various elements in suspended matter. The results show that controlled by the geographic and geological conditions in basins of the rivers mentioned above, the environmental geochemical characteristics present specific differential rules. 1) The sequence of contents of clay particles (<0.005mm) in sediments is the Changjiang River>the Heilongjiang River>the Huanghe River>>the Zhujiang River>the Songhua River; in suspended matter is the Zhujiang River≥the Songhua River>the Changjiang River>>the Huanghe River. 2 ) The ratios of K/M (K:Kaotinite, M:Monlmorittonite), E4/E6 (E:Optical density of humic acid),H/F (H:Humic, F:Fulvic) increase gradaully from north rivers to south ones. 3) The cation exchange capacity and adsorptive power of Cd on the bulk sediments, clay particles and humic matter are higher in north rivers than that in south rivets. 4) Qm K(both are characteristic value of adsorption isotherm) and other parameters show that the adsorptive power of sediments and suspended matter for the heavy metals is ions the largest in north rivers. 5) The concentration of most trace metals, such as Cu, Pb, Zn, Cd, As, Hg in the suspended matter are the highest in the Zhujiang River. One of the reasons is that many large metalliferous ores distribute on the Zhujiang River basin.