Abstract:

 The results of the multipurpose geochemical investigation in China, which is still in progress, show that Cd geochemical anomalies are spreading through the whole Yangtze River valley Reasonably, the origin of the anomalies and Cd output fluxes for the major tributaries of Yangtze River have become key points of scientific studiesThe water system in the source area of Yangtze River includes Tongtian River as well as tributaries of Togton River, Qumar River, Gar Qu, Bi Qu, Dam Qu, Kouqian Qu and Nyaqa Qu The geochemical mapping has been performed with dense sampling of stream sediments at 1 sample/km2, and a giant CdPbAs geochemical province and a Cd province have been outlined in the basins of Togton RiverGar Qu and the Za QuNyaga Qu  respectively, whereas for the rest of the area just show normal background of Cd, Pb and AsIt has been found out through the study that the contents of Cd, Pb and As in the rocks in the Togton RiverGar Qu geochemical province of Cd, Pb and As are significantly higher than those in soils and stream sediment, showing that a large amount of Cd, Pb and As were released to water bodies during the forming of soils and stream sediments by weathering The contents of Cd, Pb and As in the raw water of the trunk stream of Tongtian River are 0144, 1762 and 259 μg/L, respectively; while they are 0187, 1998 and 233 μg/L for the raw water of Togton River and 0144,637 and 233 μg/L for the raw water of Nyaga Qu, respectively They are almost one order higher than those for the rest of tributaries, indicating that the contents of Cd, Pb and As have been controlled by geological processBased on calculations, the year outputs of Cd, Pb and As from the Togton River to Tongtian River are 0155, 1647 and 193 t, respectively, while they are 0015, 077 and 035 t from Qumar River to Tongtian River, 0095, 1031 and 272 t from Gar QuBi Qu to Tongtian River and 248, 2907 and 423 t from Tongtian River to Jinsha River, respectively All these show that the Cd geochemical province in the source area of Yangtze River is an important material source of Cd geochemical anomalies along Yangtze River Analytical results of the raw water and the filtered water (by using 045 μm filtering film) indicate that the migrations of Cd and Pb in the water body in the source area of Yangtze River have been mainly in the form of suspended substances, whereas for As it has been in the form of soluble substances

Key words:

Key words: Cd geochemical province; the year outputs; the source area of Yangtze River