Abstract: Contribution factors and enrichment factors were applied for research of the high cadmium value belt of sources in Yichang section of the Yangtze River. The result showed that the stratas in the study area made a different contribution to the high Cd-value belt, which from big to small is the Sinian system, the Permian system, the Devonian system and the Silurian system. However, the Pre-Sinian system, the Cambrian system, the Ordovician system, the Triassic system, the Jurassic system and the Cretaceous system slow down the formation of high Cd value belt. Combined study of contribution factors, enrichment factors and MapGIS spacial analyses, it showed that the major natural sources were from the processes of weathering and draining of the Sinian system and the Permian system, which are enriched of mine and cadmium. During the process of mining beneficiation, a large number of tailings and waste water were accumulated and discharged into the branch river directly, which should be the important anthropogenic pollution sources.

Key words: enrichment factor, contribution factor, high cadmium belt, pollution sources, Yichang City