The Yangtze River, which runs through China's several nonferrous metal rich areas, has not suffered any metal pollution, and scientists recently discovered that the river can clean itself up. Metal pollution accidents have been reported on tributaries along the lower reaches of the Yangtze in Hunan, Jiangxi and Anhui provinces, which are rich in cadmium, lead and zinc deposits, the stibium deposits in Hunan account for 48 percent of the world's total. The scientists say that when Yangtze passes through the Three Gorges area, its calcium and magnesium content rises greatly and the water is alkaline, the alkaline water then neutralizes the acid water from the tributaries in the lake.