Research on Distribution Pattern of Heavy Metals in Yanzhou Coalfield

Heavy metal pollution brings extensive concerns since 1940s. In order to assess the heavy metal pollution on the farmland of Yanzhou coalfield, 216 soil samples and 54 combined samples were collected. Lead, cadmium, chromium, copper, zinc, and nickel contained in both topsoil and deep soil were analyzed using atomic absorbent spectrometry analyzer （AAS）. Fuzzy clustering method was used in data processing. And fuzzy synthetic assessment was applied to assess the soil contamination by heavy metals. The result shows that Yanzhou coalfield has been polluted by the heavy metals to some extent.