Heavy metal content in animal body and its relations with soil and water in the Zhengjia small cave, Guizhou Province

In this paper, cave animal and heavy metal pollution in Zhengjia small cave in Anshun City, Guizhou Province is studied. The collected samples is 551, belonging to 3 phyla, 6 classes, 10 orders,20 families and 29 groups. The content of heavy metals in 5 groups of animals(snail, diplopod, Diestrammena marmorata ,bat guano and Orthomorpha) and that in the soil and water in cave is determined, and the accumulation coefficient of all animal groups and pollution index of soil in cave is studied. The results show that contents of Zn in bat guano（670.5 mg/kg） is the highest, inferring indirectly the pollution of Zn in the environment around the cave is more serious. Diplopod has not accumulation ability to Ni and Diestrammena marmorata has not accumulation ability to Cr and Ni too. The average contents of all elements in the soil with light belt, dim light belt and dark belt exceed the background value of soil in China, ordering as Zn＞Ni＞Cu＞Cr＞Pb＞As＞Hg＞Cd, and Zn＞Cr＞Ni＞Cu＞Pb＞Hg＞As＞Cd in water body. The single pollution index shows that Hg, Ni and Zn pollution are severe in the soil, averaging 5.11, 3.18 and 3.02 in light belt, dim light belt and dark belt respectively. The average of comprehensive pollution index (2.17) shows that the pollution is light in light belt, dim light belt and dark belt, which means that this cave has been polluted by heavy metal, but not seriously.