Home – Home – Jornals – Contemporary Problems of Ecology 2013 number 6

Quantitative studies of the population of mollusks in the herbaceous layer were carried out during the years 2006–2008 in secondary dry meadows in the gradient of pollution with the emissions from the Middle Ural Copper Smelter (Revda, Sverdlovsk Region). The number of mollusks at the territory with moderate pollution is decreased by a factor of 1,3 in comparison with the reference regions. In the direct vicinity of the smelter, mollusks in the grass stand disappear completely. The reasons of the change of the structure of mollusk population may be the toxic effect of heavy metals under the conditions of acidification of environment, the lack of available Ca due to its removal from the upper soil horizons by washing out, depletion of the species diversity and simplification of the architecture of meadow grass stand, causing modification of the hydrothermal regime in the herbaceous layer. A combination of these types of action is likely to cause elimination of the mollusks of herbaceous layer, which is not observed in the case when the environment is polluted only with heavy metals.