The effect of cement factory air pollution on thermophilous rocky grassland

Abstract

The thermophilous communities of calcareous rocky slopes in Radotín Valley are rather stable and present a species composition very similar to that described by Domin (1928). Some changes in their structure may nevertheless be observed due to the changing complex of human impact. The worst influence in the last 20 years is the air pollution of a cement factory. The following changes were observed on permanent plots at various distances from the source of pollution:

• 1. Complete disappearance of a number of species.

• 2. Decrease in frequency of other species and increase of frequency of a few of the most resistant species, occupying the free niche.

• 3. Decrease in cover of the entire community.

• 4. Acceleration of soil erosion, disintegration of the soil profile, enormous accumulation of Ca cations accompanied by decrease of many other mineral elements.

These results show that the effect of cement factories on the environment should not be underestimated in comparison with more serious damage caused by other air pollutants.

I am grateful to Dr. B. Holubičková for help with statistical analyses; to Ing. J. Haleš, PUDIS, Praha, for chemical analyses of soil samples; to D. Osborn for improving the English of my translation.

Nomenclature follows Oberdorfer (1970)