Early succession on plots with the upper soil horizon removed

Succession was studied on plots with the upper soil horizon removed in an a rea affected by acidic air pollution in the Krusne Hory Mts., Czech Republi c. 10 permanent 1-m(2) plots were marked and vegetation recorded annually u sing a grid of 100 subplots from 1989 to 1995. Constrained ordination analy ses showed that soil texture is the most important environmental factor inf luencing the course of succession. Its effect on species composition increa ses with successional age of the plant community. On fine-grained soils spe cies-poor communities dominated by grasses (Calamagrostis villosa, Deschamp sia flexuosa) and on coarse-grained soils species-rich communities dominate d by heather (Calluna vulgaris) developed. Succession proceeded from commun ities where species composition was determined by diaspore availability tow ards communities where species composition depended on environmental condit ions. Successional communities after 10 yr are mon dependent on soil charac teristics and consequently environmental determination increases over the c ourse of succession and causes the communities to diverge.