Аннотация:Gigon (1987) suggested that in the alpine zone, environmental factors may play a leading role in excluding certain plant species from the less productive habitats (e.g., alpine heaths), while interspecific competition may play a more important role in the more productive habitats, e.g., in the alpine grasslands and meadows. Despite some recent contributions to the assessment of the relative importance of biotic and abiotic factors along productivity gradients (Grace 1993, Keddy et al. 1994, Wilson & Tilman 1995, Goldberg & Novoplatsky 1997), Gigon’s hypothesis has not been tested with direct experiments.