Plant interactions in alpine tundra: 13 years of experimental removal of dominant species

Plant species responses to the removal of each of the five dominant species were studied in an alpine tundra of the Teberda reserve of northwestern Caucasus, Russia, for 13 years. While dominant plant species (Anemone speciosa Adam ex G.Pritz, Antennaria dioica [L] Gaertn., Festuca ovina L., Trifolium polyphyllum C.A. May, Carex sempervirens Vill., C. umbrosa Host. C. caryophyllea Latourr.) on the average increased the number of their shoots relative to the control after the removal of their presumed competitors, mast subordinate species in the community responded negatively to the removal of dominants. The latter group may therefore depend on the dominant plants for survival in the harsh alpine environment, and not be as much affected by competition. Most species showed consistently either negative or positive responses for the whole duration of the experiment. Experimental removal of only one species in each treatment produced a coordinated response from a number of species, which suggests presence of diffuse competition among alpine tundra plants.