SUMMARY (1) Interspecific competition between thirteen populations of eight species characteristic of sea-cliff vegetation was studied over a 3-year period. The investigation permitted the ranking of the species in order of their relative dominance and suppression under the experimental conditions. Festuca rubra, Armeria maritima and Agrostis stolonifera were found to be the most competitive species. (2) A similar study examined only ecotypes of one species (Armeria maritima). Of the eight populations, one died early in the 4-year study period, but the remaining seven could be ranked in order of their survival, vigour and interspecific competitiveness. Inland lowland populations of ssp. elongata, montane and lowland populations from Donegal, and shingle populations from Norfolk performed best; sea-cliff populations from Skye and Caithness and salt-marsh populations from Norfolk were least vigorous under experimental conditions. (3) The ecological significance of relative vigour between populations within a species and interspecific competition between several species in a community is discussed. The eight species studied are shown to have a high ecological combining ability, whereas the different populations of Armeria maritima have a low ecological combining ability. The former have apparently adapted either to co-exist or to utilize more fully the resources of the environment, whereas the latter have adapted to local conditions.
No takes yet. Share an insight, caveat, or question.
F. B. Goldsmith (1978) studied this question.