Commonness and rarity in plants with special reference to the Sheffield flora part II: The relative importance of climate, soils and land use

Abstract

Although the flora of the Sheffield region was initially shaped by climatic and edaphic forces, at this present time land use appears to be by far the most significant determinant of the commonness and rarity of individual species. Differences between major habitats of the region with respect to their proportion of rare species (aquatic > mire > woodland > grassland > open habitats > arable) can be attributed simply to differences in the vulnerability of the vegetation of the various habitats to changing patterns of land use. The greater levels of fertility and disturbance associated with modern land use is resulting in the creation of a new flora with the replacement of communities of stress-tolerant species ( sensu Grime, 1974) by those with competitive or ruderal strategies. These changes, apparent in the Sheffield region, are probably an accurate reflection of those which are occurring within Britain as a whole.