Access

You are not currently logged in.

Access JSTOR through your library or other institution:

login

Log in through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Beta Diversity on Geographic Gradients in Britain

Susan Harrison, Sally J. Ross and John H. Lawton
Journal of Animal Ecology
Vol. 61, No. 1 (Feb., 1992), pp. 151-158
DOI: 10.2307/5518
Stable URL: http://www.jstor.org/stable/5518
Page Count: 8
  • Read Online (Free)
  • Download ($18.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Beta Diversity on Geographic Gradients in Britain
Preview not available

Abstract

1. We measured beta diversity, or turnover in species composition, in each of 15 taxa (including plants, vertebrates and invertebrates), along two common transects: N-S and W-E arrays of 50X50 km squares across Britain. Comparing taxa, we asked whether high beta diversity is associated with poor powers of dispersal. Within taxa, we asked whether turnover increases consistently with geographic distance. 2. Beta diversity on this scale was found to be low in all groups. Total (transect) species richness increased by only 3-13% per 50X50 km square, relative to the average value of local (within-square) richness; or by 0.6-6% per square, relative to the maximum value of local richness. Among taxa, beta diversity showed no tendency to be higher in poorer dispersers. 3. In nearly all taxa, beta diversity as defined by Whittaker (1960) increased linearly with distance on the N-S transect. However, this was shown to be largely the effect of gradients in alpha (local, within-square) diversity. Moreover, distance is highly correlated with environmental (climatic) dissimilarity, providing an alternative explanation for distance effects. 4. We conclude that in the British biota, turnover at this scale is more the product of range and habitat restriction than of dispersal limitation; and that turnover is a relatively minor component of regional diversity, because of the predominance of strong gradients in alpha diversity.

Page Thumbnails

  • Thumbnail: Page 
151
    151
  • Thumbnail: Page 
152
    152
  • Thumbnail: Page 
153
    153
  • Thumbnail: Page 
154
    154
  • Thumbnail: Page 
155
    155
  • Thumbnail: Page 
156
    156
  • Thumbnail: Page 
157
    157
  • Thumbnail: Page 
158
    158