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- Info
Patterns of plant species diversity during succession under different disturbance regimes
| Author: |
Denslow, Julie Sloan |
| Date: |
1980 |
| Periodical: |
Oecologia |
| Abstract: |
I suggest that between-community variations in diversity patterns during succession in plant communities are due to the effects of selection on life history strategies under different disturbance regimes. Natural disturbances to plant communities are simultaneously a source of mortality for some individuals and a source of establishment sites for others. The plant community consists of a mosaic of disturbance patches (gaps) of different environmental conditions. The composition of the mosaic is described by the size-frequency distribution of the gaps and is dependent on the rates and scales of disturbance. The life-history strategies of plant species dependent on some form of disturbance for establishment of propagates should reflect this size-frequency distribution of disturbance patches. An extension of island biogeographic theory to encompass relative habitat area predicts that a community should be most rich in species adapted to growth and establishment in the spatially most common patch types. Changes in species diversity during succession following large scale disturbance reflect the prevalent life history patterns under historically common disturbance regimes. Communities in which the greatest patch area is in large-scale clearings (e.g. following fire) are most diverse in species establishing seedling in xeric, high light conditions. Species diversity decreases during succession. Communities in which such large patches are rare are characterized by a large number of species that reach the canopy through small gaps and relatively few which regenerate in the large clearings. Diversity increases during succession following a large scale disturbance. |
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