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The consequences of habitat fragmentation for plant–pollinator mutualisms

Published online by Cambridge University Press:  28 February 2007

L. Fabienne Harris  and
Steven D. Johnson
Steven D. Johnson
Affiliation:
1School of Botany and Zoology, University of Natal, P. Bag X01, Scottsville, Pietermaritzburg, 3209, South Africa
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Abstract

There is now considerable evidence for disruption of plant–pollinator mutualisms in fragmented landscapes. The causes can be myriad, and vary from lack of nesting sites for key insect pollinators, to a decline in pollinator visits when plant population sizes are reduced by fragmentation. One important and well-documented consequence of disruption in pollination systems is reduced seed production in plant populations in fragments as a result of pollen-limitation. When reduced seed production, in turn, has a negative effect on seedling recruitment, populations may enter a spiral towards extinction. Some pollination systems, on the other hand, are surprisingly resilient to anthropogenic changes, and pollen flow between trees in fragments separated by several kilometres has been reported recently. Understanding how reproductive attributes of plants, such as breeding systems and specificity of pollination systems, affect the outcome of habitat fragmentation remains a key challenge.

Keywords

Allee effectsbreeding systemextinctionhabitat fragmentationpollen flowpollen limitationpollinationpopulation size

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Type
Review Article
Information
International Journal of Tropical Insect Science , Volume 24 , Issue 1 , March 2004 , pp. 29 - 43
Copyright
Copyright © ICIPE 2004

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