In contrast, data from a naturally fragmented forest in India showed that fragments serve as reservoirs for tree genetic diversity. Rajani Kanth of the University of Agricultural Sciences, Bangalore, presented work with collaborators B. Tambat, G. Ravikanth, U. Shankaar, and K.N. Ganeshaiah, demonstrating that although individual small fragments of shola forest in the Western Ghat mountains are low in genetic diversity, collectively they contain more diversity than large fragments, emphasizing the value of small fragments for conservation.

Jean Paul Metzger of the Universidade So Paolo, Brazil, reported on studies of the effects of fragment size and connectivity on species survival, community richness, and regeneration processes in the Atlantic forest of Brazil. Detailed surveys of trees, vertebrates, and butterflies showed fragmentation affected species richness and diversity for all study groups, and also affected important ecological processes, but some of these effects were unexpected. For example, tree communities in small isolated fragments turned out to be richer in than those in larger connected ones.

Surrounding land use can have important effects on species persistence in fragmented landscapes. Luis Miguel Renjifo of the Insituto Alexander von Humboldt, Colombia, compared the relative abundances of 113 species of birds in forest fragments surrounded by either pastures or exotic tree plantations, to those in plots surrounded by continuous forest. More than 65% of the species showed significant differences in abundance depending on the surrounding type of land use. Some species persisted better in patches surrounded by plantations than in those surrounded by pasture, suggesting that such a land use could be used as a management tool as a complement to habitat protection and restoration.

Future climate change due to global warming may have catastrophic
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Contact: William F. Laurance
laurancew@tivoli.si.edu
011-507-212-8252
Smithsonian Tropical Research Institute
1-Aug-2002