10. Plant Diversity in a Patchy Landscape
157
process, the studies of the two serpentine-endemic plants also illustrated the importance of deterministic factors, such as plant-pollinator interactions and habitat availability. Finally, the distance-dependent extinction and colonization found in the
study of serpentine seep plants provided good agreement with metapopulation theory
(Hanski 1997).
In terms of conservation, the results tend to support the wisdom of setting aside
large unfragmented areas to conserve maximal diversity of habitat-specialist species. The small outcrops of serpentine are more interesting from a scientific viewpoint, as places to study edge effects, ecotype evolution, and other questions relating to habitat and community structure, than they are valuable as habitats for rare
species. However, the ultimate message of this study is not that any single ecological theory or conservation tactic is universally right or wrong. Rather, the point is
that we have a great deal of work yet to do in evaluating the rich variety of ideas
provided by spatial ecology. When such theory has been examined by a substantial
number of quantitative studies at suitably large spatial scales, it may become a solid
basis for deriving conservation strategies.
Acknowledgements
This study was made both possible and enjoyable by my collaborators Paul Brodmann,
Gary Huxel, John Maron, Kevin Rice, and Amy Wolf. I also thank the many colleagues who have provided helpful advice and discussions, and the many landowners who allowed us access to the study sites. This work was supported by NSF 9424137.
References
Aizen MA, Feinsinger P (1994a) Forest fragmentation, pollination, and plant reproduction
in a Chaco dry forest, Argentina. Ecology 75:330-351
Aizen MA, Feinsinger P (1994b) Habitat fragmentation, native insect pollinators, and feral
honey bees in Argentine "Chaco Serrano" Ecol Appl 4:378-392
Barbour MG, Major J (1977) Terrestrial vegetation of California. Wiley-Interscience, New
York (reprinted 1988 by California Native Plant Society, Sacramento, CA)
Brooks RR (1987) Serpentine and its vegetation: a multidisciplinary approach. Dioscorides
Press, Portland, OR
Caswell H, Cohen 1£ (1991) Disturbance, interspecific interaction and diversity in
metapopulations. In: Hanski I, Gilpin ME (Eds) Metapopulation dynamics: ecology,
genetics and evolution. Academic Press, London, pp 193-218
Caswell, H. and J. E. Cohen 1993. Local and regional regulation of species-area relations: a
patch-occupancy model. In Ricklefs RE, Schluter D (Eds) Species diversity in ecological communities: historical and geographical perspectives. Univ Chicago Press, Chicago, IL, pp 99-107
157
process, the studies of the two serpentine-endemic plants also illustrated the importance of deterministic factors, such as plant-pollinator interactions and habitat availability. Finally, the distance-dependent extinction and colonization found in the
study of serpentine seep plants provided good agreement with metapopulation theory
(Hanski 1997).
In terms of conservation, the results tend to support the wisdom of setting aside
large unfragmented areas to conserve maximal diversity of habitat-specialist species. The small outcrops of serpentine are more interesting from a scientific viewpoint, as places to study edge effects, ecotype evolution, and other questions relating to habitat and community structure, than they are valuable as habitats for rare
species. However, the ultimate message of this study is not that any single ecological theory or conservation tactic is universally right or wrong. Rather, the point is
that we have a great deal of work yet to do in evaluating the rich variety of ideas
provided by spatial ecology. When such theory has been examined by a substantial
number of quantitative studies at suitably large spatial scales, it may become a solid
basis for deriving conservation strategies.
Acknowledgements
This study was made both possible and enjoyable by my collaborators Paul Brodmann,
Gary Huxel, John Maron, Kevin Rice, and Amy Wolf. I also thank the many colleagues who have provided helpful advice and discussions, and the many landowners who allowed us access to the study sites. This work was supported by NSF 9424137.
References
Aizen MA, Feinsinger P (1994a) Forest fragmentation, pollination, and plant reproduction
in a Chaco dry forest, Argentina. Ecology 75:330-351
Aizen MA, Feinsinger P (1994b) Habitat fragmentation, native insect pollinators, and feral
honey bees in Argentine "Chaco Serrano" Ecol Appl 4:378-392
Barbour MG, Major J (1977) Terrestrial vegetation of California. Wiley-Interscience, New
York (reprinted 1988 by California Native Plant Society, Sacramento, CA)
Brooks RR (1987) Serpentine and its vegetation: a multidisciplinary approach. Dioscorides
Press, Portland, OR
Caswell H, Cohen 1£ (1991) Disturbance, interspecific interaction and diversity in
metapopulations. In: Hanski I, Gilpin ME (Eds) Metapopulation dynamics: ecology,
genetics and evolution. Academic Press, London, pp 193-218
Caswell, H. and J. E. Cohen 1993. Local and regional regulation of species-area relations: a
patch-occupancy model. In Ricklefs RE, Schluter D (Eds) Species diversity in ecological communities: historical and geographical perspectives. Univ Chicago Press, Chicago, IL, pp 99-107