Ecology of cliff ecosystems

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My past research has shown that cliffs are among the most ignored but interesting habitats on earth. They hold ancient plant and animal communities, they tell us about the changes in the earth's climate, and they represent one of the primal habitats that early humans depended on for their survival. Here I present a new research plan that takes advantage of my discoveries about the ecology of rock outcrops, and applies that knowledge to new questions about how environmental heterogeneity and disturbance independently organize biological systems.  These new questions are important to ask since vegetation management plans for cities and wilderness alike hinge on understanding the forces that disrupt natural systems and invite alien plants & animals to invade.  Many researchers are currently interested in the role of environmental heterogeneity and disturbance, but I believe that most of these people are working on the wrong kinds of systems.  Highly productive & species rich systems are unlikely to be useful because they are simply too complicated to experiment with. By contrast, rock outcrops systems have low productivity and low species richness and hence the forces that control biological community structure can be more readily controlled in field studies & experiments.  I will begin the new work by conducting the first-ever meta-analysis of published data to discover the degree to which heterogeneity and disturbance have been separated in past work. I suspect from my preliminary work that they have not been separated at all.  Next I will use several of my long term study sites that included microsites that are variously exposed to heterogeneity and disturbance, to uncover the degree to which one or the other set of forces regulates plant growth in the field.  Then I will conduct experiments at some abandoned quarries to discover the degree to which spatial heterogeneity versus biomass-removing disturbances influence the subsequent development of vegetation.  Lastly, we will examine the degree to which rock outcrop plants that dominate cities respond to microhabitat variability as opposed to biomass-removing disturbances.  All of this work will add great value to our understanding and management of the natural environment.