Sources of ecological complexity interactions between autogenous and external dynamics in an aquatic systems

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Ecology provides ample evidence that the loss of some species from ecological communities (a diversity loss) often leads to negative consequences such as the demise of other, often valuable species, changes in productivity, and the heightening of susceptibility to fire, rain, or invading species. Ecology attributes these consequences to the disruption of a complex web of relationships among species and their environment. Some links are simple: For example, the loss of pollinators will disrupt plant reproduction and lead to change in plant composition.  However, the greatest mystery is the number and effects of indirect regulatory relationships. Since they are difficult to study in isolation, ecologists have tried to capture their overall effect through a diversity-stability hypothesis.  The hypothesis predicts that more species in a community results in greater potential for regulatory relations which, in turn, lead to greater stability of ecosystems and their populations in particular. Tests of this hypothesis were successful in some experiments but failed in others.  Performing definitive tests, particularly in field situations, is difficult because the effect of diversity on the stability of communities and ecosystems may depend on confounding influences of environmental variation.  We aim to overcome this problem. Using a system of natural miniature ecosystems, each with its own community, my group intends to tease apart, by means of statistical designs and procedures, how environmental variation affects variation of populations within a community. After such statistical cleaning (that requires a whole suite of complementary activities, including using long-term data sets, experiments, digital mapping, and others), we should be able to state whether diversity plays a positive role in stabilizing population sizes and their productivity. Resolution of this question is of major importance to the discipline of ecology.  Further, it will help provide scientific understanding of the role of (bio)diversity and thus free the debate on the rationales and scope of environmental conservation from arbitrariness and political expediency.