Print PageMetacommunity theory considers how local and regional spatial scales are connected by dispersal. A metacommunity framework can be used to understand patterns of beta diversity, or the change in species diversity across spatial scales. Theory predicts that increasing dispersal rates will decrease beta diversity within a metacommunity, but little work has been done documenting the influence of dispersal on beta diversity in natural systems. I used pond surveys to evaluate the effects of landscape characteristics on patterns of beta diversity for organisms with varying dispersal abilities. During the summers of 2009 and 2010, seventy-two fishless ponds from thirteen different aquatic metacommunities in Missouri were sampled for zooplankton, macroinvertebrate, and amphibian species richness. Permutation tests were used to determine if metacommunities had unique species compositions. Sampled organisms were classified according to dispersal ability and beta diversity metrics were calculated for each metacommunity. Landscape variables that could affect beta diversity of different types of dispersers were also calculated for each metacommunity, and the effect of these landscape variables on beta diversity was investigated.
Results/Conclusions
Metacommunities have unique species compositions for all groups of sampled aquatic organisms. Additionally, there is variation in the amount of within-metacommunity beta diversity. Analyses grouping organisms by dispersal mode explain different patterns of beta diversity across metacommunities. Communities of larval odonates and zooplankton experience a decrease in beta diversity in metacommunities where ponds are less isolated, which matches the theoretical expectation. However, communities of comparatively poor dispersers do not experience a change in beta diversity with pond connectivity. Results of this study indicate that organisms with different dispersal abilities contribute to different patterns of metacommunity beta diversity.
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