I used small, replicated, artificial treehole habitats to determine the degree to which three factors - total volume, amount of leaf litter, and pH - affect initial colonization and subsequent growth of treehole insect larvae. I found that low leaf litter mass had to the most significant and recurring effect - densities of the common insects, Aedes triseriatus (Say), Culicoides guttipennis (Coquillett), and two helodid beetle species were higher in those microcosms. Species richness initially was higher in high volume and low resource microcosms. By the end of the experiment, densities of these insects were affected by leaf litter, pH, or their interaction. Low leaf mass attracted more helodid beetles to colonize, yet more helodids grew to a larger size in high leaf litter treatments, suggesting an interaction between oviposition preferences of females and intraspecific competition. Variation in habitats at the local scale affects communities of organisms, and inter-treehole variation is large. Between habitat dispersal and differences in resource utilization in these communities may be dependent on abiotic heterogeniety. The results indicate that treehole communities are affected by space, resource and habitat heterogeneity.
Resource heterogeneity, treeholes, microcosms, pH, aquatic insects, culicidae, ceratopogonidae, helodidae
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