Beta diversity of plant-insect food webs in tropical forests: A conceptual framework

Abstract

1.Beta diversity of plant-herbivore food webs, defined as turnover of trophic interactions between the food webs, represents a potentially useful extension of traditional studies of plant and herbivore beta diversity as it integrates spatial turnover of plant and herbivore species with changes in herbivore host plant preferences. 2. Beta diversity of plant-herbivore food webs can be partitioned into four components,corresponding to the turnover of plant-herbivore interactions due to change in (i) both plant and herbivore species, (ii) plant, but not herbivore, species, (iii) herbivore, but not plant, species, and (iv) herbivore host preferences between food webs. These components can be quantified using a range of existing beta diversity indices. 3. Relative magnitude of plant and herbivore beta diversity of plant-herbivore food webs can be analysed as an outcome of herbivore (i) host specificity, (ii) ability to track Vojtech host plant populations by dispersal, and (iii) response to environmental conditions, competitors and enemies. The relative importance of these factors in tropical ecosystemsremains to be determined. © 2008 The Author.