Disentangling direct and indirect effects of experimental grassland management and plant functional-group manipulation on plant and leafhopper diversity

摘要: Plant biodiversity can affect trophic interactions in many ways, including direct bottom-up effects on insects, but is negatively affected by agricultural intensification. Grassland intensification promotes plant productivity, resulting changes community composition, and impacts higher levels. Here, we use a novel grassland management experiment combining manipulations of cutting fertilization with experimental functional group composition (independent effects) to disentangle the indirect insect herbivore diversity abundance. We used leafhoppers as model organisms they are key taxon grasslands react rapidly changes. Leafhoppers were sampled between May September 2010 using standardized sweep netting pan traps. diversity, regime leafhopper species richness Higher frequencies directly led decreasing richness, presumably due disturbance frequency reduction food-resource heterogeneity. In contrast, fertilizer application had only small negative effect via enhanced aboveground biomass, reduced composition. The manipulated increase grass cover contrasting richness: increased which turn was positively related richness. conclusion, driven complex ways management, availability preferred food sources important drivers interacting resource