MultiTroph SP3

MultiTroph Plant-arthropod food webs, stoichiometry and functions

By collecting data on community composition, consumption rates, body mass and elemental contents of arthropods as well as direct feeding links at higher trophic levels, we aim at predicting the responses of the multitrophic plant-herbivore-predator system to tree diversity loss. We specifically extend previous work by including three trophic levels (trees, herbivorous arthropods and predatory arthropods) and by linking multitrophic communities and their interactions with biomass distributions and stoichiometry to enable the analysis of trophic pyramids and energy-based networks. We will also record tritrophic species-level networks for selected tree species. We will use novel methods in the BEF-China Experiment (stoichiometry, gut content barcoding in collaboration with our Chinese collaborators) and will collect additional arthropod groups from other vegetation strata using multiple collection methods. Based on the results of previous studies, we expect that tree diversity strongly affects consumer communities in various ways and hypothesise that (1) tree diversity effects on abundance and species richness decrease with increasing trophic level and this leads -together with changes in intra- and interspecific body size distributions of herbivores and predators – to shifts in trophic pyramids along the tree diversity gradient. We further hypothesise that (2) intraspecific changes in carbon:nutrient ratios of herbivores and predators can be observed with increasing tree diversity, reflecting increased nutrient availability in plant tissues (within and across species) in more diverse plant communities. (3) Multitrophic plant-herbivore-predator energy networks are expected to show higher stocks (standing biomass) and fluxes (herbivory, predation) across trophic levels at higher tree diversity. In addition, we hypothesise that (4) structural properties of highly resolved plant-herbivore-predator networks provide more detailed mechanistic explanations of how changes in plant diversity affect ecosystem functioning.

2024-02-29

2024-02-29