Details zur Publikation
|Titel (primär)||Do nutrients and invertebrate herbivory interact in an artificial plant community?|
|Autor||Schädler, M.; Rottstock, T.; Brandl, R.|
|Journal / Serie||Basic and Applied Ecology|
The addition of nutrients has been shown to decrease the species richness of plant Communities. Herbivores feed on dominant plant species and should release subdominant species from competitive exclusion at high levels of nutrient availability with a severe competitive regime. Therefore, the effects of nutrients and invertebrate herbivory on the structure and diversity of plant communities Should Interact. To test this hypothesis, we used artificial plant communities in microcosms With different levels of productivity (applying fertilizer) and herbivory (adding different numbers of the snail, Cepaea hortensis, and the grasshopper, Chorthippus parallelus). For analyses, we assigned species to three functional groups: grasses, legumes and (non-leguminous) herbs. With the addition of nutrients aboveground biomass increased and species richness of plants decreased. Along the nutrient gradient, species composition shifted from a legume-dominated Community to a community dominated by fast-rowing annuals. But only legumes showed a consistent negative response to nutrients. while species of grasses and herbs showed idiosyncratic patterns. Herbivory had only minor effects. and bottom-up control was more important than top-down control. With increasing herbivory the biomass of the dominant plant species decreased and evenness increased. We found no interaction between nutrient availability and invertebrate herbivory. Again. species within functional groups showed no consistent responses to herbivory. Overall. the use of the functional groups grasses, legumes and non-leguminous herbs was of limited value to interpret the effects of nutrients and herbivory during our experiments. (C) 2007 Gesellschaft fur Okologie.
|Schädler, M., Rottstock, T., Brandl, R. (2008):
Do nutrients and invertebrate herbivory interact in an artificial plant community?
Basic Appl. Ecol. 9 (5), 550 - 559