Biodiversity and ecosystem functioning in stressed environments
I analyze the effects of stressors (pesticides, heavy metals) on the relation between biodiversity and ecosystem functioning. Global biodiversity is being lost at fast rates, and questions are arising how this biodiversity loss will affect functions and services that humans depend on. However, although stressors are the reason underlying the biodiversity loss, their impact on the diversity-functioning relationship is hardly investigated. I test how stressors affect the diversity-functioning relation directly (by affecting the surviving species) and indirectly (by selectively removing sensitive species) . Stressor effects on biodiversity and ecosystem functions (biomass production, energy content, reproduction, sediment stabilization) are quantified in a food web context, for the main primary producers (diatoms) and their consumers (copepods) of the Westerschelde estuary (Netherlands) . The experimental data are synthesized into a model providing in a predictive framework for biodiversity and ecosystem functioning under stress.