Ecosystem functional diversity and services
Life together with climate and other abiotic drivers is the basis to the state and functioning of the ecosystems. Although we do not fully understand the entirety of consequences of our doing, humanity is exploiting, in many places over-exploiting, ecosystems around the world: to gather resources, as space for human living, and for agriculture, forestry, and many other forms of use. Biodiversity and plant and animal communities are impacted by land-use change and climate change in a complex way that is not trivial to understand or yet predict. But likewise, we do not yet fully understand the consequences of changes in biodiversity for ecosystem functioning (including, for instance, consequences for climate regulation). Which is why we need to push the boundaries of our knowledge to help decision makers to steer actions towards using our ecosystems in a sustainable way and to apply appropriate climate change mitigation and adaptation measures as well as Nature conservation in an integral way.
We use the dynamic global vegetation model LPJ-GUESS to explore ecosystem functioning, which are indicative for important services ecosystems provide to humans, and changes therein that are caused by changes in land use and management, climate change. We investigate ecosystem services related to the productivity and carbon sequestration potential of ecosystems (e.g. net primary productivity, vegetation C, soil and litter C), agricultural production (e.g. crop yield production, N leaching) and the water cycle (e.g. total water runoff, evapotranspiration). A special focus lies on the ecosystem responses to future land-use options that may include climate adaptation and mitigation options (e.g. production of bioenergy with carbon capture and storage, or avoided deforestation and reforestation or afforestation).
Another focus of our work lies on the driving role of animals in terrestrial ecosystems and their interactions with the ecosystems’ functioning and productivity. We seek to quantify both direct effects of herbivory (e.g. removal of vegetation biomass) and indirect effects (e.g. changes in plant species composition, regulation of fire frequency and intensity). Eventually we are interested to quantify the cascading effects of higher trophic levels in forms of top-down regulation on herbivory (e.g. absence/presence of apex predators, die-offs of animal functional groups) on ecosystem functioning. To do so, coupled the DGVM LPJ-GUESS with a model of heterotrophic populations (model: Madingley).