Goal statement

Motivation: vital planetary functions at risk

“We emphasise the crucial importance of the conservation and the sustainable use of biodiversity as an indispensable basis for the provision of vital ecosystem services and the long term provision of natural resources for the global economy.” (G8-Summit declaration, “Growth and Responsibility in the World Economy”, issued on 7 June 2007 at Heiligendamm, Germany, based on ‘Potsdam Declaration’ made by G8 Environment Ministers in March 2007)

Ecosystems provide crucial services for people on Earth and their function is impacted by climate change. A primary and fundamental aspect of human vulnerability to climate change is whether ecosystem services (food, timber, energy, water supply, spiritual functions, recreation, etc.) can sustainably be provided in the future. Very likely, biodiversity – defined as the functional complexity of ecosystems, including genetic, species and landscape diversity – plays a crucial role for ecosystem provision capacity. A particular aspect of ecosystem function is their resilience (or capacity for autonomous adaptation) to climate change – which could be impacted by biodiversity loss due to stresses such as deforestation and other forces of degradation.

Goal: clarify the role of biodiversity for ecosystem services and assist in its sustainable use

The scientific aim of this research is to clarify the role of structural and/or functional biodiversity for the capacity of ecosystems to provide multiple services for human society under conditions of climate change. The policy-oriented aim is to help identify land use and nature conservation strategies that sustain ecosystem services. Both aims will be pursued for selected ecosystems, services and regions.

Rationale: model-based implementation of ecosystem service concept

Ecosystem services comprise provisioning (food production, timber, energy), regulative (e.g., flood control), cultural (e.g., conservation, landscape aesthetics), and supporting functions of ecosystems (e.g., genetic diversity). In its widest sense, biodiversity is a key factor for most ecosystem functions underlying these services. However current models and assessments do not take even rudimentary account of diversity at appropriate scales (genetic, species and landscape level). The Millennium Ecosystem Assessment (MA) has provided powerful illustration of the applicability of the ecosystem service concept – the scientific foundation of its findings however left many questions unanswered. Notably, the current generation of process-based ecosystem models (which include at least elementary recognition of structural biodiversity) such as LPJmL and IBIS could not be applied. Likewise, regional aspects of ecosystem-related climate change vulnerability in Germany, Europe and other regions have been assessed mostly without consideration of essential interactions between species or landscape units, despite recognition of these as important moderators or amplifiers of impacts.

Approach: assessments based on upgraded models to provide diversity-sensitive vulnerability metrics

Our general approach, pursued through the integration of a set of ongoing, collaborative studies, consists of:

• revised assessments of the vulnerability of ecosystems and their services to climate change, at different scales and in different regions with emphasis on the role of functional biodiversity (pathway analysis),
• adaptation of simulation tools (models) to quantify the impact of biodiversity on ecosystem services,
• scenario-based quantitative assessments.

The significance of biodiversity for ecosystem functions under different climate and land use change regimes is recognized in the literature (including the MA) but rarely quantified in adequate terms. For selected, policy-relevant problems in different regions (specified below), we will first identify and classify possible pathways from biodiversity to ecosystem functions. One such function is the goal of REDD (Reducing Emissions from Deforestation in Developing Countries) within the frame of the UN Framework Convention on Climate Change (UNFCCC), where associated impacts on biodiversity not only affect the climate protection targets that can be achieved but also the goals of UN Biodiversity Convention (CBD). Path-analysis can be used to make the trade-offs between the mitigation and adaptation operational and explicit, for example, if mitigation negatively impacts water relations and local biodiversity and therefore diminishes adaptive capacity of the ecosystem.

To quantify diversity-associated vulnerability, we will then review and adapt suitable metrics describing the role of diversity for climate change impacts, ranging from simple, qualitative risk assessment metrics associated with certain functions (“low, medium, high”) up to damage costs for the case of loosing vital ecosystem services. Linking the functioning of ecosystems to these impact metrics is the main challenge of biodiversity research. We expect to make progress in this direction by adding suitable functional types of plant and animal groups to existing ecosystem models, and by testing for improved model behaviour against observational data. The selection of organisms to be added will be based on the identification of candidates from the initial path-analysis.

To achieve this extension, current macro-scale ecosystem models (LPJ-family), regional forest models (4C) or eco-hydrological models (SWIM) will be complemented (through collaborative efforts, specified below) by population models, models of trophic and other interactions as well as economic models to assess and simulate function and sustainability of the most important land use types. The scale of these applications is regional to continental (Europe, Germany, Amazonia), allowing for sufficient generalisation to large regions while still being testable against observational data sets.

Organizations and public entities involved in the management of ecosystem services will be involved this process. During ongoing work, and in the concluding phases, interaction with relevant stakeholders is given high priority. Current partners for this exchange include the Umweltbundesamt, the Bundesamt für Naturschutz, BMZ, GTZ, EEA, the World Bank, DG Environment and others. In fact, several of the studies below were initiated in response to such stakeholder requests.