Ecological models for evaluating the future of nature values and ecosystem services

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Photo: CTFC

New study on evaluating the future of nature values and ecosystem services in Mediterranean forests sheds light on the best use of predictive tools to inform decision-making for conservation in the context of global change

Science and society are increasingly interested in predicting the effects of global change and socio-economic development on natural systems, to ensure maintenance of both ecosystems and human well-being. The Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) has recently identified the combination of ecological modelling and scenario forecasting as key to improving our understanding of those effects, by evaluating the relationships and feedbacks between direct and indirect drivers of change, biodiversity, and ecosystem services.

This study reviews the available literature on the use of ecological models to predict environmental impacts of global change, to answer the following questions: (1) what are the modelling approaches most commonly used to predict the condition and trends of biodiversity and ecosystem services under future scenarios of global change? (2) what are the drivers of change considered in future scenarios and at what scales? (3) what are the biodiversity/nature and ecosystem services indicators most commonly evaluated? The review focuses on the case study of Mediterranean forests. These are biodiversity-rich, complex socio-ecological systems that have been continuously adapting to human use and exploitation throughout many centuries while providing important services and goods to society. Thus, future conservation of these systems must deal with multiple cultural, ecological and economic values, and complex dynamics of social change are likely to be exacerbated by global change.

The review shows that forecasting studies in the context of Mediterranean forests make relatively little use of modelling approaches accounting for actual ecological processes and feedbacks between different socio-ecological sectors; predictions are generally made on the basis of a single (mainly climate) or a few drivers of change, with some drivers of change barely represented (e.g. invasive species, pollution). In general, there is a bias in the set of nature and ecosystem services indicators assessed: while most studies focus on provisioning (e.g. timber production) and regulating services (e.g. carbon sequestration), cultural services and indicators of human well-being are greatly underrepresented in the literature. The review shows an imbalance in the information available across the North-South and West-East axes of the Mediterranean, making it difficult for the scientific community to make robust predictions of future global impacts at the level of the whole Mediterranean basin, especially for its southern part. In the publication, we argue that all these shortfalls hamper our capacity to make the best use of predictive tools to inform decision-making for the conservation of Mediterranean forests in the context of global change.

Ref. Morán-Ordóñez, A., Roces-Díaz, J.V., Otsu, K., Ameztegui, A., Coll, L., Lefevre, F., Retana, J., Brotons, L. (2018) The use of scenarios and models to evaluate the future of nature values and ecosystem services in Mediterranean forests. Regional Environmental Change (early online). DOI: 10.1007/s10113-018-1408-5