We face “trade-offs” in everyday life from dusk till dawn. Imagine that you have to make a decision about what to have for lunch. You may have several options with a limited budget and timeframe: you could go to a restaurant spending more money and time but having a good time with colleagues, or you could go to the university cafeteria where food might be worse but you spend less money, or you could even bring food from home to have a quick lunch. At every moment, we make a decision to increase our utility knowing that we cannot have everything at the same time. Thus, we should have a comprehensive understanding of upside (gain) and downside (loss) in order to make a wise decision. The gains and losses define the trade-off between the different options: an increase in one objective leads to a reduction in another objective.
This is particularly important in natural resource management in ecosystems where decisions that you make today potentially have side effects for other systems and on future generations. To operationalise the concept of ecosystem services and to manage natural capital wisely, decision makers should ideally have a full understanding of the trade-offs of their decisions with respect to the provisioning of ecosystem services. If the increase of one ecosystem service happens directly or indirectly at the cost of another ecosystem service, an attempt to maximize the provision of a single ecosystem service might lead to sub-optimal results. To support decisions, explicit information on trade-offs between ecosystem services is therefore required.
The research on trade-offs between ecosystem services has recently gained increasing attention in the scientific community. However, a synthesis on existing knowledge and knowledge gaps was missing so far. We, Heera Lee and Sven Lautenbach from the University of Bonn, aimed to close that gap here at OPERAs via a quantitative review of the existing literature.Our analysis is based on 476 pairwise combinations of ecosystem services that have been studied in 67 case studies that report on relationships between ecosystem services.
A synergistic relationship was identified as the dominant relationship between different regulating services and between different cultural services, whereas the relationship between regulating and provisioning services was trade-off dominated. For example, when soil formation regulating service increases, habitat regulating is likely to increase (synergistic relationship). However, when crop provisioning service increases, habitat and gene pool regulating services are likely to decrease (trade-off relationship). Increases in cultural services did not influence provisioning services (“no-effect”). We further analysed the pattern of relationships between ecosystem services across scales, land system archetypes and methods used to determine the relationship. While the dominant relationship between some pairs of services changed with scale or land system archetype we did not find a general pattern of change in the relationships between pairs of ecosystem services with scale or land system archetype.
Our results provide helpful information about which services to include in ecosystem services assessments for the scientific community as well as for practitioners. Furthermore, they allow a first check if critical trade-offs have been considered in an analysis.