Ecosystem services are important as they describe the value of nature and thus help supporting its conservation. The most popular definition by the Millennium Ecosystem Assessment (MEA 2005) is: “the benefits that people obtain from ecosystems”.
Human activities have led to the unprecedented impairment of ecosystems and their services. A number of outstanding problems concern services provided by aquatic ecosystems, including “the dire state of many of the world’s fish stocks; the vulnerability of the two billion people living in dry regions to the loss of (…) water supply; and the growing threat to ecosystems from climate change and nutrient pollution” (MEA 2005). More generally, aquatic ecosystems such as lakes, rivers or swamps provide supporting services (e.g. biodiversity or nutrient cycling), provisioning services (e.g. food such as fish or the provision of fresh water), regulating services (e.g. hydrological regimes, pollution control, or detoxification), and cultural services (e.g. spiritual or recreational; MEA 2005).
Whereas the understanding of the threats to ecosystems and the ecological benefits of conservation efforts are typically natural scientific questions, finding a balance between human activities and the protection of water resources and aquatic species is ultimately a societal problem. A social scientific approach to this issue is thus crucial.