The role of water in ecosystems (SDG 6.6): achieving sustainable development for spring ecosystems

Here we use the state of knowledge of one of the world’s most vulnerable ecosystems—its springs—to describe key scientific, information, and policy gaps relevant to Sustainable Development Goal (SDG) 6.6. Springs are among the most biologically diverse, productive, and culturally important aquatic ecosystems on Earth. They are subsurface-surface linked, groundwater-dependent, headwater wetland ecosystems that provide the baseflow for all natural streams in nonice-dominated landscapes on Earth. Although scientific understanding of their hydrology and ecosystem ecology is improving, springs are intensively used, heavily appropriated, and globally threatened by anthropogenic factors. Although we focus narrowly here on one group of aquatic freshwater ecosystems, our approach illuminates the many gaps and uncertainties in basic science, information availability and quality, policy, and management involved in achieving SDG 6.6. We conclude with recommendations on what is needed to achieve this UN Goal and better understand and manage the world’s freshwater ecosystems, goods, services, and values.