Groundwater ecosystem services: A review.

Our daily life depends on many services delivered by the planet’s ecosystems. Groundwater ecosystems deliver services that are of immense societal and economic value, such as: 1) purification of water and its storage in good quality for decades and centuries, 2) active biodegradation of anthropogenic contaminants and inactivation and elimination of pathogens, 3) nutrient recycling, and 4) mitigation of floods and droughts. Many of these services are directly connected to the presence and activity of specific organisms, microorganisms, or metazoa. Sustainable protection and management of important groundwater ecosystem services will require quantitative understanding of processes at different spatial and temporal scales and assessment of their resistance and resilience with regard to common anthropogenic impacts. Our review compiles known groundwater ecosystem services and, where appropriate, highlights important research gaps