Groundwater is a crucial source of water that underpins, supports, or sustains entire habitats and biocoenosis, ranging from wetlands, riparian zones, caves, aquifers, springs, forests, grasslands, and coastal environments. Conversely, ecosystem processes can significantly influence groundwater quality and dynamics. These interactions involve a diversity of ecological and hydrological processes such as groundwater uptake by vegetation, stream–aquifer exchange, biogeochemical reactions in aquifers, bioturbation by groundwater resident fauna, and soil–plant–atmosphere interactions. As these feedbacks are tightly connected to land surface, GDEs can be highly sensitive and vulnerable to anthropogenic pressures such as land use (change), water withdrawal, and climate change. Conversely, GDEs can provide important buffering capacities to environmental variability and extremes, and present important forms of Nature-based solutions. Further, GDEs often support human activities, from supporting pastoral livelihoods to underpinning cultural values. Thus, understanding groundwater-ecosystem interactions is not only important for the field of ecohydrogeology, but moreover to inform management policies and strategies that holistically integrate ecological, hydrological, and social outcomes. This session seeks contributions that: highlight the role of groundwater in sustaining ecosystems; examine the impacts and feedbacks linking diverse ecosystem processes with groundwater quality and quantity; the detection and delineation (i.e., mapping) of GDEs across local to global scales; and introduce of new methods to analyze interactions between groundwater and dependent ecosystems. Submissions that advance data acquisition methods; local-scale in-situ studies; empirical data analysis; ecohydrogeological model simulations; scaling of processes and their detection from the plant to regional scales; the resilience of GDEs and their connected systems; socioeconomic and cultural interactions and meanings of GDEs; and analytical developments are equally welcome. The session seeks to include work on GDEs across a wide range of physiographic and social contexts, including surface, unsaturated, and saturated zones; urban, rural, and coastal environments; and a wide range of socioeconomic and sociocultural contexts.