Editorial: Conservation of groundwaters and their dependent ecosystems: Integrating molecular taxonomy, systematic reserve planning and cultural values

The fundamental importance of groundwater is indisputable. Comprising 97% of Earth's unfrozen fresh water, groundwater is essential to the global hydrological cycle and provides crucial ecosystem services. Aquifers, particularly shallow ones, are inhabited by diverse and unique invertebrates (stygofauna) and sometimes even fish that have adaptations to a lightless environment with limited productivity (Hose, Asmyhr, Cooper, & Humphreys, 2015). Many of these species are ‘short-range endemics’ (Harvey, 2002) and may only be known from one or two sampling bores (Karanovic, Eberhard, Perina, & Callan, 2013). Groundwater also sustains diverse surface ecosystems, ranging from swamps and baseflow-fed rivers through to large areas of groundwater-dependent terrestrial vegetation. These surface-expression groundwater-dependent ecosystems (GDEs) harbour rich troves of aquatic and terrestrial biodiversity and have significant ecological, economic, and cultural values (Kløve et al., 2011). In parts of the world where groundwater has been severely drawn down, contaminated, or both, there have been serious and often irreversible impacts on biodiversity, natural and agricultural productivity, and human well-being (Mammola et al., 2019).