Global overview on groundwater fauna

Abstract

Groundwater is an important global resource, providing water for irrigation, industry, geothermal uses, and potable water all over the world. Moreover, groundwater contains the world’s largest terrestrial freshwater biome. Groundwater faunal communities undertake important ecosystem services including the provision of clean water. Despite this, investigations on the spatial and temporal variations and the influence of environmental parameters on these organisms, are still rare. The aim of this study is to provide a global overview on groundwater fauna (stygofauna) research, including the historical evolution of research topics and development of sampling methods. To achieve this, an extensive review of accessible groundwater fauna data was conducted. Over time, there has been an exponential increase in the number of studies together with changing paradigms in the research focus, particularly as sampling methods have developed and molecular analyses become common. Studies on groundwater fauna are spatially uneven and are dominated by studies in Europe and Australia, with few studies in Africa, Asia and the Americas. This has resulted in a potential geographic and climatically biased global view of stygofauna and groundwater ecology. In the future, a more evenly distributed sampling effort in underrepresented areas is necessary to enable global studies, thus allowing a more comprehensive perspective on stygofauna biodiversity, roles, and functional significances. This is increasingly important with the accumulating knowledge of the sensitivities of these ecosystems to anthropogenic activities, including climate change, and is fundamental to effective management of these ecosystems.

Rapid detection of subterranean fauna from passive sampling of groundwater eDNA

“…Most subterranean fauna species have extremely limited distributions and are difficult to discriminate morphologically due to strong selection pressures and convergent characteristics. Despite considerable research in the last decade, much of the fauna remains poorly understood (Guzik et al., 2010; Koch et al., 2022; Saccò, Blyth, et al., 2022). Most estimates of subterranean fauna biodiversity are likely to be an underestimate, with this knowledge gap becoming a significant issue for both biodiversity conservation and environmental impact assessments (Danielopol et al., 2007; Mammola et al., 2022; Niemiller et al., 2018).…”