Reserve selection for conserving groundwater biodiversity

Abstract

SUMMARY1. A possible conservation strategy to minimise the risk of groundwater biodiversity loss due to human activities consists in designing a network of reserve areas at the continental scale that collectively include most groundwater species. To this end, we compared the efficiency of three area selection methods (species richness hotspots, endemism hotspots and complementarity) and examined the influence of spatial constraints (reduced extent and increased aggregation of reserve areas) on the representation of 1059 groundwater species in six European regions. 2. Presence data from a data base elaborated as part of a European initiative on groundwater biodiversity, the PASCALIS project, were referenced onto 4675 grid cells (0.2 by 0.2°). Complementary performed much better than traditional selection methods for maximising species representation in a reserve network arbitrarily limited to 10% of all the cells containing groundwater fauna. It captured 155 more species than areas selected on richness and 77 more species than areas selected on endemism hotspots. 3. Representing species in a specified proportion of their area of occupancy (i.e. 100%, 50% and 10% of the area of occupancy of species occurring in 1, £10, and >10 cells, respectively) required inclusion of 46% of the cells containing groundwater fauna. The reserve network needed to achieve this level of coverage may be too large and fragmented to be implemented and managed in practice. 4. Reduction of the reserve areas to 10% of the landscape containing groundwater fauna and their aggregation into a smaller number of cell clusters resulted in a more realistic reserve network that represented 73.8% (782 species) and 59.1% (274 endemics) of the total number of species and endemics, respectively. 5. We propose several research priorities to improve the design of effective groundwater reserve networks in Europe: (i) devising sampling strategies that reduce uncertainties in the placement of reserves and increase the number of alternative reserve networks and (ii) shifting from a grid-cell selection approach to an aquiferselection approach that incorporates species representation targets, minimum space requirement and also socio-economic costs related to the vulnerability of aquifers and degree of human activity in the catchment.

The invertebrate ecology of the Chalk aquifer in England (UK)

“…However, in general, groundwater ecosystems are not considered in water management programs. Nevertheless the Chalk aquifer has been identified as a habitat for invertebrate groundwater fauna in England (Proudlove et al 2003;Robertson et al 2009;Sorensen et al 2013;Johns et al 2015), and fauna are recorded from Chalk areas in continental Europe Martin et al 2009;Michel et al 2009); however, it is unclear in some of these studies which samples came from the Chalk, and questions remain about where in the aquifer invertebrates occur, and how commonly they occur. The prevalence of species in the Chalk and the importance of the Chalk as an ecological habitat have not been properly assessed.…”

VIEWPOINT. Is the Australian subterranean fauna uniquely diverse?

“…More than 650 stygobitic species have been recorded from the longest and most intensively researched region, the Balkan Peninsula, where the first stygal animal was described in 1768, and from where 975 species of troglofauna have been recorded . Slovenia, a key cave region in Europe, has 114 known stygobitic species (Culver and White 2004), while six other European countries (Belgium, France, Italy, Portugal, Slovenia, Spain Michel et al 2009)) have recorded 1059 stygobitic taxa with no more than 80 species from any one karst region. Most of these taxa are considered remnants of the Pleistocene, during which time cave populations were colonised during interglacial cycles, and isolated during glacial periods (Peck 1984;Peck and Christiansen 1990;Culver et al 2006).…”

Pilbara stygofauna: deep groundwater of an arid landscape contains globally significant radiation of biodiversity

“…A recent European study by Michel et al (2009) to compare methods of selecting reserves for the conservation of stygofauna showed that use of a complementarity algorithm led to more effi cient protection of species than selecting reserved areas on the basis of high richness or endemism. However, the area of occupancy criterion chosen by Michel et al (2009) required that 46% of cells known to contain stygofauna in Europe were conserved.…”

“…However, the area of occupancy criterion chosen by Michel et al (2009) required that 46% of cells known to contain stygofauna in Europe were conserved. Given that stygofauna occur over most of the Pilbara, such an extensive network of groundwater reserves for stygofauna is unlikely to be achievable, especially considering the spatial extent of groundwater drawdown associated with some large mines (Johnson and Wright 2001).…”