A new protocol for assessing the conservation priority of groundwater-dependent ecosystems

1. Species of conservation concern are usually considered important elements in siteprioritization for biodiversity conservation. To overcome the lack of informationon species conservation status, multidimensional measures of species rarity canbe used as proxies of species vulnerability.2. Under this assumption, a two-step protocol for site prioritization of aquaticgroundwater-dependent ecosystems is proposed using invertebrate vulnerabilityestimated from species' traits. In the first step, each species occurring in the sitesof interest are scored according to their vulnerability. In the second step, sites areprioritized using species' scores.3. Species vulnerability scores are based on five dimensions, for which various traitsare scored: (i) geography, (ii) ecology, (iii) biology, (iv) population, and (v) evolutionaryhistory. For each species, the scores of the various traits belonging to the samedimension are multiplied to obtain a synthetic score. These scores are then rankedinto four classes and, for each dimension, each species receives a new score thatreflects its rank. The sum of these scores represents the species' overall score.4. Site conservation priorities are assessed by combining species scores into threeindices: Sum of Species Scores, Biodiversity Conservation Concern (which relates thesum of species scores with the local species richness) and Groundwater BiodiversityConcern (which is the average of the former two). The protocol is illustrated usingcase studies in Italy and it is fully implemented in the software AQUALIFE which isfreely available at: http://app.aqualifeproject.eu by registered users.5. Sensitivity analyses showed that the protocol is robust against the lack ofinformation on species biology or sampling limitations. However, trait scoringrests with the user, who must be familiar with the study group.6. This approach can be applied at any spatial scale and to different types of aquaticgroundwater-dependent ecosystems.