European maps of potential species richness of wetland species created with the BioScore model - Deliverable 4.2 of WET HORIZONS project

This repository contains European maps of potential species richness of wetland species under current environmental conditions for vascular plants (VascMap.tif), mosses (MossMap.tif), lichens (LicMap.tif) and birds (BirdMap.tif), as created with the BioScore model. 

Methodology used to generate the maps

As part of WET HORIZONS, PBL Netherlands Environmental Assessment Agency has extended the BioScore modelling framework, which is a species-level biodiversity model of vascular plants in Europe. We have improved its ability to evaluate and predict the impacts of various environmental pressures on wetland biodiversity. BioScore consists of species distribution models (SDM) that estimates species distributions based on quantitative relationships between species observations and environmental conditions. This model employs species occurrence data and environmental variables to create an overall output that generates species-specific maps based on probability of occurrence. In WET HORIZONS, we have improved BioScore by adding species characteristic of wetlands, including 210 vascular plants, 55 mosses, 14 lichens, and 35
birds guided by current data availability. We have incorporated environmental variables relevant for wetland conditions, including groundwater table depth, moisture accumulation, inundation probability, and the proportion of anthropogenic (human-dominated) land cover upstream of wetland sites. A full description of the methodology used to generate the maps is described in Deliverable 4.2 of the WET HORIZONS project, entitled "Improved BioScore model and corresponding European wide spatially explicit model output for the current  situation (baseline)". 

We established potential species richness maps by stacking per taxonomic group the species-specific probability of occurrence maps as generated by the improved BioScore model, and then dividing the summed probability of occurrence by total number of species per taxonomic group.

Interpretation of the maps

The potential species richness maps highlight where environmental conditions might support wetland species, offering a broad view of potential biodiversity across the continent. We acknowledge that SDMs in general and the BioScore modelling framework in particular are simplifications and that predictions are associated with uncertainties. For example, the models do not account for all environmental variables that determine species distributions or all ecological interactions. Though not reflective of actual local species richness, these maps can guide the prioritization of areas for conservation and restoration. 

This publication is supported by the WET HORIZONS project.