Web tool for prioritizing conservation in Europe

Facilitating site prioritization assessments for European freshwater conservation intervention projects

The Nature Conservancy (TNC) Europe Freshwater Team is conducting a geographic prioritization assessment to identify locations for implementing freshwater related conservation interventions. To facilitate this analysis, Confluvio has created a custom decision support system web app tailored to the needs of the freshwater team. The implementation of the site prioritization tool will help TNC identify priority areas in Europe, beyond their current geographies of engagement, for achieving their strategic goals and maximizing benefits to nature and people.

At the core of the decision support system is the HydroSHEDS framework and a collection of 50 data layers. The data collection was curated to include the most relevant and up to date data layers available to enable the assessment of freshwater biodiversity, freshwater ecosystem diversity, enabling conditions, the current state of natural systems, climate change impacts, human development, and additional layers incorporating specific criteria of the TNC Europe Freshwater Team. Data were processed to integrate disparate data sources into the HydroSHEDS framework, providing a consistent scale of analysis using the HydroBASINS level 10 catchment delineations as the spatial unit of analysis.

Components, concepts, and technologies used in building TNC's decision support tool for identifying and assessing freshwater conservation priorities.

There are four different types of functionality provided by the tool.

The primary function of the decision support system is conducting a weighted overlay analysis to determine high priority catchments for conservation interventions based on custom user specified prioritization criteria. The prioritization analysis is streamlined into four interactive tabs: explore, filter, prioritize, and analyze.

The explore functions enable users the ability to familiarize themselves with the data layers provided in the tool. This is the first step of the prioritization analysis with functions contained in this tab for displaying the data values in the map display and providing access to additional metadata information.

The upper and lower limits of the raw data values of each layer can be set explicitly, resulting in the filtering of the layer to a specific set of catchments that meet the value range.

The filter tab was designed to allow users to specify criteria that must be met for a catchment to be considered in the prioritization analysis. The functions contained in the filter tab allow for interactive queries to be applied to the data layers. An interactive slider is available that can be used to easily filter the data to a specific range. After a filter has been applied or changed, the map display updates automatically showing the results of the data queries. Queries for multiple layers can be applied simultaneously allowing for a complex set of criteria to be easily applied following a few clicks.  

Each layer can be prioritized using a simple weighting system using 0-3 stars. Using the assigned weights, the layers in each thematic group are combined using weighted overlay techniques. In turn, all thematic groups are also weighted and combined into a combined score for the strategic pillar.

The prioritize tab provides the main functions of the prioritize analysis where users decide which layers are included in the analysis and how strongly the layers are weighted. Users are also provided the option to reverse the direction of optimization allowing users the option to prioritize a layer based on either high or low data values. For the prioritization analysis, the data are first normalized, the user specified weights are applied, and a weighted average is calculated to produce a prioritization map for Europe. The map provides an aggregate prioritization score where high values indicate locations where desirable conditions coincide. The results of the prioritization analysis can then be analyzed using the functions contained in the analyze tab.

The analyze tab provides functionality to further investigate the results of the prioritization analysis at three different spatial scales: catchments, river basins, and countries. Within the map display, users can select spatial units at these three spatial scales to calculate statistics for the prioritization results within the selected area. The statistics are divided into four categories: information, prioritization score, no data, and goals. These categories provide descriptive statistics pertaining to area and landcover proportions, details to tease apart the contributions of indicator groups in the prioritization scores, the reliability of the prioritization scores with regards to the inclusion of no data values in the calculations, and metrics related to conservation goals outlined by TNC, respectively. The goals section includes statistics important to TNC's strategic planning goals, specifically maximizing benefits to nature and people. We calculated statistics providing the protection of rivers, protected surface area, the proportion of natural surface area, and population metrics.

The strength of the decision support system we created is the integration of many data sources and the simplified workflow for conducting prioritization analyses. The decision support system integrates many data sources allowing for the creation of a wide variety of prioritization scenarios to suite the needs of TNC. These scenarios can easily be generated and analyzed through the custom web app interface without requiring extensive technical expertise, enabling science-based decision making for freshwater conservation throughout Europe.

Example prioritization statistics calculated at the country level.

The app is featured in TNC's  Geospatial Annual Report 2022. See the news release and download a copy of the report here: