Appendix A

Appendix A: Comparison of similar tools in Europe

The methods and figures are substantiated by thorough literature research and empirical research in Flanders. We compared a number of existing similar tools and looked at their approach to certain ecosystem services. In this appendix you will find a brief overview of our findings.

There are two major groups of tools:

The spatially explicit tools such as ARIES (Assessment and Research Infrastructure for Ecosystem Services) and InVEST (Integrated Valuation of Environmental Services and Tradeoffs). Both tools use map data (depending on the ecosystem service) to spatially explicitly estimate the production of ecosystem services. Using these tools, the effects on ecosystem service production of different management and land use scenarios can be calculated. The output of such tools consists of a series of ecosystem service specific map layers. The user must therefore collect all the necessary map data himself and convert the scenarios to be analyzed into potential land use maps. Based on these maps, different models then calculate the (monetary) values of some specific services. The user must make his own estimates of prices and quantities, e.g. the amount of carbon stored. InVEST does have a book that describes process-based comparisons based on current knowledge in ecosystem services research. This does provide a starting point for calculating the quantities, but the tool does not calculate them itself. If enough data is available, the tool is relatively easy to apply because of a freely available ARCGIS toolbox. A certain knowledge of GIS is necessary. ARIES, on the other hand, focuses more on the uncertainties associated with the production of ecosystem services and uses Bayesian belief networks for this. Calculating scenarios using ARIES is less easy compared to InVEST and requires broader knowledge about the background of the ARIES tool.

The calculation tools that, like the Nature Value Explorer, offer a simple calculation method for the quantification and valuation of ecosystem services, such as the Alterra WECAN tool (not available to the general public) and the Green infrastructure toolkit (<http://www.greeninfrastructuresw.co.uk/ html/index.php?page=projects&GreenInfrastructureValuationToolkit=true>) cover a wide range of ecosystem services. The methods used are partly comparable to those of the Nature Value Explorer. The Nature Value Explorer distinguishes itself from this by making spatially explicit calculations and providing more functions where the quantification and/or valuation is not only based on key figures, but on (simplified) calculations in the tool that take into account specific characteristics of areas and processes in the ecosystem. The Nature Value Explorer makes estimates for more services and uses more recent figures. Just like the Nature Value Explorer, these are also "living tools" that can be further developed as more and/or better knowledge and data become available.

A tool that lies somewhere between both groups of tools is the ECOPLAN-SE tool. This tool uses simple calculation methods and is spatially explicit. The tool is a QGIS plugin. A major difference with the Nature Value Explorer is that the calculation is done at a lower resolution (5x5m grid) while the Nature Value Explorer calculates on a polygon basis. The disadvantage is that a certain knowledge of QGIS is necessary to use the tool. This knowledge is not necessary for the Nature Value Explorer. The methods of ECOPLAN and Nature Value Explorer were aligned as much as possible.