How to improve the conservation of species-rich grasslands with result-oriented payment schemes?

Specific mechanisms for result-oriented payment schemes using vascular plant taxa have been discussed as possible targeted approaches for promoting European species-rich grasslands. Most indicator lists are restricted to a limited number of frequently occurring indicator taxa. However, these lists often do not adequately reflect the most valuable grasslands in terms of conservation. Thus, we developed a procedure for selecting indicator species from an expanded checklist as well as a procedure for weighting indicator species based on their indicator power in terms of conservation criteria. The case study region was the federal state of Brandenburg (Germany). The database contained Brandenburg's vegetation mapping data and a simple indicator checklist from a previous agri-environmental program. For the conservation quality criteria, we used species number, number of extensive grassland species, number of threatened red list species and indices combining two of these criteria. The new expanded checklist resulted in 71 indicator taxa. We recommended a weighting factor that considers the indicator power of the index that combines extensively used species and red list species. Regression analyses were conducted to test the improvements resulting from each step of the approach. The determination coefficient of the regression between the number of indicator taxa and the quality index increased in the following order: simple checklist, expanded checklist and expanded weighted checklist (0.420, 0.654 and 0.782). The new, more differentiated list allows a 5-step payment approach. Generally, this procedure could be used to compile weighted indicator lists for other regions.