Florix, an index to assess plant species in floodplains for nature conservation – Developed and tested along the river Danube

Natural floodplains are ecosystems with a diverse mosaic of habitats and site conditions, but also highly threatened due to anthropogenic pressures. Plant species occur in all habitat types can indicate their value for nature conservation. To improve sustainable management rivers floodplains, several indices such as the River Ecosystem Service Index (RESI) have been developed. However, there so far no assessment schemes entire range floodplain plants. The common approaches like biological integrity, achievement rates or (Red list), applying other groups ecosystems, not appropriate floodplains. Legal obligations need restore clearly call an index assessing ecological reference area which be combined 5-scale accordance established assessments RESI Water Framework Directive. Five typical characteristics describing vascular plants’ adaptation were identified. These derived from published data sets available Germany. We checked these indicators multicollinearity selected three them: number, hydrodynamic indicators, conservation indicators. Species number correlate geographic occurrence. For we determined thresholds group indicator rate five classes (very low very high conservation). valid river Danube scrutinized this study. Florix approach was sensitive testing active against former protected unprotected areas: region ‘Danube floodplain’, values higher areas. Only type ‘water bodies’ showed better scores floodplain, ‘softwood forests’ status being part had effect. results validated two case studies differing land use intensity. dominant agricultural significantly lower than that portion forests grasslands. used floristic at single level entity study comparison region. It allows identify main pressures complement habitat-type based evaluation. achieve comparability, should strive generalized monitoring Europe it is aquatic ecosystem monitoring.