Habitat Quality Analysis of Natura 2000 Riparian Forests

Riparian forests are sensitive habitats with a rich biodiversity and an important function as corridors for movement of wildlife. In Europe, many of these precious habitats are protected sites within the Natura 2000 network, where monitoring results have to be reported every six years. Satellite imagery provides key benefits for monitoring nature protection areas where political borders, rough terrain and large and/or complex monitoring areas handicap a harmonized assessment (VANDEN BORRE et al. 2011). NAGENDRA et al. (in press) name four critical aspects of assessment: changes in habitat extent and landscape structure, habitat degradation, alteration in biodiversity and tracking of pressures and threats within and outside protected areas. As silviculture inside Natura 2000 sites can influence these aspects, a targeted monitoring is needed. For this purpose, an Earth observation-based workflow has been developed within the MS.MONINA project (http://www.ms-monina.eu) to monitor riparian forests in the Natura 2000 site Salzachauen. It includes (1) a habitat delineation based on visual interpretation and semi-automated object-based image analysis and (2) an assessment of habitat quality using structural indicators (cf. STRASSER et al. in review). In this paper, we focus on the second part of this workflow. We used landscape metrics to assess the overall habitat quality of the entire area and differentiated between three subregions with a different degree of silvicultural intensity to reveal potential influence of forest management on the habitat quality.