Combining Habitat Suitability Models and Fluvial Functionality data for a multilayer assessment of riverine vulnerability.

"Abstract: Fluvial habitats are key ecosystems in maintaining landscape biodiversity for their role as corridors and filtering organisms. Since they are functionally linked to the surrounding territory, the health of riverine fauna populations depends on river\/landscape equilibrium. Thus, due to the anthropic pressures that in last decades have damaged many fluvial environments, the identifying of scientifically based management strategies devoted to restore the river environmental sustainability has become urgent. . Efficient restoration strategies may be valuable performed by analyzing the environmental needs of target species whose survival depends on the entire basin conservation status, e.g. the Eurasian otter Lutra lutra). In this work we use a Habitat Suitability model (Ecological Niche Factor Analysis) for the Otter to evaluate the river basin functionality and to identify sectors needing restoration measures. The input data have been land covers (from LANDSAT-TM images), a DEM and a derived SLOPE map; the model was performed in the Otter core area of its Italian range, within a riparian buffer of 300 m, producing a HS final map, categorized into three levels (unsuitable, suitable, optimal). The unsuitable areas represent unbalanced sites in term of ecological equilibrium for Otter habitats and can be used to locate restoration interventions having a general character as well as to refine the analysis for specific restoration activities. . In conclusion, the combined use of HS models\/satellite data represents a helpful support for management . policies efficiently suitable to improve the whole river functionality and to recreate balanced habitats for an endangered species as the Eurasian otter. . "