Effects of Future Climate Change on a River Habitat in an Italian Alpine Catchment

AbstractThe impact of prospective climate change on the hydrological and ecological status of the mountain stretch of the Serio river (ca. 300  km2) in the Northern Italian Alps was investigated. A hydrological model was used to mimic theflow regime, and experimental suitability curves were used to assess weighted usable area (WUA) for brown trout (Salmo trutta) in different stages (adult, young, and spawning), and four macroinvertebrates families (Leuctridae, Heptageniidae, Limnephilidae, and Limoniidae). Discharge-WUA curves were obtained using instream flow incremental methodology/physical habitat simulation system (IFIM-PHABSIM), and a seasonal WUA assessment was carried out. The future (until 2100) hydrological cycle was projected using outputs from two general circulation models from Assessment Report 5 of the Intergovernmental Panel on Climate Change (IPCC). The results display a potential for a large flow decrease yearly, until −60% at 2050 and −56% at 2090. Spring melt peaks will be largely dampe...