Abstract
In recent times, habitat models at the meso-scale have become widely accepted techniques to quantify the impact of hydro-morphological pressures on rivers. However, several limitations limit a broader applicability of such models: 1) field-based mesohabitat mapping is difficult in large nonwadable streams; 2) obtaining a reliable habitat-streamflow rating can be a highly time-consuming process, since it requires field mapping over many discharges; 3) the role of event-scale and medium term river morphodynamics, a crucial source of habitat variability, is mostly not accounted for. In this work we present the FHARMOR project, which aims at overcoming the above limitations, by exploring the application of complementary techniques to ground field measurements of mesohabitats, namely hydro-morpho-dynamic modeling and remote sensing techniques. This is tested on a suite of case studies featuring a gradient of hydro-morphological characteristics and channel size, located in the central-north Italian Alpine area, i.e. the Mareit/Mareta, the Ahr/Aurino and the Eisack/Isarco rivers. The expected outcomes from the FHARMOR project are: 1) a quantitative, comprehensive methodological framework able to effectively quantify fish habitat dynamics in Alpine river systems of different size and over long reaches; 2) future scenarios development of habitat availability in Alpine rivers in response to sediment management and river restoration.