Advancing tools for the assessment of ecological flow in rivers

Alpine streams are widely affected by hydrological and morphological alteration caused by impoundments and water abstractions for hydropower generation. Flow management in Italian regulated rivers is based on minimum flow quantification according to the Ecological flow (EF) approach as defined by decree n. 30/STA, 13.02.2017. To include the EF approach to meet the Water Framework Directive (WFD, 2000/60/EC) requirements, in Italy the STAR_ICMi, based on benthos macroinvertebrate, is one of the biological index currently adopte (a multimetrix index). Several critics have been raised about the reliability of this method for application in alpine regions, based on its scarce effectiveness in measuring alterations of the flow regime. The purpose of the PhD project is to understand which alternative approach can effectively assess flow alterations of using the macroinvertebrate community. To propose a new index, we will: i) investigate the current existing methods that keep in account the relationship between the biota and the flow regime; ii) evaluate the most common models to identify factors that influence the response of the benthic communities to specific hydrological gradients. The final goal is to develop index/ices based on biological and hydrological data, both from field and monitoring programs, which are specifically sensitive to hydrological alterations, to determine and monitor ecological flows.