Assessment and analysis of the morphological condition of the High Cordevole River (Bl, Italy) whith the MQI index

In this paper we present the application of the new Morphological Quality Index (MQI), which is a part of hydromorphological assessment system, analysis and monitoring of Italian water courses (IDRAIM), to evaluate the morphological quality of the Cordevole River upstream of Lake Alleghe. IDRAIM has been promoted by the Institute for Environmental Protection and Research following the Water Framework Directive. The analyzed water network (only collectors greater than third-order were considered), has been divided, through the use of the GIS software, into 41 river reaches with homogeneous morphological characteristics, according to the first phase of the method. The application of 28 indicators was carried out for 14 reaches of the Alto Cordevole, 9 of the Fiorentina, and 8 of the Pettorina streams. The results showed that 50% of the analyzed reaches have a moderate morphological status, 25% have a good quality, 20% a very good quality, while only one case has the characteristics to be considered a Heavily Modified Water Body (HMWB). The main causes that lead to a strong alteration of the terms of reference are linked to i) poor connectivity between hillslopes and river corridor; ii) absence of vegetation in the river corridor; iii) presence of artificial elements, particularly the bedload interception structures in the catchment, bank protection along the reach, and the removal of sediment, large wood and vegetation.