Integrated Assessment of the Anthropic Pressure Level on Natural Water Bodies: The Case Study of the Noce River (Basilicata, Italy)

Fragmentation is a phenomenon that involves the transformation of large patches of natural habitats into smaller ones (fragments) that tend to be isolated from the originals. In this case, the degree of environmental fragmentation of the Noce River in the Basilicata region (Italy) will be analysed. Following the installation of hydroelectric plants, the river has undergone such alterations that it has been classified as a Heavily Modified Water Body (HMWB). Environmental fragmentation is caused not only by soil sealing, which causes the loss and subsequent fragmentation of natural patches, but can also be caused by major changes in natural patches. In the case of a territory crossed by a watercourse, these patches may be subject to changes in the natural course of the river or in the vegetation present close to it. The aim of this work is to calculate, through GIS applications, the level of fragmentation of the adjacent area surrounding the water body along which there are several hydroelectric plants. Through a change detection in 2006, 2013 and 2018, metric and biodiversity indicators will be calculated to define the level of anthropic pressure of the water body. The results reveal that the variation of the calculated indices, both for landscape metrics and diversity indices, concerned “natural” land use classes, whose variation caused fragmentation of natural patches by changing the shape of the water body.