An index to evaluate the fluvial habitat degradation in lowland urban streams

COCHERO, J.; CORTELEZZI, A.; TARDA, A.S.; GÓMEZ, N.

ECOLOGICAL INDICATORS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 71 p. 134 - 144

1470-160X

The objective of the present article is to propose an index that allows the assessment of the detriment of the fluvial habitat in lowland urbanized streams, by combining metrics related to the watercourse, the river banks, the riparian zone and the fluvial geomorphology. The metrics contained in the index (USHI, Urban Stream Habitat Index) consider: the cover and quality of the aquatic vegetation; the characteristics of the river banks; the presence of exotic trees, of litter or permanent structures such as buildings in the riparian zone; and any significant geomorphological alterations, such as dredging or channelization. The correlation of the index with parameters related to water quality, the imperviousness of the watershed and to biotic descriptors, particularly the macroinvertebrate and diatom assemblages, highlights its sensitivity to express the overall habitat quality of the sites. Unlike other indices that evaluate the quality of the physical habitat through the use of the diatoms or macroinvertebrate communities, the USHI uses indicators that do not require the identification of taxa, making it more accessible to non-specialists. Therefore it provides a tool to evaluate the fluvial habitat of lowland streams of easy application, particularly by professionals that take part in the management and decision making process regarding water courses.