Ecosystem services of runoff marshes in urban lowland watersheds: proposals for conservation through the use of macroinvertebrates.

ARMENDÁRIZ L.; CORTESE B.; RODRÍGUEZ M.; RODRIGUES CAPÍTULO, A.

KNOWLEDGE AND MANAGEMENT OF AQUATIC ECOSYSTEMS

EDP SCIENCES S A

Lugar: Paris; Año: 2018 vol. 418 p. 1 - 12

1961-9502

Abstract: La Plata city (Argentina) is situated in a low alluvial zone,with streams having insufficient drainage into the Río-de-la-Plataestuary. In April 2013, a prodigious storm front produced unprecedentedflooding in the city and environs that resulted in the loss of many humanlives along with major material damage, in which crisis the basin of theDel Gato Stream was especially involved. Through an analysis of the waterquality and the conditions of the habitat on the basis of themacroinvertebrates present as bioindicators of environmental quality, ouraim was to contribute to a reevaluation of the role of the river´sadjacent runoff marshes as flood-alleviation elements and then proposealternatives for flooding management in the basin. We, accordingly, tookquantitative seasonal samples of vegetation, sediments, and benthicorganic matter and measured limnologic parameters in three sectors of thebasin having different land uses: rural, periurban, and urban-industrial.The macroinvertebrate asemblages, as analyzed through the application ofecologic indices, exhibited a marked decline in richness and in thepampean biotic index towards the low-lying basin. Principal-componentsanalysis associated Site 1 with the dissolved-oxygen concentration, Site2 with high nitrate values, and Site 3 with oxygen demands. Redundanceanalysis indicated a positive relationship between Baetidae andAeolosomatidae with the dissolved-oxygen concentration and betweenEnchytraeidae and Stratiomyidae with the conductivity. These marshes arefundamental in maintaining good environmental conditions and attenuatingthe effects of the flooding that is predicted to become increasinglycatastrophic in this region upon the changing climate