title: [The benthonic community as bioindicator of altered and recovering zones in Toledo creek (Uruguay)].
abstract: Macrozoobenthos composition and abundance of an organic polluted stream (A. Toledo, Uruguay) are compared among sites of control (C), degradation (D) and recuperation (R), which were seasonally sampled. Water ionic composition, conductivity, pH, temperature and COD were not different among sites, while oxygen, and BOD did show significant differences. Benthos was more abundant in R mainly due to Heleobia spp. Oligochaetes were dominant in C and D, with Branchiura sowerbyi only in C and Limnodrilus hoffmeisteri in D. Hirudinea, mainly Gloiobdella michaelseni, occurred almost only in R. the richness of taxa was higher in R, but its high abundance of Heleobia spp. and Sphaeridae leads to the lowest diversity, which was higher in C than D, and in warm than in cold seasons for these two sites. The logarithmic distribution model shows communities of low evenness in all sites.
authors.affiliation: Sección Limnología, Facultad de Ciencias, Montevideo, Uruguay.
authors.forename: R
authors.initials: R
authors.lastname: Arocena
mesh_terms: D000818:Animals; D017753:Ecosystem; D014583:Uruguay
vernacular_title: La comunidad bentónica como indicadora de zonas de degradación y recuperación en el arroyo Toledo (Uruguay).