Epixylic algae from a polluted lowland river of Buenos Aires province (Argentina).

RODRÍGUEZ, P; H. PIZARRO; N. MAIDANA; M. DOS SANTOS AFONSO; S.M. BONAVENTURA

CRYPTOGAMIE. ALGOLOGIE

Elsevier Science

Lugar: Paris; Año: 2006 vol. 27 p. 63 - 83

0181-1568

Summary We analyzed the influence of spatial and temporal variations in the physical and chemical properties of the water on the specific composition of the periphytic algae attached to wooden posts (epixylon) in a section of the low river Luján (Buenos Aires, Argentina) and in a tributary, both of which were subject to different degrees of exposure to wastewater. Algae and water samples were taken almost monthly from July 2000 to July 2001. During this period river Luján and its tributary had very poor water quality and their physical and chemical characteristics were typical of polluted urban rivers. In terms of richness, all sites showed dominance of Bacillariophyceae, followed by Cyanobacteria, Chlorophyta and Euglenophyta. Algal taxa were typical of polluted rivers and some of them were adapted to desiccation due to strong fluctuations in the hydrological level of the river. The RDA analysis indicated that species composition and richness exhibited a stronger response to seasonal and spatial variability of the limnological characteristics of the system rather than to inputs of domestic and/or industrial pollutants. This was probably because the whole epixylic communities from the low river Luján were composed by algae adapted to polluted watercourses with frequent peaks of pollutants.