Valoración de la calidad de ribera en un arroyo pampeano y su relación con las comunidades de macrófitas y peces

Abstract

An Index of Riparian Quality was applied to a Pampean stream with moderate human impact (Las Flores stream, Luján river basin) to evaluate its degree of conservation. Aquatic macrophyte cover and diversity were also registered in 12 different reaches along the stream to analyze its relationship with the riparian index. In addition, the richness and diversity of the fish community were registered in two reaches with contrasting use of riparian zones and channel morphology. The results of the survey indicate that conservation of the riparian zones is difficult in the stream due to the increase of farming activities, the development of cropland near the margins, the invasion of an alien tree Gleditsia triacanthos (acacio negro) and the development of urban zones. Alteration of the riparian zone also modified the structure of the macrophyte communities and could be associated with a reduction in the richness and diversity of the fish community. We consider that the needs for conservation and recuperation of the riparian zones must be transmitted to the land owners. Activities should be coordinated to maintain the water quality and habitat diversity in order to enhance the basin health.