Influence of riparian quality on macroinvertebrate assemblages in subtropical mountain streams

Abstract

The type and extent of riparian vegetation is known to have a significant influence on macroinvertebrate communities. The objective of this work was to assess the influence of the quality of a subtropical riparian forest on the structure and composition of macroinvertebrate assemblages. Lower diversity and richness of invertebrates has been found in degraded reaches in comparison with native forested sites. Richness, diversity and density of collector-gatherers were sensitive to the quality of riparian vegetation. Native riparian species at sites of good riparian quality contribute to greater habitat complexity and higher quantities of palatable food, determining the differences in the structure of macroinvertebrate assemblages between sites. This work suggests the use of the IBY-4 index in future management studies of Yungas streams because of its sensitivity to changes in riparian conditions.

Keywords:

• biotic index
• ecological condition
• macroinvertebrate diversity
• northwestern Argentina
• subtropical forest

Acknowledgements

The author thanks C. Reynaga, H.R. Fernández, C. Nieto, C. Molineri, V. Manzo, F. Romero, E. Tejerina, P. Rueda Martín and M. del V. Correa for their assistance in sample identification, and is grateful for the comments of the reviewers, which improved the quality of the manuscript.