Efecto de la actividad antrópica sobre la composición y diversidad de macroinvertebrados acuáticos en el río Cofre (sistema lótico andino colombiano)

Abstract

Objectives : In the present study the effect of human activity on aquatic macroinvertebrate communities in the Cofre River were analyzed, taking into account the spatial and temporal variation. Methodology : Four study sites were identified based on changes in pH and conductivity; organisms were collected according to the methodology proposed in this research, together with physic-chemical parameters as supplemental data; data analysis included diversity indices, tests of statistical significance (95% level) and multivariate analysis (CCA, PCA); sampling lasted six months. Result : At a spatial level significant differences (p 0.05), but if for the biological variables (except for the density); in terms of similarity between sampling stations, clustering was independent of the time, where higher spatial associations 70% was identified in the groups; in the compositions, Diptera order dominated. Conclusion : the spatial changes in the physicchemical and biological variables seem to be the result of the influence of the municipality of Totoro as anthropogenic pollution impact; in the temporal aspect, the dynamics of the river may have a certain influence on most diversity indices, but not on physic-chemical variables.