A method for assessing the ecological quality of riparian forests in subtropical Andean streams: QBRy index

Abstract

A modified QBR index adapted to examine the riparian quality of streams included within Yungas biome is presented. The index, named QBRy, comprehend modifications of the original index in three of the four sections in order to be useful for the studied region. The development of QBRy included trials in three subtropical sub-basins of Tucumán province (Argentina). Thirty-seven sampling sites were assessed. Forest riparian composition varied according to a geographical range of distribution, and this was related with the climatic differences existing within the same ecoregion. The quality of riparian vegetation was poor near population centers and in sites impacted by livestock, while good quality conditions were exhibited in adjacent areas to a protected region and in sites physiographical inaccessible. The introduction of exotic species represents a problem to the integrity of Yungas riparian vegetation. The protection of the few existing well-preserved riparian sites and the necessity of restoration of highly altered riparian ones becomes an essential priority in the long-term biodiversity sustainable.