Environmental changes and macroinvertebrate responses in Patagonian streams (Argentina) to ashfall from the Chaitén Volcano (May 2008)

► Ashfall impact on water quality, environmental features and macroinvertebrates. ► Natural and unpredictable disturbances on freshwater ecosystem in Patagonia. ► Attributes of macroinvertebrate communities: composition, richness, abundance. ► Macroinvertebrate responses to environmental disturbances. ► Habitat deterioration, food quality diminution, interference with breathing mechanisms.