US EPA

3354063 

Journal Article 

Assessing the performance of macroinvertebrate metrics in the Challhuaco-Nireco System (Northern Patagonia, Argentina) 

Mauad, M; Miserendino, ML; Risso, MA; Massaferro, J 

2015 

Yes 

Iheringia. Serie Zoologia
ISSN: 0073-4721 

105 

3 

348-358 

English 

10.1590/1678-476620151053348358 

WOS:000366197400011 

Seven sites were examined in the Challhuaco-Nireco system, located in the reserve of the Nahuel Huapi National Park, however part of the catchment is urbanized, being San Carlos de Bariloche (150,000 inhabitants) placed in the lower part of the basin. Physico-chemical variables were measured and benthic macroinvertebrates were collected during three consecutive years at seven sites from the headwater to the river outlet. Sites near the source of the river were characterised by Plecoptera, Ephemeroptera, Trichoptera and Diptera, whereas sites close to the river mouth were dominated by Diptera, Oligochaeta and Mollusca. Regarding functional feeding groups, collector-gatherers were dominant at all sites and this pattern was consistent among years. Ordination Analysis (RDA) revealed that species assemblages distribution responded to the climatic and topographic gradient (temperature and elevation), but also were associated with variables related to human impact (conductivity, nitrate and phosphate contents). Species assemblages at headwaters were mostly represented by sensitive insects, whereas tolerant taxa such as Tubificidae, Lumbriculidae, Chironomidae and crustacean Aegla sp. were dominant at urbanised sites. Regarding macroinvertebrate metrics employed, total richness, EPT taxa, Shannon diversity index and Biotic Monitoring Patagonian Stream index resulted fairly consistent and evidenced different levels of disturbances at the stream, meaning that this measures are suitable for evaluation of the status of Patagonian mountain streams. 

Patagonian; macroinvertebrates; biotic indexes; water quality; EXOTIC RAINBOW-TROUT; ANDEAN STREAM; WATER-QUALITY; BENTHIC; MACROINVERTEBRATES; HEADWATER STREAMS; COMMUNITIES; PLECOPTERA; ASSEMBLAGES