The evaluation of ecological status in a Large Portuguese River using Macroinvertebrates Assemblages

Abstract

great variety of taxonomic and functional feeding groups, which provides them advantages as indicators of the ecological status of aquatic ecosystems. The implementation of the Water Framework Directive in Europe led to an extensive use of biomonitoring programs in order to access the water quality of streams and rivers. Still, the established Portuguese sampling protocol for aquatic macroinvertebrates does not differentiate small wadeable streams and large nonwadeable rivers. The development of better standardized sampling methods and the identification of more suitable metrics and indexes are extremely important to obtain an accurate ecological status of rivers. Given the importance of the correct evaluation of ecological status in aquatic ecosystems management, our main objectives are: (1) to identify the vulnerability of the established sampling protocol and selected metrics to our sampling sites and (2) to present a review of the different studies which have been carried out during the last years in large rivers and that could be applied on further bioassessment programs in Portuguese large rivers, both feasible and cost effective.