ARTÍCULO
Implications of macroinvertebrate taxonomic resolution for freshwater assessments using functional traits: the Paute river basin (Ecuador) case
Fecha
2021Autor
Sotomayor, Gonzalo
Goethals, Peter
Hampel , Henrietta
Vazquez Zambrano, Raul Fernando
Eurie Forio, Marie Anne
Institución
Resumen
Aim: This study aimed at investigating the taxonomic resolutions (TRs) of benthic
macroinvertebrates for freshwater assessments in the scope of the functional trait
approach (FTA).
Location: Macroinvertebrate samples were collected in 22 locations within the Paute
River Basin (PRB), Ecuador, over three years (2010, 2011 and 2012).
Methods: Biological traits were allocated as scores to the macroinvertebrate data (at
genus level) through fuzzy coding, using published data. The scores of each genus
were used to derive scores for the corresponding family. These two sets of scores
were standardized and compared, they were similar in 82% of the cases. Functional
diversity (FD) was described by the rRao index, which showed no significant differences between coarse (family level) and fine (genus level) TRs. Cluster analyses using
the K-means algorithm were performed to determine similarities between both rRao
data sets. The WQ cluster number (K) was varied between 2 and 5 to determine a
threshold K value (Kth), after which a WQ assessment differed as a function of the TR
being used.
Results: Kth was 3. Family-level identification in the framework of the FTA in the PRB
was suitable in detecting changes of macroinvertebrate assemblages (until Kth = 3).
Main conclusions: The proposed methodology could be implemented in other basins
where decision-makers could decide whether the level of functional trait data similarity is sufficient for WQ management purposes and whether the defined Kth is acceptable. The reliability of the key methodological steps was assessed using performance
statistics that have rarely been applied to ecological studies. Despite related research
performed in other regions, the present study is the first South American attempt to
investigate the effects of TR of benthic macroinvertebrates on freshwater bioassessments using functional traits