Implications of macroinvertebrate taxonomic resolution for freshwater assessments using functional traits: The Paute River Basin (Ecuador) case

Abstract

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 (K th ), after which a WQ assessment differed as a function of the TR being used.Results: K th was 3. Family-level identification in the framework of the FTA in the PRB was suitable in detecting changes of macroinvertebrate assemblages (until K th = 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 K th 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.

Spatial patterns of macrobenthos taxonomic and functional diversity throughout the ecotones from river to lake: A case study in Northern China

“…Functional diversity measures are increasingly being incorporated into making better conservation and restoration decisions for freshwater ecosystems (Cadotte et al, 2011;Schmera et al, 2017;Coccia et al, 2021). Using several functional trait indices is likely to provide more insight into functional attributes of the ecosystem than relying only on species-based indices (Gagic et al, 2015;Sotomayor et al, 2021). In the present study, we investigated the spatial patterns of macrobenthos taxonomic and functional diversity along the gradient from the Fu River to Baiyangdian Lake.…”

Occurrence Prediction of Riffle Beetles (Coleoptera: Elmidae) in a Tropical Andean Basin of Ecuador Using Species Distribution Models

“…Model performance is likely to be compromised using genera instead of species taxonomic level since genera can contain several different congeners, which could have different ecological requirements. However, all study genera prefer clean water conditions [ 34 , 35 , 86 ]; as such, it is assumed that congeners within each genus also have similar preferences. Hence, it is assumed that, under the current conditions, the model performance is only being compromised in a marginal level.…”

“…The high probability values of Austrolimnius , Heterelmis , and mainly Austrelmis are rarely predicted in most parts of the Burgay and Magdalena sub-basins ( Figure 4 ), which have been described as polluted systems where the domestic and industrial wastewater discharge, extensive agriculture, cattle ranching, and the loss of native vegetation cover are the anthropogenic threats that cause severe surface water quality pollution and the subsequent loss of benthic macroinvertebrates taxa [ 21 , 34 , 35 , 132 , 133 ]. For the study basin, Sotomayor et al [ 21 , 86 ] found that Elmidae is a keystone family in establishing adequate stream water quality assessments. Thus, despite the dissimilarity of genera in the Elmidae family regarding their ecological requirements, the overall trend of elmid members is that their occurrence probability in the study basin is higher in areas with good levels of conservation, e.g., protected areas ( Figure 6 ).…”

“…For each elmid genus, its 12 AUC values were aggregated into a single value using central tendency measures. Before this aggregating process, the normality of each set of 12 AUC values was checked [ 35 , 86 ] using the Shapiro–Wilk (S–W) test [ 87 ] considering a 95% confidence level. For a particular elmid genus, if the S–W test suggested normality, the mean AUC value was used for aggregating; otherwise, the median was assigned as the aggregated AUC value [ 88 , 89 ].…”

Biological traits, geographic distributions, and species conservation in aquatic ecosystems

“…Due to limitations in time, funding, and natural history expertise, trait‐based approaches to community ecology may be more tractable in many applications than taxonomy‐focused approaches. For example, Sotomayor et al (2022) collected macroinvertebrate samples from 22 locations within the Paute River Basin in Ecuador to investigate taxonomic resolutions using functional trait (rRao index) and cluster analyses using the K‐means algorithm in the freshwater benthic macroinvertebrates in the South American. The results indicated that the family‐level identification using the functional trait approach was suitable in assessing the macroinvertebrate community of these rivers.…”