Evidence of Taxonomic and Functional Recovery of Macroinvertebrate Communities Following River Restoration

Abstract

River ecosystems have been heavily degraded globally due to channel hydromorphological modifications or alterations to catchment-wide processes. Restoration actions aimed at addressing these changes and restoring ecological integrity are increasing, but evidence of the effectiveness of these actions is variable. Using a rare 7-year before-after-control-impact (BACI) study of restoration of a lowland groundwater-fed river in England, UK, we explore changes in the macroinvertebrate community following the removal of impoundments and channel narrowing to aid restoration of physical processes. Restoration activity prompted significant taxonomic and functional responses of benthic invertebrate communities in the 4 years post-restoration. Specifically, significant gains in taxonomic and functional richness were evident following restoration, although corresponding evenness and diversity measures did not mirror these trends. Restoration activities prompted a shift to more rheophilic taxa and associated traits matching the physical changes to the channel and habitat composition. Temporal changes were clearer for taxonomic compositions compared to the functional properties of macroinvertebrate communities, indicating a functional redundancy effect of new colonists inhabiting restored reaches following restoration. The results highlight the value of long-term BACI studies in river restoration assessments, as well as project appraisals incorporating both taxonomic and functional observations. We highlight the urgent need of such studies to provide evidence to inform effective river restoration strategies to address future changes such as adaption to climate change and the biodiversity crisis.

Diversidad Funcional Y Taxonómica De Insectos Acuáticos (Ept) en Un Río Urbano Del Piedemonte Llanero Colombiano

“…La divergencia funcional más alta se registró en las estaciones de la zona alta y baja con predominancia de uso del suelo natural, ganadería y agricultura, lo que favorece la variedad de rasgos funcionales y la complementariedad de nicho (Mason et al, 2013). En estas zonas las estaciones presentaron variaciones similares entre rasgos funcionales que no se evidenciaban en las demás zonas, por lo que hay mayor ocupación de nicho y redundancia funcional en las estaciones de cabecera y en la zona baja del río (England et al, 2021). Biol Colomb, 28(2) 251 -262 Mayo -Agosto 2023 La mayor riqueza de géneros efectivos ( 0 D) se presentó en la zona alta con predominancia de uso del suelo natural y en la zona baja donde predominó el uso del suelo ganadería y agricultura; el tramo alto del río presentó relieve inclinado, cauce con piedras y gravas, con fondo arcillo-arenoso, buena calidad fisicoquímica del agua que son características de una corriente conservada o de buena calidad (Torres-Mora et al, 2015;Zamora, 2015).…”