Abstract
In this study, we assess the potential of ants as bioindicators of riparian ecological health in two river types (upland and lowland type) located in the Catalonian region. We proposed to understand to what extent do metrics based on ant responses provide useful information that cannot be presented by traditional biophysical assessments while attempting an approach to creating an ant-based multimetric index (ant-based MMI) of the riparian ecological health. A total of 22 ant species were identified, and 42 metrics related to ant foraging activity, species richness, and functional traits were evaluated as potential core metrics of the index. Riparian features and proximal land use land cover (LULC) were used to distinguish disturbed from less disturbed sites. We found that ant communities strongly responded to human disturbance. When compared with an exclusively physical-based index for the assessment of the riparian health, the ant-based MMI was more sensitive to human disturbance, by also reacting to the effects of the surrounding LULC pressure. This study provides a preliminary approach for an ant-based assessment tool to evaluate the health of riparian corridors although additional research is required to include other river types and a wider stressor gradient before a wider application.
Highlights
Riparian zones are complex multidimensional systems, responsible for many ecological functions considered crucial to the preservation of river well-being [1,2]
We showed that several ant metrics can be useful indicators of human disturbance in the Catalonian riparian corridors, as shown by the significant differences between disturbance groups
The results indicate that human disturbance has led to an increased urban land use land cover (LULC), reduced vegetation cover and a smaller width of riparian cover in riparian corridors of Catalonia, leading to significant differences in ant species composition
Summary
Riparian zones are complex multidimensional systems, responsible for many ecological functions considered crucial to the preservation of river well-being [1,2]. Ants were recently pointed out as a good indicator of the conservation status of riparian forests of the Guadalquivir river, Spain [26] They are influenced by a more complex suite of environmental variables, for instance than plants, and for a highly dynamic and vulnerable ecosystem, as the riparian corridors, ant metrics may be favorably sensitive to acute impacts of short-term events [12,42]. Ant species are often classified into functional groups (FG), transcending taxonomic boundaries, reducing the apparent complexity of ecological systems and allowing comparisons between communities [54,55] Despite their global-scale responses to environmental stress and disturbance, classifications should be established for specific regions, and caution must be taken in extrapolating the results to a global scale [54,56]. At the same time, clarifying the extent to which metrics based on ant responses provide useful information that cannot be provided by traditional physical and structural indicators
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
