Influence of habitat heterogeneity and bed surface complexity on benthic invertebrate diversity in a gravel‐bed river

Abstract

Maintaining or restoring physical habitat diversity is a central tenet of sustainable river management, yet a link between habitat and ecological diversity in fluvial systems has long remained equivocal. The lack of consistent evidence partly reflects the problems of characterizing habitat in ways that are ecologically meaningful. This paper assesses the influence of habitat heterogeneity and complexity on macroinvertebrate assemblages in a mountain gravel‐bed river. With the use of 0.1‐m resolution data obtained from an acoustic Doppler current profiler, heterogeneity and complexity in hydraulic conditions and bed topography were characterized using 13 metrics applied to 30 areas, each 1 m2, with an invertebrate sample collected from each area. Turnover of invertebrate taxa (i.e., β‐diversity) between sampled areas was rather limited, but observed differences in diversity were related significantly to several metrics of habitat heterogeneity. Invertebrate abundance was related to habitat diversity, patch size coefficient of variation, and patch size, whereas the Shannon diversity was related to the number of patches and patch size. None of the habitat complexity metrics accounted for a significant amount of observed variation in invertebrate communities between sampled areas. The paper demonstrates that high‐resolution data can help reveal relationships between habitat and benthic invertebrate diversity.

Monitoring vertebrate biodiversity of a protected coastal wetland using eDNA metabarcoding

“…This result is consistent with the idea that waterborne eDNA accumulates as it passes through rivers and estuaries (Barnes & Turner, 2016;Deiner et al, 2016). However, an increase in biodiversity downstream in riparian and estuarine ecosystems has also been associated with increasing habitat heterogeneity, complexity, and sea connectivity toward river deltas (Béjar et al, 2020;Rice et al, 2006), which can confound the richness accumulation hypothesis discussed here. Nevertheless, the detection of freshwater species such as creole perch (P. trucha)…”

The active layer in gravel‐bed rivers: An empirical appraisal

“…Dépret et al ., 2019; Staentzel et al ., 2020), fluvial ecology (e.g. Kondolf and Wolman, 1993; Gibbins et al ., 2007; Tena et al ., 2013; Haschenburger, 2017; Béjar et al ., 2020), and channel evolution (e.g. Liébault and Piégay, 2002; Comiti et al ., 2011; Liébault et al ., 2013; Vázquez‐Tarrío et al ., 2019b), amongst others.…”

Geomorphology shapes relationships between animal communities and ecosystem function in large rivers

“…mosaics comprised of multiple habitat types) influence biological diversity, we quantified habitat‐weighted sediment size and habitat diversity at 100 m extents across the riverscape. These two metrics were used because they integrate attributes of multiple habitat types into single predictor variables that have been shown to strongly influence invertebrate assemblages (Death and Winterbourn 1995, Rice et al 2001, Brosse et al 2003, Béjar et al 2020). We first calculated habitat‐weighted sediment size and habitat diversity for contiguous 100 m rectangular cross sections.…”