Longitudinal Distribution of the Functional Feeding Groups of Aquatic Insects in Streams of the Brazilian Cerrado Savanna

Abstract

We demonstrate that the distribution of the functional feeding groups of aquatic insects is related to hierarchical patch dynamics. Patches are sites with unique environmental and functional characteristics that are discontinuously distributed in time and space within a lotic system. This distribution predicts that the occurrence of species will be based predominantly on their environmental requirements. We sampled three streams within the same drainage basin in the Brazilian Cerrado savanna, focusing on waterfalls and associated habitats (upstream, downstream), representing different functional zones. We collected 2,636 specimens representing six functional feeding groups (FFGs): brushers, collector-gatherers, collector-filterers, shredders, predators, and scrapers. The frequency of occurrence of these groups varied significantly among environments. This variation appeared to be related to the distinct characteristics of the different habitat patches, which led us to infer that the hierarchical patch dynamics model can best explain the distribution of functional feeding groups in minor lotic environments, such as waterfalls.

Landscape variables influence taxonomic and trait composition of insect assemblages in Neotropical savanna streams

“…Most previous studies addressing species traits have been generally restricted to trophic guilds (e.g. Brasil, Juen, Batista, Pavan, & Cabette, ; De Castro et al., ; Ferreira et al., ). However, the Multiple Trait‐Based (MTB) approach (Dolédec & Statzner, ; Menezes, Baird, & Soares, ) offers more mechanistic understanding than traditional taxonomy‐based approaches for assessing relationships between stream assemblage composition and environmental variables.…”

“…Most previous studies addressing species traits have been generally restricted to trophic guilds (e.g. Brasil, Juen, Batista, Pavan, & Cabette, 2014;De Castro et al, 2016;Ferreira et al, 2017).…”

The effects of environmental integrity on the diversity of mayflies, Leptophlebiidae (Ephemeroptera), in tropical streams of the Brazilian Cerrado

“…The distribution of these patches within the system will determine the composition of local communities. Environmental changes -in particular those related to resource availability (Bispo et al, 2006) and the homogenization of habitats (Ligeiro et al, 2013;Shimano et al, 2013aShimano et al, , 2013b) -will alter the configuration of niches, affecting the demographic capacity of species (Chave, 2004), and changing species richness and abundance within the community resulting from these environmental filters (Buss et al, 2002;Bispo et al, 2006;Dolny´et al, 2012;Brasil et al, 2014).…”

Ecological studies of mayflies (Insecta, Ephemeroptera): Can sampling effort be reduced without losing essential taxonomic and ecological information?

“…Many recent studies in aquatic ecology have investigated broad themes such as changes in the composition of assemblages and functional groups along a longitudinal gradient (from the headwaters to the mouth of a watercourse), while others have evaluated the distribution patterns of macroinvertebrates (Brasil et al 2014), and the organization of communities and their biological features at different scales (Callisto et al 2012). While an increasing number of macroinvertebrate studies are being published, many lacunae persist in the understanding of the ecological characteristics of these organisms, and these require further attention.…”

“…Tonello et al 2014) and functional groups (e.g. Brasil et al 2014). The identification of species is important because different species of the same genus may not always be comparable in their ecophysiological requirements or environmental tolerance (Merritt et al 2007).…”