Habitat architecture influencing microcrustaceans composition: a case study on freshwater Cladocera (Crustacea Branchiopoda)

Abstract

Environmental complexity is considered a key factor for diversity enhancement in aquatic ecosystems. Macrophyte stands are a major contributor for this complexity due to their differential architectures. Nevertheless, the influence of distinct aquatic habitat architectures (with different types of macrophytes or without them) on microcrustaceans' taxa composition, usually found in macrophyte colonized water bodies, is underexplored in limnological studies. The main objective of this study was to analyze this influence by comparing the Cladocera composition among four habitat architectures: (1) fluctuant macrophytes, (2) rooted emergent macrophytes, (3) submerged macrophytes and (4) the limnetic zone of oxbow lakes associated to a large subtropical reservoir. Wide compositional variation was observed. Fluctuant macrophytes exhibited the richest Cladocera assemblage, dominated by Chydoridae. Submerged and rooted emergent macrophytes had the most similar assemblages between them. The most distinctive fauna was found in the limnetic zone, dominated by Bosminidae. Probable differences in resource availability in each sampled habitat architecture are considered as the driving factor for the Cladocera composition variation. We concluded that for a complete inventory of a given local fauna, it is imperative to take into account the aquatic habitat architecture, including macrophyte stands, in the data sampling design.

Influence of Eichhornia crassipes (Mart) Solms on a Tropical Microcrustacean Community Based on Taxonomic and Functional Trait Diversity

“…For submerged aquatic vegetation (SAV), the increase in zooplankton biomass and functional diversity was also related to the increased availability of habitats and ecological niches provided by submerged macrophyte structures [39]. Increased abundance of organisms in the macrophyte mesocosms with the attached feeding type, benthic habitat preference, as well as the herbivore-detritivore trophic grouping together reflects their feeding strategy consisting of scraping the surfaces of submerged branches of macrophytes for periphyton or accumulated detritus on macrophyte roots [3].…”

“…In aquatic ecosystems, the presence of macrophytes has important structuring consequences for microcrustacean communities because their physical characteristics alter habitat structure in ways that can influence resource availability and resource quality [1,2]. It has been reported that for cladocerans, the habitat architecture is an important factor influencing composition [3]. For example, macrophytes increase the availability of attachment surfaces for species that require a substrate for locomotion such as benthic cladocerans, or for species able to use submerged structures to settle and filter water from a stationary position.…”

“…For example, macrophytes increase the availability of attachment surfaces for species that require a substrate for locomotion such as benthic cladocerans, or for species able to use submerged structures to settle and filter water from a stationary position. Macrophytes can increase resources for detritivores because their submerged structures accumulate sediments or detritus [3]. Moreover, macrophytes can also offer a novel prey source for omnivorous or carnivorous microcrustaceans because of increases in associated microorganisms [4].…”

“…Such changes that indirectly promote resource heterogeneity and higher resource availability may explain greater microcrustacean diversity in littoral zones of aquatic ecosystems, even in the absence of predators, especially where macrophytes are more abundant [6]. Some studies have demonstrated a role for macrophytes as mediators in the interaction between prey and aquatic predators [2][3][4][5][6][7], with zooplankton using plants as a refuge against predation by fish [8,9]. However, zooplankton may also avoid macrophyte areas when fish predation is intense in these areas [7].…”

Analyzing the effects of four submerged macrophytes with two contrasting architectures on zooplankton: A mesocosm experiment

“…Habitat complexity in the freshwater ecosystem plays an important role in the growth and distribution of aquatic organisms (Meerhoff et al, 2007;Debastiani-Júnior et al, 2016). Generally, animal abundance and species richness are considerably higher where submerged macrophytes are present (Hemminga and Duarte, 2000).…”