Effects of landscape factors and hydroperiod on aquatic macroinvertebrates with different dispersal strategies in southern Brazil ponds

Abstract

Ponds represent discrete sites surrounded by a terrestrial landscape that is inhospitable for aquatic macroinvertebrates. Such ecosystems are appropriate for testing the influence of area, isolation, and correlated variables such as habitat diversity and hydroperiod, on aquatic macroinvertebrate communities. We tested three hypotheses in natural and non-impacted ponds located in a matrix of coastal dunes without human interference in southern Brazil: (1) area, habitat diversity, and hydroperiod increase the total macroinvertebrate richness and density, while isolation among ponds decreases the total macroinvertebrate richness and density; (2) the influence of environmental factors depends on the dispersal strategies of macroinvertebrates; and (3) macroinvertebrate composition is determined by the interaction of area, habitat diversity, hydroperiod, and isolation and differs among macroinvertebrates with different dispersal strategies. Fourteen ponds were sampled four times from October 2007 to August 2008 in the Lagoa do Peixe National Park coastline. Our results indicated that the pond area influenced only flying macroinvertebrate richness. The isolation and habitat diversity did not determine the richness, density, and composition of macroinvertebrates (total, flying, and non-flying). The richness, density, and composition of pond macroinvertebrates were determined mainly by hydroperiod. The mosaic created by the variation in pond hydroperiod would provide for a greater number of taxa with distinct dispersal capacities within the landscape. However, temporary ponds have disappeared at an alarming rate and there is a need to promote conservation of wetlands with different hydroperiods in southern Brazil.

The interplay between local and landscape scales on the density of pond‐dwelling anurans in subtropical grasslands

“…For instance, two of the generalist species recorded in this study, Leptodactylus latinasus and L. mystacinus , are abundant in rice cultivation fields in the Pampa biome and may benefit from habitat modifications in Pampa wetlands (Machado & Maltchik, 2010). Biotic homogenization of ponds is an important issue in the SBG, as about 90% of wetlands in southern Brazil are already fragmented (Maltchik, 2003; Maltchik, Costa, Becker, & Oliveira, 2003) and threatened by agricultural expansion (e.g., soy and rice), urban development, pollution, and invasion of pines (Grasel, Mormul, Bozelli, Thomaz, & Jarenkow, 2018; Machado, Drummond, & Paglia, 2008; Maltchik et al, 1996; Moraes, Stenert, Rolon, & Maltchik, 2014).…”

Does taxonomic and numerical resolution affect the assessment of invertebrate community structure in New World freshwater wetlands?

“…Differences in numerical resolution may constitute an especially important issue for the study of community structure in freshwater wetlands because the invertebrate communities are usually numerically dominated by a few taxa such as chironomids, oligochaetes and microcrustaceans (e.g. Kratzer and Batzer, 2007 ; Moraes et al, 2014 ), which are the same taxa that are rarely classified with a fine taxonomic resolution.…”

Pond permanence is a key determinant of aquatic macroinvertebrate community structure in wetlands

“…The influence of hydroperiod on macroinvertebrate communities in non-permanently ponded wetlands is evident not only in prairiepothole wetlands of the NPPR, but globally. For example, research in southern Brazil concluded that hydroperiod affected macroinvertebrate richness, abundance and composition (Moraes, Stenert, Rolon, & Maltchik, 2014). Similarly, hydroperiod has been deemed an important structuring component of macroinvertebrates in Mediterranean climates in both Australia (Sim et al, 2013) and Spain (Boix, Sala, Quintana, & Moreno-Amich, 2004).…”