Diversity and abundance of the benthic macrofauna in lotic environments from the central region of Rio Grande do Sul state, Brazil

Abstract

Ayres-Peres, L., Sokolowicz, C.C. The benthic fauna plays an important role in the trophic web and the nutrient flow of limnetic environments. This work aimed to study the diversity and abundance of the benthic invertebrates in four watercourses in the central region of the state of Rio Grande do Sul, Brazil. Sampling was done seasonally at each site, with a long-handled net at the margins (banks) and streambed, from November 2001 through September 2002. Margalef richness, Shannon diversity and Pielou evenness indices were applied to the data analysis. A total of 58 families and three other major taxa (Hirudinea, Oligochaeta and Copepoda) of invertebrates were identified. The highest values of diversity and abundance were recorded at the margins of the rivers, in the same pattern found in other tropical and subtropical regions. This is the first inventory of benthic invertebrates from central region of Rio Grande do Sul, which will be important for future studies of the diversity and conservation of this fauna, because human alterations of the environment have already begun.

Composition and diversity of Ephemeroptera (Insecta) nymph communities in the middle section of the Jacuí River and some tributaries, southern Brazil

“…For the State of Rio Grande do Sul, no studies on Ephemeroptera nymph communities have been made. Previous studies concern macroinvertebrate communities of the Rio dos Sinos basin (STERNERT et al, 2002;, of the Rio Tainhas and Rio Taquara (BUENO et al, 2003), all in the northeast of the State, and in streams of the middle Jacuí River basin, in the central part of the State (AYRES-PERES et al, 2006). In this area, ecological studies on the communities of Heteroptera (NERI et al, 2005) and Trichoptera (SPIES et al, 2006) have also been done.…”

Community structure of aquatic insects (Ephemeroptera, Plecoptera, and Trichoptera) in Cerrado streams of Paraguay, Paraná, and São Francisco river basins

“…Several studies have shown a close relationship between macrobenthic communities and habitat components, as well as the implications of this relationship for biomonitoring (Arunachalam et al 1991, Cairns & Pratt 1993, Kerans & Karr 1994, Galdean et al 2000, Marques & Barbosa 2001, Callisto et al 2004, Hodkinson & Jackson 2005, Silveira et al 2006, Ayres-Peres et al 2006, Milesi et al 2009. However, studies conducted in pristine and protected areas in Brazil are rare, despite being fundamentally important for biodiversity management in these areas.…”

Effects of diflubenzuron on associated insect fauna with Anopheles(Diptera: Culicidae) in laboratory, partial-field, and field conditions in the Central Amazon

“…In addition to predatory aquatic insects, breeding sites have benthic insects represented by the orders Diptera (Chironomidae), Ephemeroptera and Trichoptera, which act to recycle nutrients and integrate the trophic chain into the aquatic environment, serving as food for fish, amphibians and birds. (Trivinho-Strixino & Strixino 1995, Ayres-Peres et al 2006.…”