Estrutura da comunidade de macroinvertebrados associados ao folhiço submerso de remanso e correnteza em igarapés da Amazônia Central

Abstract

Rezende, C.F. Community structure of macroinvertebrates associated with leaf litter from riffles and pools from Central Amazon streams. Biota Neotrop. May/Aug 2007 vol. 7, no. 2 http://www.biotaneotropica. org.br/v7n2/pt/abstract?short-communication+bn01607022007 ISSN 1676-0603.Considering that the composition and distribution of freshwater macroinvertebrates is related to several environmental factors, especially water flow and type of substratum I hypothesized that composition, richness and abundance of macroinvertebrates that occur in both environments with distinct hydrological characteristics (riffle and pool) were different between these areas. Specimens were sampled in three streams where five traps were arranged in stretches from pools and riffles totalizing 30 traps. In the laboratory the macroinvertebrates were identified to family level. An analysis of variance in blocks was made in order to verify possible effects of habitat and stream type on the richness and abundance of macroinvertebrates. Shannon´s diversity index was applied, followed by a t-test. The Bray-Curtis cluster analysis was performed to verify the similarity between different habitats. A total of 132 specimens were collected, 97 in riffles and 35 in pools. Among sixteen families collected, six colonized only riffles, two colonized only pools and eight colonized both environments. An effect of the habitat (pools or riffles) upon the richness and abundance of macroinvertebrates was detected. On the contrary, no difference was found among streams (igarapés). The Shannon diversity index was higher in riffles than in pools. The riffle stretches formed a single group on the Bray-Curtis cluster analysis. I conclude that composition and abundance were distinct between the community of macroinvertebrates of riffles and pools. The explaining hypothesis for these results is that the community structure of both environments is distinct due to variations associated with water flow, that allows the existence of groups with different ecological and behavioral features.Keywords: colonization, water flow, aquatic invertebrates. ResumoRezende, C.F. Estrutura da comunidade de macroinvertebrados associados ao folhiço submerso de remanso e correnteza em igarapés da Amazônia Central. Biota Neotrop. May/Aug 2007 vol. 7, no. 2 http:// www.biotaneotropica.org.br/v7n2/pt/abstract?short-communication+bn01607022007 ISSN 1676-0603.Considerando que a composição e a distribuição de macroinvertebrados de água doce é relacionada a diversos fatores ambientais, destacando-se a velocidade da corrente e o tipo de substrato tive como hipótese de trabalho que a composição, riqueza, e abundância de macroinvertebrados que ocorrem em dois ambientes com características hidrológicas distintas (correnteza e remanso) fossem diferentes entre essas áreas. A amostragem foi realizada em três igarapés onde foram dispostas cinco armadilhas em trechos de remanso e cinco em correnteza, totalizando 30 armadilhas. No laboratório os macroinvertebrados foram identificados em ordens e ...

The influence of physical instream spatial variability on Chironomidae (Diptera) assemblages in Neotropical streams

“…Streams normally present high macroinvertebrate abundance associated to riffles (Kikuchi and Uieda, 1998;Kobayashi and Kagaya, 2002;Buss et al, 2004;Rezende, 2007). On the other hand, in this paper, Chironomidae abundance was similar in both mesohabitats and differently than expected.…”

The influence of environmental variables on the functional structure of headwater stream fish assemblages: a study of two tropical basins in Central Brazil

“…The substrate preference was the substrate where the species had higher frequency of occurrence. Foraging locality was determined according to streams velocity, and we considered streams with water velocity superior to 20 cm/s as running waters (riffles) while streams under this limit as standing waters, slower pools (see Rezende, 2007). The other functional traits were obtained from specialized literature (Melo, 2011) and an on-line database for fishes (Froese & Pauly, 2014).…”

Distribuição espacial das guildas tróficas e estruturação da comunidade de Ephemeroptera (Insecta) em córregos do Cerrado de Mato Grosso, Brasil

“…Rezende (2007), por exemplo, ao trabalhar em córregos da Amazônia Central, concluiu que a composição de macroinvertebrados, assim como a abundância, é um parâmetro que pode estar associado ao fluxo da correnteza, uma vez que seriam necessários grupos com exigências ecológicas e comportamentais distintas nos ambientes de acordo com a velocidade da água.…”