da Silva Marcos Vinícius Dias, Rosa Beatriz F J V, Alves Roberto G
Laboratory of Benthic Invertebrates, Graduate Program in Behavioral Biological Sciences and Animal Biology, Department of Zoology, Institute of Biological Sciences, Federal University of Juiz de Fora, Rua José Lourenço Kelmer, s/n, Campus Universitário, Juiz de Fora, Minas Gerais, CEP: 36036-900, Brazil.
Laboratory of Benthic Invertebrates, Graduate Program in Ecology, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil.
Environ Monit Assess. 2015 Nov;187(11):714. doi: 10.1007/s10661-015-4926-3. Epub 2015 Oct 29.
Riparian vegetation is one of the most important abiotic components determining the water flow pattern in lotic ecosystems, influencing the composition, richness, and diversity of invertebrates. We have identified whether differences in the structure of the assemblages of invertebrates between riffles and pools may influence the responses of fauna to the effects of land use. In addition, we investigated which fauna metrics are responsible for the differentiation between riffles and pools in streams subject to different land uses. During the dry season of 2012, the main substrates of riffles and pools were sampled (Surber collector) from nine streams within forest, pasture, and urban areas. Principal component analysis (PCA) and Permanova showed differences in the set of environmental variables between streams and mesohabitats. The first PCA axis distinguished the forest and pasture streams from the urban area streams and was related to variables indicative of nutrient enrichment and land use, while the second axis was formed by velocity flow and by the quantities of ultrafine and coarse sand, which distinguished the riffles and pools of the streams. The faunal composition distinguished the streams in pasture and forest areas from the urban streams. Riffles and pools were not concordant in the representation of the invertebrate fauna, indicating the importance of sampling both mesohabitats in the types of streams investigated. The richness, taxonomic composition, and relative abundance of families of Ephemeroptera, Plecoptera, and Trichoptera showed robust responses in riffles to the effects of environmental changes, while in pools, only the richness showed a significant response. It was possibly concluded that riffles were more sensitive in detecting the effects of land use. The information from this study help to understand how the community of invertebrates and the types of habitats in streams may be affected by anthropogenic impacts.
河岸植被是决定流水生态系统水流模式的最重要的非生物成分之一，影响着无脊椎动物的组成、丰富度和多样性。我们已经确定了浅滩和深潭之间无脊椎动物组合结构的差异是否会影响动物群对土地利用影响的反应。此外，我们还研究了在不同土地利用方式的溪流中，哪些动物指标导致了浅滩和深潭之间的差异。在2012年旱季，从森林、牧场和城市地区的九条溪流中采集了浅滩和深潭的主要基质样本（苏伯网采集器）。主成分分析（PCA）和多变量方差分析（Permanova）表明，溪流和中型栖息地之间的环境变量集存在差异。主成分分析的第一个轴将森林和牧场溪流与城市溪流区分开来，并且与指示营养物质富集和土地利用的变量有关，而第二个轴由流速以及超细砂和粗砂的数量构成，它区分了溪流中的浅滩和深潭。动物群落组成将牧场和森林地区的溪流与城市溪流区分开来。浅滩和深潭在无脊椎动物群的代表性方面并不一致，这表明在所研究的溪流类型中对这两种中型栖息地都进行采样的重要性。蜉蝣目、襀翅目和毛翅目昆虫的丰富度、分类组成和科的相对丰度在浅滩中对环境变化的影响表现出强烈的反应，而在深潭中，只有丰富度表现出显著反应。可能得出的结论是，浅滩在检测土地利用的影响方面更敏感。这项研究的信息有助于理解溪流中的无脊椎动物群落和栖息地类型如何受到人为影响。
