Silveira M P, Buss D F, Nessimian J L, Baptista D F
Embrapa Environment, Rodovia SP 340, km. 127.5, CEP 13820-000, Jaguariúna, São Paulo, Brazil.
Braz J Biol. 2006 May;66(2B):623-32. doi: 10.1590/s1519-69842006000400006.
Benthic macroinvertebrate assemblages are structured according to physical and chemical parameters that define microhabitats, including food supply, shelter to escape predators, and other biological parameters that influence reproductive success. The aim of this study is to investigate spatial and temporal distribution of macroinvertebrate assemblages at the Macaé river basin, in Rio de Janeiro state, Southeastern Brazil. According to the "Habitat Assessment Field Data Sheet--High Gradient Streams" (Barbour et al., 1999), the five sampling sites are considered as a reference condition. Despite the differences in hydrological parameters (mean width, depth and discharge) among sites, the physicochemical parameters and functional feeding groups' general structure were similar, except for the less impacted area, which showed more shredders. According to the Detrended Correspondence Analysis based on substrates, there is a clear distinction between pool and riffle assemblages. In fact, the riffle litter substrate had higher taxa in terms of richness and abundance, but the pool litter substrate had the greatest number of exclusive taxa. A Cluster Analysis based on sampling sites data showed that temporal variation was the main factor in structuring macroinvertebrate assemblages in the studied habitats.
底栖大型无脊椎动物群落是根据定义微生境的物理和化学参数构建的，这些参数包括食物供应、躲避捕食者的庇护所，以及影响繁殖成功率的其他生物学参数。本研究的目的是调查巴西东南部里约热内卢州马卡埃河流域大型无脊椎动物群落的空间和时间分布。根据“栖息地评估现场数据表——高梯度溪流”（Barbour等人，1999年），这五个采样点被视为参考条件。尽管各采样点的水文参数（平均宽度、深度和流量）存在差异，但除了受影响较小的区域显示出更多的碎食者外，理化参数和功能摄食组的总体结构相似。根据基于基质的去趋势对应分析，潭和浅滩群落之间有明显区别。事实上，浅滩枯枝落叶基质在丰富度和丰度方面有更高的分类单元，但潭枯枝落叶基质有最多的特有分类单元。基于采样点数据的聚类分析表明，时间变化是研究栖息地中大型无脊椎动物群落结构的主要因素。
