Valle I C, Buss D F, Baptista D F
Programa de Pós-graduação em Ciências Ambientais e Florestais, Departamento de Ciências Ambientais, Universidade Federal Rural do Rio de Janeiro - UFRRJ, BR 465, Km 7, CEP 23890-000, Seropédica, RJ, Brazil.
Braz J Biol. 2013 May;73(2):231-8. doi: 10.1590/S1519-69842013000200002.
We assessed two dimensions of stream connectivity: longitudinal (between forest patches along the stream) and lateral (riparian vegetation), using macroinvertebrate assemblages as bioindicators. Sites representing different land-uses were sampled in a lowland basin that holds a mosaic of protected areas. Land-use analysis, forest successional stages and riparian zone widths were calculated by the GIS analysis. Macroinvertebrate fauna was strongly affected by land-use. We observed a continuous decrease in the number of sensitive species, %Shredders and IBE-IOC biotic index from the upstream protected area to highly deforested sites, increasing again where the stream crosses a Biological Reserve. When analysing buffer strips, we found aquatic fauna responding to land-use alterations beyond the 30 m riparian corridor (60 m and 100 m wide). We discussed the longitudinal connectivity between forest patches and the riparian vegetation buffer strips necessary to hold high macroinvertebrate diversity. We recommend actions for the increase/maintenance of biodiversity in this and other lowland basins.
我们使用大型无脊椎动物群落作为生物指标，评估了溪流连通性的两个维度：纵向（沿溪流的森林斑块之间）和横向（河岸植被）。在一个拥有保护区镶嵌体的低地流域，对代表不同土地利用类型的地点进行了采样。通过地理信息系统（GIS）分析计算土地利用分析、森林演替阶段和河岸带宽度。大型无脊椎动物区系受到土地利用的强烈影响。我们观察到，从上游保护区到森林砍伐严重的地点，敏感物种数量、碎食者百分比和IBE-IOC生物指数持续下降，而当溪流穿过一个生物保护区时，这些指标又再次上升。在分析缓冲带时，我们发现水生动物区系对河岸走廊30米以外（60米和100米宽）的土地利用变化有反应。我们讨论了森林斑块与河岸植被缓冲带之间的纵向连通性对于维持高大型无脊椎动物多样性的必要性。我们建议采取行动，以增加/维持该低地流域及其他低地流域的生物多样性。
