Universidade Federal de Santa Maria, Programa de Pós-Graduação em Biodiversidade Animal, Centro de Ciências Naturais e Exatas, Prédio 17, Avenida Roraima, 1000, Bairro Cidade Universitária, Camobi, 97105-900 Santa Maria, RS, Brazil.
Universidade do Planalto Catarinense, Programa de Pós-Graduação Ambiente e Saúde, Av. Castelo Branco, 170, Bairro Universitário, 88509-900 Lages, SC, Brazil.
An Acad Bras Cienc. 2024 Sep 9;96(4):e20230918. doi: 10.1590/0001-3765202420230918. eCollection 2024.
Organisms can respond to environmental gradients from local to landscape features. Aquatic insects are particularly affected by watershed peculiarities due to their dependence on microhabitat conditions. However, these relationships are poorly understood in lotic ecosystems of subtropical grasslands, limiting water resources management and bioassessment proposals. Here, we investigated how local stream environment and variations in landscape types affect the assemblage structure of a bioindicator insect group, face to the spatial proximity of the sampled locations. We sampled immatures of Ephemeroptera, Plecoptera, and Trichoptera in streams along the Brazilian Pampa biome, recording environmental descriptors in different grassland ecosystem types. The structure of aquatic insect assemblages differed across grassland types, with specific dominant genera associated with each landscape. Spatially-structured water physicochemical descriptors explained a significant amount of variation in assemblage data. Our findings suggest that grassland ecosystem type delimitations capture ecological attributes, influencing watershed features important to EPT assemblage structuration. Moreover, we highlight the importance of niche-based process structuring EPT assemblages along grassland ecosystem types of Pampa biome. In addition, we encourage using aquatic insects in bioassessment of lotic waters to assess local and landscape environmental impacts. We strongly recommend considering the grassland ecosystem schedule for water resources management and bioassessment proposals.
生物体能对环境梯度做出响应，从局部到景观特征。由于水生昆虫依赖于微生境条件，因此它们尤其受到流域特征的影响。然而，这些关系在亚热带草原的流水生态系统中还没有得到很好的理解，这限制了水资源管理和生物评估建议。在这里，我们研究了局部溪流环境和景观类型的变化如何影响生物指示昆虫类群的集合结构，同时考虑到采样地点的空间接近度。我们在巴西潘帕生物群落的溪流中采样了蜉蝣目、襀翅目和毛翅目幼虫，记录了不同草原生态系统类型的环境描述符。水生昆虫集合体的结构在草原类型之间存在差异，具有特定的优势属与每个景观相关。基于空间结构的水理化描述符解释了集合体数据中大量的变异。我们的研究结果表明，草原生态系统类型的划分捕捉到了生态属性，影响了对 EPT 集合体结构重要的流域特征。此外，我们强调了基于生态位的过程对潘帕生物群落草原生态系统类型中 EPT 集合体结构的重要性。此外，我们鼓励在流水生物评估中使用水生昆虫来评估局部和景观环境影响。我们强烈建议在水资源管理和生物评估建议中考虑草原生态系统计划。
