An effective way to access processes of ecological communities and ecosystems is the use of functional traits; therefore, the use of the functional characteristics of diatoms in paleolimnological works has been growing. In this study, the variations in the abundance of functional traits of sedimentary diatoms were evaluated in two lakes (Garças Lake and Patos Lake), from a subtropical floodplain, which present different intensities of influence of dams. Diatom community functional diversity and functional beta decomposed were calculated. A core from each environment was collected and samples of approximately 50 years were used. According to the functional diversity results, the two lakes showed different patterns, with a greater functional variation in Garças Lake. Through functional beta diversity results, the lakes showed similar results. Both showed a reduction in the functional diversity values and substitution of traits, after the 1980s in Garças Lake, and after ~ 2008 in Patos Lake. In these periods, both environments showed dominance of the same functional categories related to high turbulence and lower waters. The results suggest hydrological changes in the two lakes, which may have been driven by dams close to the floodplain.

获取生态群落和生态系统过程的一种有效方式是利用功能特性；因此，硅藻功能特性在古湖泊学工作中的应用越来越多。在这项研究中，对来自亚热带洪泛区的两个湖泊（加斯湖和帕托斯湖）的沉积硅藻功能性状丰度的变化进行了评估，这两个湖泊呈现出不同强度的水坝影响。计算了硅藻群落功能多样性和分解的功能β。收集了来自每个环境的岩心，并使用了大约 50 年的样本。根据功能多样性结果，两个湖泊呈现出不同的格局，加尔萨斯湖的功能变异较大。通过功能性β多样性结果，湖泊显示出相似的结果。在 1980 年代在 Garças 湖和 ~ 2008 年在 Patos 湖之后，两者都显示出功能多样性值和性状替代的减少。在这些时期，两种环境都显示出与高湍流和低水位相关的相同功能类别的主导地位。结果表明，这两个湖泊的水文变化可能是由靠近洪泛区的水坝驱动的。