Birds are important bioindicators of environmental change and perform essential processes for ecosystem functioning. Afforestation of grasslands may lead to the reduction or loss of specific functions performed by bird species. We investigated the effects of afforestation of grasslands in southeastern South America on taxonomic and functional diversity of birds using multidimensional functional diversity indices. We collected data from bird communities in mosaics of native habitat and in eucalyptus plantations. We recorded taxonomic impoverishment in plantations, but no reduction in functional diversity was found in planted areas. The results demonstrate greater functional redundancy in riparian forest, which may confer greater stability for these communities, while higher values of functional diversity in plantations may indicate quite dynamic and less stable communities from a functional point of view. None of the diet categories were strongly associated with the sampled habitats. Nonetheless, omnivorous and insectivorous bird species were among the first to colonize plantations after cutting. Since the response of species to habitat changes are mediated by their traits, we can infer that, for a group of species, forest plantations are not totally unsuitable. However, to conserve different dimensions of diversity, it is essential to conserve mosaics of native vegetation to maintain bird diversity.

鸟类是环境变化的重要生物指标，并为生态系统的功能执行必不可少的过程。草原绿化可能导致鸟类物种特定功能的减少或丧失。我们使用多维功能多样性指数调查了南美东南部草地的绿化对鸟类分类学和功能多样性的影响。我们从原生栖息地的马赛克和桉树人工林的鸟类群落中收集了数据。我们记录了人工林的分类学贫困状况，但在人工林中未发现功能多样性降低。结果表明，河岸带森林具有更大的功能冗余，可能为这些社区带来更大的稳定性，从功能的角度看，较高的人工林功能多样性值可能表明群落非常活跃，稳定性较差。没有一种饮食类型与所采样的栖息地密切相关。但是，杂食性和食虫性鸟类是砍伐后最早定植在人工林中的物种。由于物种对生境变化的反应是由它们的性状介导的，我们可以推断出，对于一组物种而言，人工林并非完全不合适。但是，为了保护多样性的不同维度，必须保护本地植被的马赛克以维持鸟类的多样性。杂食性和食虫性鸟类是砍伐后最早定植在人工林中的物种。由于物种对生境变化的反应是由它们的性状介导的，我们可以推断出，对于一组物种而言，人工林并非完全不合适。但是，为了保护多样性的不同维度，必须保护本地植被的马赛克以维持鸟类的多样性。杂食性和食虫性鸟类是砍伐后最早定植在人工林中的物种。由于物种对生境变化的反应是由它们的性状介导的，我们可以推断出，对于一组物种而言，人工林并非完全不合适。但是，为了保护多样性的不同维度，必须保护本地植被的马赛克以维持鸟类的多样性。