Research on the dynamics of vegetation distribution in relation to past climate can provide valuable insights into terrestrial ecosystems’ response to climate change. However, paleoenvironmental data sources are often scarce. The integration of ecological niche modeling and paleoecological data can fill in this knowledge gap. In order to elucidate the potential impacts of past and future climate change on the distribution of multiple vegetation types, we used 433 occurrence points of 100 species to build distribution models of five vegetation types occurring in southern Brazil, based on past, current, and future scenarios. Past models indicated the existence of a steppe domain during the Last Glacial Maximum, with forest expansion during the Mid-Holocene, which is consistent with paleoenvironmental data. The current distribution model identified a large area that was climatically suitable for ecotones in an important protection area threatened by agribusiness. The optimistic projections for 2070 predicted an expansion of mixed ombrophilous and seasonal semi-deciduous forests to a higher altitude and latitude, respectively. The pessimistic projections predicted a catastrophic scenario, with the extinction of the steppe and the savanna and a major increase of areas unsuitable for all vegetation types. The ombrophilous dense forest remained stable in all time scenarios, even in the pessimistic future projection. The results of the present study reinforce the need for the implementation of policies that will reduce greenhouse gas emissions that drive global climate change, which may lead to the extinction not only of species but also of landscapes as we know them today.

中文翻译：

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气候变化改变了巴西南部热点地区的植被类型分布

对与过去气候相关的植被分布动态的研究可以为陆地生态系统对气候变化的响应提供有价值的见解。但是，古环境数据源通常很少。生态位建模与古生态数据的整合可以填补这一知识空白。为了阐明过去和未来气候变化对多种植被类型分布的潜在影响，我们基于过去，现在和将来，使用433种100种物种的发生点，建立了巴西南部五种植被类型的分布模型。场景。过去的模型表明，在上一次冰期末期存在草原域，而在全新世中期森林扩展，这与古环境数据一致。当前的分配模型确定了一个大面积地区，该地区在农业综合企业所威胁的重要保护区内气候适宜于过渡带。对2070年的乐观预测预测，混交林和季节性半落叶林分别会扩展到更高的海拔和纬度。悲观的预测预示着灾难性的情况，草原和稀树草原的灭绝以及不适合所有植被类型的面积的大幅增加。杂草丛生的森林在所有情况下都保持稳定，即使在悲观的未来预测中也是如此。本研究的结果进一步表明，需要实施旨在减少导致全球气候变化的温室气体排放的政策，