Universidade Federal Rural de Pernambuco - UFRPE, Departamento de Biologia, Programa de Pós-graduação em Etnobiologia e Conservação da Natureza, Recife, PE, Brasil.
Universidade Estadual da Paraíba - UEPB, Departamento de Biologia, Laboratório de Ecologia Neotropical - EcoTropics, Campina Grande, PB, Brasil.
Braz J Biol. 2023 Oct 30;83:e274577. doi: 10.1590/1519-6984.274577. eCollection 2023.
Understanding the factors influencing variation in the diversity and structure of rich biological communities (e.g., Neotropical upland forests) is essential in the context of climate change. In this study, we examine how environmental filters (temperature, precipitation, and elevation) and distinct habitats (moist upland forests - MUF and dry upland forests - DHF) influence the phylogenetic diversity and structure of 54 tree communities (28 MHF and 26 DHF). We used the standardized effect size (ses) of the metrics phylogenetic diversity (ses.PD), mean pairwise distance (ses.MPD), and mean nearest neighbor distance (ses.MNTD) to quantify changes in tree community diversity and structure. Then, we assessed the relationships of the phylogenetic metrics with the environmental filters as predictors using generalized linear models (GLMs). Our results indicate that increasing temperature negatively affects the phylogenetic indices analyzed, leading to less diverse and more clustered communities. In contrast, increasing precipitation and elevation showed a significant positive relationship with the analyzed indices, directing communities towards greater phylogenetic diversity and random or overdispersed structure. Our findings also reveal that phylogenetic diversity and structure vary with habitat type. For example, while MUFs exhibit higher phylogenetic diversity and random structure, DUFs display lower phylogenetic diversity and clustered structure. In conclusion, our results suggest that the phylogenetic patterns exhibited by upland communities in the semiarid region are strongly related to climatic conditions and the habitat in which they are found. Therefore, if the predicted temperature increases and precipitation decreases in climate change scenarios for the semi-arid region materialize, these communities may face significant biodiversity loss.
理解影响丰富生物群落（如新热带高地森林）多样性和结构变化的因素，在气候变化的背景下至关重要。在本研究中，我们研究了环境过滤器（温度、降水和海拔）和不同生境（湿润高地森林-MUF 和干燥高地森林-DHF）如何影响 54 个树木群落（28 个 MUF 和 26 个 DHF）的系统发育多样性和结构。我们使用标准化效应大小（ses）的指标系统发育多样性（ses.PD）、平均成对距离（ses.MPD）和平均最近邻距离（ses.MNTD）来量化树木群落多样性和结构的变化。然后，我们使用广义线性模型（GLMs）评估了与环境过滤器的关系作为预测因子的系统发育指标。我们的结果表明，温度升高对分析的系统发育指数有负面影响，导致群落多样性降低，聚类增加。相比之下，降水和海拔升高与分析指数呈显著正相关，使群落朝着更大的系统发育多样性和随机或过分散的结构方向发展。我们的研究结果还表明，系统发育多样性和结构随生境类型而变化。例如，虽然 MUF 表现出较高的系统发育多样性和随机结构，但 DUF 表现出较低的系统发育多样性和聚类结构。总之，我们的研究结果表明，半干旱地区高地群落表现出的系统发育模式与气候条件和生境密切相关。因此，如果半干旱地区气候变化预测的温度升高和降水减少的情况成为现实，这些群落可能会面临生物多样性的严重丧失。
