Luzuriaga Arantzazu L, Ferrandis Pablo, Flores Joel, Escudero Adrián
Department of Biology and Geology, Rey Juan Carlos University, Móstoles, Madrid, Spain.
Botanic Institute of UCLM, Botanic Garden of Castilla-La Mancha, Avda. de La Mancha, Albacete, Spain.
AoB Plants. 2020 May 25;12(3):plaa020. doi: 10.1093/aobpla/plaa020. eCollection 2020 Jun.
Previous studies found that plant communities on infertile soils are relatively resistant to climatic variation due to stress tolerance adaptations. However, the species assemblies in gypsum soil habitats require further investigation. Thus, we considered the following questions. (1) Do harsher arid conditions determine the characteristics of the species that form plant assemblages? (2) Is the selection of the species that assemble in arid conditions mediated by their ability to grow on gypsum soils? (3) Is the selection of species that assemble in harsher conditions related to phylogenetically conserved functional traits? Perennial plant communities were analysed in 89 gypsum-soil sites along a 400 km climate gradient from the central to southeastern Iberian Peninsula. Each local assemblage was analysed in 30 × 30 m plots and described based on taxonomic, functional (soil plant affinity) and phylogenetic parameters. The mean maximum temperatures in the hottest month, mean annual precipitation and their interaction terms were used as surrogates for the aridity conditions in generalized linear models. In the hottest locations, the gypsophily range narrowed and the mean gypsophily increased at the community level, thereby suggesting the filtering of species and the dominance of soil specialists in the actual plant assemblies. Drier sites had higher taxonomic diversity. The species that formed the perennial communities were close in evolutionary terms at the two ends of the aridity gradient. The mean maximum temperatures in the hottest month had the main abiotic filtering effect on perennial plant communities, which was mediated by the ability of species to grow on gypsum soils, and thus gypsum specialists dominated the species assemblies in the hottest locations. In contrast, the perennial communities on gypsum soils were relatively resistant to changes in precipitation. Our findings suggest that the warmer environmental conditions predicted by global change models will favour gypsum specialists over generalists.
先前的研究发现，由于耐胁迫适应，贫瘠土壤上的植物群落对气候变化相对具有抗性。然而，石膏土生境中的物种组合仍需进一步研究。因此，我们考虑了以下问题。（1）更恶劣的干旱条件是否决定了构成植物组合的物种特征？（2）在干旱条件下聚集的物种选择是否由它们在石膏土上生长的能力介导？（3）在更恶劣条件下聚集的物种选择是否与系统发育保守的功能性状有关？沿着从伊比利亚半岛中部到东南部400公里的气候梯度，在89个石膏土样地中分析了多年生植物群落。每个局部组合在30×30米的样地中进行分析，并根据分类学、功能（土壤植物亲和力）和系统发育参数进行描述。在广义线性模型中，最热月份的平均最高温度、年平均降水量及其交互项被用作干旱条件的替代指标。在最热的地点，嗜石膏性范围变窄，群落水平上的平均嗜石膏性增加，从而表明在实际植物组合中物种被筛选以及土壤专性物种占主导地位。较干燥的地点具有更高的分类多样性。在干旱梯度两端，形成多年生群落的物种在进化上相近。最热月份的平均最高温度对多年生植物群落具有主要的非生物筛选作用，这是由物种在石膏土上生长的能力介导的，因此在最热的地点，石膏专性物种主导了物种组合。相比之下，石膏土上的多年生群落对降水变化相对具有抗性。我们的研究结果表明，全球变化模型预测的更温暖环境条件将有利于石膏专性物种而非泛化物种。
