Faculty of Sciences, Agostinho Neto University, Av. 4 de Fevereiro 71, Luanda, CP 815, Angola.
Biodiversity, Evolution and Ecology of Plants, Institute of Plant Science and Microbiology, University of Hamburg, Ohnhorststr. 18, Hamburg, 22609, Germany.
New Phytol. 2021 Apr;230(2):510-520. doi: 10.1111/nph.17168. Epub 2021 Feb 21.
The miombo region in Africa is covered by a mosaic of woodlands and geoxylic grasslands and is subject to disturbances such as fires, frost and drought, and low nutrient availability. The dominance of Fabaceae Detarioideae species in miombo ecosystems is remarkable but little understood. We therefore compared plant functional traits (PFTs) of common woody species of the Angolan plateau, grouped by life form (trees, geoxyles), lineage (Fabaceae: Detarioideae, non-Detarioideae) and symbiont association (ectomycorrhiza, rhizobia). PFTs reflect group-specific adaptations to prevalent environmental conditions. To analyse the impact of environmental drivers, we selected PFTs reflecting ecophysiological aspects of leaf morphology, nutrient content and water transport. Traits were measured following standardized protocols. We found differences in key PFTs between trees and geoxyles reflecting both life form-specific adaptations to environmental conditions and lineage-specific strategies to cope with environmental stresses. We interpret higher leaf thickness and higher wood density of geoxyles as responses to harsher open environments. Fabaceae in general and ectomycorrhizal species showed better nutrient status. Symbiotic associations of detarioid legumes with ectomycorrhiza show specific advantages for phosphorous uptake as compared to Rhizobia-associated Fabaceae and to non-Fabaceae and thus may be crucial for the stunning dominance of Detarioideae in miombo landscapes.
非洲的米奥诺米布地区覆盖着林地和钙质草原的镶嵌体，并受到火灾、霜冻和干旱以及养分供应不足等干扰。豆科金合欢族物种在米奥诺布生态系统中的优势非常显著，但了解甚少。因此，我们比较了安哥拉高原常见木本物种的植物功能性状（PFTs），这些物种按生活型（树木、钙质植物）、谱系（豆科：金合欢族、非金合欢族）和共生体关联（外生菌根、根瘤菌）进行分组。PFTs 反映了对普遍环境条件的特定适应。为了分析环境驱动因素的影响，我们选择了反映叶片形态、养分含量和水分运输的生理生态方面的 PFTs。按照标准化方案测量特征。我们发现树木和钙质植物之间的关键 PFTs 存在差异，这反映了对环境条件的特定生活型适应以及对环境压力的特定谱系策略。我们将钙质植物的较高叶片厚度和较高木材密度解释为对更恶劣的开阔环境的反应。豆科植物一般和外生菌根物种表现出更好的养分状况。与根瘤菌相关的豆科植物相比，金合欢族豆科植物与外生菌根的共生关联显示出对磷吸收的特定优势，因此对于金合欢族在米奥诺布景观中的惊人优势可能至关重要。
