School of Biological Sciences, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UU, UK.
Department of Ecology, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
Ecol Lett. 2018 May;21(5):713-723. doi: 10.1111/ele.12939. Epub 2018 Mar 13.
Partitioning of soil phosphorus (P) pools has been proposed as a key mechanism maintaining plant diversity, but experimental support is lacking. Here, we provided different chemical forms of P to 15 tree species with contrasting root symbiotic relationships to investigate plant P acquisition in both tropical and subtropical forests. Both ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) trees responded positively to addition of inorganic P, but strikingly, ECM trees acquired more P from a complex organic form (phytic acid). Most ECM tree species and all AM tree species also showed some capacity to take up simple organic P (monophosphate). Mycorrhizal colonisation was negatively correlated with soil extractable P concentration, suggesting that mycorrhizal fungi may regulate organic P acquisition among tree species. Our results support the hypothesis that ECM and AM plants partition soil P sources, which may play an ecologically important role in promoting species coexistence in tropical and subtropical forests.
土壤磷（P）库的分区被认为是维持植物多样性的关键机制，但缺乏实验支持。在这里，我们向 15 种具有不同根共生关系的树种提供了不同形式的 P，以研究热带和亚热带森林中的植物 P 吸收。外生菌根（ECM）和丛枝菌根（AM）树对无机 P 的添加都有积极的反应，但引人注目的是，ECM 树从复杂的有机形式（植酸）中获取更多的 P。大多数 ECM 树种和所有 AM 树种也显示出一定的能力从简单的有机 P（单磷酸盐）中吸收。菌根定殖与土壤可提取 P 浓度呈负相关，这表明菌根真菌可能调节树种间的有机 P 吸收。我们的结果支持 ECM 和 AM 植物对土壤 P 来源进行分区的假设，这可能在促进热带和亚热带森林中物种共存方面发挥重要的生态作用。
