基于尖峰岭热带山地雨林大型固定样地的菌根共生网络结构及其形成机制研究

Tropical rainforests, having the highest biodiversity and the most complex community structure on land, are among the most threatened ecosystems globally. Therefore, mechanisms maintaining species diversity in tropical rainforests are of great concerns in ecological research. Biological mutualistic interaction networks showed some common structural features which are essential to species coexistance. Mutualistic interactions between fungi and plants are diverse and complex in tropical forests. However, little is known about how these complex interaction networks contribute to species coexistance in tropical rainforest ecosystem. This project will investigate diversity and community structure of mycorrhizal fungi interacting with host plant in a permanent plot of tropical montane rainforest which is common and unique to Hainan island by high-throughput pyrosequencing and DNA barcoding. Structural feature of mycorrhizal fungus-plant interaction networks can be characterized by quantifying network indices; and maintenance mechanism of mycorrhizal interaction networks will be characterized by analysis of correlationship between network indices and environmental variables, between network indices and plant phylogeny, and between network indices and functional traits of mycorrhiza. The results are essential to understand the maintenance of biodiversity in tropical rainforest ecosystems, and will provide theoretical and practical insight into the activities of biodiversity conservation and ecological restoration in tropical montane rainforest of Hainan island, China.

热带雨林是生物多样性最高、结构最复杂的森林生态系统，同时也是世界上物种受威胁程度最高的生态系统，因此热带雨林生物多样性维持机制是研究的热点。生物共生网络的普遍性结构对物种共存有重要作用。热带雨林中较高的菌根真菌与植物多样性使菌根的种间互作网络极其复杂，然而尚不清楚这一复杂的菌根共生网络结构如何影响物种共存。本项目以海南尖峰岭热带山地雨林大型固定样地为依托，采集宿主植物根系，用高通量DNA测序和DNA条形码技术检测丛枝菌根与外生菌根真菌的物种组成，以揭示海南独特的热带山地雨林菌根真菌多样性；应用网络分析法揭示菌根真菌与植物间相互作用的共生网络结构特性；通过分析网络结构指标与大样地环境因子、宿主植物系统进化、菌根功能性状的相关性，阐明菌根共生网络结构的形成机制。研究结果既可揭示热带雨林生态系统物种共存与稳定性维持机制，也有助于指导海南热带山地雨林生态系统的生物多样性保护，以及受干扰生境的恢复。

热带雨林是生物多样性最高、结构最复杂的森林生态系统，同时也是世界上物种受威胁程度最高的生态系统，因此热带雨林生物多样性维持机制是研究的热点。生物共生网络的普遍性结构对物种共存有重要作用。热带雨林中较高的菌根真菌与植物多样性使种间互作网络极其复杂，然而尚不清楚这一复杂的菌根共生网络结构如何影响物种共存。本项目以海南尖峰岭热带山地雨林大型固定样地为依托，采集宿主植物根系，采用真菌DNA 条形码技术及测序技术检测丛枝菌根与外生菌根真菌的物种组成，以揭示海南独特的热带山地雨林菌根真菌多样性；应用网络分析法揭示菌根真菌与植物种间互作的共生网络结构特性；通过分析网络结构指标与大样地环境因子、宿主植物系统进化、菌根功能性状的相关性，阐明菌根共生网络结构的形成机制。研究结果既可揭示热带雨林生态系统物种共存与稳定性维持机制，也有助于指导海南热带山地雨林生态系统的生物多样性保护，以及受干扰生境的恢复。