热带雨林物种、功能和系统发育多样性的关联性及影响因素

Why so abundant plant species grow together in the tropical rainforests? Which factors are dominant? Ecologists and conservation biologists have studied these key questions in community ecology, that is, the mechanisms of coexistence of multi-species by disentangling species diversity, functional diversity and phylogenetic diversity. However, previous researches showed that different results were obtained by the different ways, although these three biodiversity components were related. Therefore, we proposed whether the integrative researches on the relationships and determinants of these three biodiversity components could lead to much more reasonable explainations. To do so, we use a dataset including a globally largest plot, 60 hm2, and 164 satellite plots from small to medium scales in Jianfengling, Hainan Island. This dataset includes the information of vegetation investigation and environmental conditions of all plots. Seven functional traits and four DNA sequences of about 600 species in these plots are also measured. It is aimed to find the key factors which influence the species diversity, functional diversity and phylogenetic diversity. Furthermore, we will perform generalized linear mixed models to learn the mismatch and congruence among the three biodiversity components at different spatial scales. Finally, we will map the spatial distribution of each diversity component in Jianfengling by using a kriging interpolation technique based on the spatial autocorrelation structure of variables. This work will facilitate the solution of multi-species coexistence question in the tropical forests. It will also provide more scientific proofs for the biodiversity conservation and making effective measures for the recovery of disturbed tropical rainforests in the future.

为什么热带雨林存在异常丰富的植物种类？哪些因素起到主导作用？目前，生态学家主要依赖于分析群落的物种、功能和系统发育多样性来探讨这个理论生态学核心问题- - 多物种共存策略及其维持机制。以往研究表明这三种途径两两间具有一定的关联性，但是分别基于这三种途径会产生不同的分析结果。因此，整合这三种途径开展研究能否获得更加科学合理的解释，是本申请要解决的主要科学问题。本研究拟从目前全球最完整的中小地理尺度样地系统（海南岛尖峰岭的60公顷大样地和164个公里网格样地）的植被信息、环境因子及样地内约600个物种的7个功能性状和4个DNA序列数据，分析影响群落的物种、功能和系统发育多样性的关键因子；探索中小地理尺度上三者相互间的关联性；绘制三者在典型热带森林区域的空间分布图。本研究不仅可以加深对热带森林生物多样性维持机制的了解，也为有效地实施生物多样性保护和制定受干扰后生态系统恢复措施提供更充分的依据。

为什么热带雨林存在异常丰富的植物种类？哪些因素起到主导作用？目前，生态学家主要依赖于分析群落的物种、功能和系统发育多样性来探讨这个理论生态学核心问题--多物种共存策略及其维持机制。以往研究表明这三种途径两两间具有一定的关联性，但是分别基于这三种途径会产生不同的分析结果。因此，本项目从这三种途径开展联合研究，以期获得更加科学合理的解释。本研究从目前全球最完整的中小地理尺度样地系统（海南岛尖峰岭的60公顷大样地和164个公里网格样地）的植被信息、环境因子及样地内所有物种的物种多样性、功能多样性和系统发育多样性入手；完善了个体信息、功能性状、系统发育和环境因子4个基本数据库的构建。利用这些数据，分析了不同空间尺度条件下物种丰富度与个体密度关联，及物种多样性空间分布格局的尺度效应；并对单个优势树种白颜树空间分布格局进行了分析，描述了典型热带山地雨林的群落结构特征；还分析了多植物种群共存且生物多样性指数非常高的热带雨林物种自然分布格局及其与环境的关联性；采伐干扰后热带雨林物种多样性的变化规律；也分析了不同环境因子条件下功能多样性和群落系统发育多样性的变化规律；这些结果进一步探讨了生境异质性、密度制约、采伐干扰等如何影响群落的物种、功能和系统发育多样性。接着，本项目尝试回答森林群落中物种多样性、群落系统发育多样性和功能多样性三者间是否存在关联性及其关联程度如何；分析了演替过程中物种多样性与功能多样性的变化、物种多样性与功能多样性的关系；物种多样性与地上生物量的关系、功能多样性与地上生物量的关系、功能性状链接环境变量和地上生物量；以及对物种和系统发育多样性的动态变化进行了分析；构建环境因子-群落物种多样性-群落功能多样性-群落系统发育多样性的一些相关关系模型。最后还绘制物种多样性、群落系统发育多样性和功能多样性三者在典型热带森林区域60 hm2和160 km2尺度上的空间分布图。本研究加深了对热带森林生物多样性维持机制的了解，也提出了一些改进建议为更有效地实施生物多样性保护和制定受干扰后生态系统恢复措施提供依据。