系统发育多样性和系统发育结构在岛屿植物群落保护中的意义:以福建沿海19个岛屿为例

Significance of phylogenetic diversity and phylogenetic structure in conservation of island plant communities with case study on 19 islands along the coast of Fujian Province

为了探讨福建沿海岛屿植物多样性的形成与维持机制,本研究在福建近岸有居民岛屿前期调查资料的基础上,补充部分无居民岛屿植物多样性及环境和人口密度调查数据,从物种多样性和系统发育多样性两方面比较了19个岛屿植物多样性及其影响因素。结果表明,岛屿面积是影响植物物种丰富度(species richness,SR)和Faith系统发育多样性(phylogenetic diversity,PD)最重要的因素,纬度和年均降水量也有一定影响。19个岛屿系统发育结构倾向于聚集,植物群落的构建可能主要受到环境因素和人类活动干扰影响。地理距离对岛屿间植物群落系统发育β多样性的变化影响不显著。建议对PD较高的东山岛、粗芦岛、南日岛、湄洲岛、厦门岛、平潭岛、三都岛进行重点保护,并结合实际情况针对各岛屿功能定位制定保护和开发利用方案。本研究可以为多层次的多样性评价指标应用于岛屿植物多样性评估以及群落构建机制分析提供参考,也可以为岛屿生物多样性保护策略的制定提供理论依据。

To understand the formations of plant diversity and maintenance mechanisms of islands along the coast of Fujian Province,the data of prior expeditions on inhabited islands and of plant diversity,population density and environmental factors from uninhabited islands are explored.The plant diversity and its key influencing factors on 19 islands from both the taxonomic and phylogenetic perspectives are studied.It results that area of island is the main factor influencing species and phylogenetic diversity of island plants besides certain impacts by latitude and average annual precipitation.Phylogenetic structures of plant communities on 19 islands tend to be clustered possibly due to the impacts of environmental changes and human activities.Inter-island geographic distance has no significant effects on phylogenetic beta diversity among plant communities on each island.Islands with higher phylogenetic diversity that should be protected with higher priority include Dongshan Island,Culu Island,Nanri Island,Meizhou Island,Xiamen Island,Pingtan Island and Sandu Island.Conservation and exploitation strategies on islands based on their biodiversity situations and functional positions are proposed.This study can provide not only a valuable model for multi-level diversity assessment and analyses of assembly mechanisms of plant community,but also a theoretic support for conservation management strategies.