植物属性地理的研究进展与展望

Advances and prospects of plant trait biogeography

植物属性地理学是植物地理学的一个新兴研究方向,研究植物属性的地理分布规律。目前与植物属性地理相关的研究热点主要集中在植物属性的多尺度表达、植物属性的权衡关系和属性多样性与生态系统功能三个方面。比叶面积、叶干物质含量、叶氮含量、种子质量、植物高度、茎密度是最受关注的植物属性。植物属性需要在植物个体水平上进行测量,然后基于群落内物种相对优势度的加权平均上推到群落水平。植物属性权衡关系主要包括叶片经济型谱及属性与环境因子之间的权衡关系研究。全球植物属性数据库的丰富与共享,推动着植物属性地理学的蓬勃发展。当前的植物属性空间连续分布主要利用全球属性数据库和空间统计建模方法实现,但借助激光扫描和成像光谱技术直接对区域植物功能属性进行空间制图正成为植物属性地理学空间计算的新方法。植物属性的空间格局分析是植物属性地理学的重要内容之一,不仅有助于解释植物物种的适应性与分布、群落构建等问题,而且为预测全球气候变化对植物的影响提供了依据。用植物属性代替物种可以更好地解释植物分布和植物对环境适应的生理机制,所以在全球植被模型研究中开始尝试将基于物种的植被动态模型发展为基于属性的植被动态模型,这将会给全球变化下碳循环过程的模拟和陆面模式带来新的机遇和挑战。展望未来,植物属性地理学仍然需要发展新的研究手段,深化全球植物属性的空间分异规律及其与环境因子之间的关系研究,以及完善全球和区域植物属性数据库建设。

Plant trait biogeography is an emerging field in plant geography and it is about the geographical distribution of plant traits.At present,there are three hotspots in plant trait research,including performance of traits at multiple levels,trade-offs among traits and the relationship between trait diversity（functional diversity）and ecosystem functioning.Important traits include,for example,specific leaf area,leaf dry matter content,leaf nitrogen concentration,seed mass,plant height and stem density.Traits are measured with individual plants and can be scaled up to the community level（community weighted means and trait diversity）.Trade-offs contain not only the leaf economics spectrum,but also relationships between traits and the environment.The development of global trait database largely enhances the progress of plant trait biogeography.Mapping plant traits mainly relies on the global database and spatial statistical modeling techniques,but a new method using combined laser scanning and imaging spectroscopy has been developed recently to map regional patterns of plant trait diversity.Spatial pattern analysis is an important part of plant trait biogeography.It helps to explain the distribution of plants,plant adaptability and patterns of community assembly,and then provides evidence to predict how global climate changes would influence plants.By examining plant traits instead of species,the physiological mechanisms behind plant adaptability and distribution can be better explained.Therefore,replacing species with plant traits in global vegetation models would bring new opportunities and challenges for global carbon cycle models and land surface models under global climate changes.