From plant traits to plant communities

这一建议涉及的研究（一）如何不同的植物性状是相互关联的物种之间进行比较时，（二）如何不同的价值观的植物性状决定如何以及他们可以生存，生长和繁殖在一个给定的环境中，（三）如何不同的环境将选择不同的性状值和（四）这一过程如何决定植物物种的组装成生态群落。 不同的植物种类和不同类型的植物是不同生境的典型。植物生态学的一个重要但尚未实现的目标是预测在不同的地点和环境中，哪些物种将占优势，哪些物种将处于从属地位，哪些物种将不存在（群落“集合”）。 我已经开发了一个数学模型，旨在预测这种现象，并了解它是如何在不同环境中作为性状选择的结果出现的。 该统计模型（“CATS”）将植物功能性状、环境变量和区域物种库联系起来，以产生相对丰度的定量预测。 在接下来的5年里，我的团队将使用魁北克南部落叶林的林下植物群落来改进CATS，这些植物群落在农业“海洋”中以岛屿的形式存在，并且在大小、隔离和年龄方面都有所不同。 在这个系统中，群落聚集的三种主要力量（扩散限制、基于性状的选择和人口统计随机性）应该特别强大。 我们还将测试一个假设，其目的是解释因果起源的一个众所周知的和非常普遍的模式，叶性状之间的协变，“全球叶经济谱”。 这一假说解释了这种模式作为一个后果的“设计约束”如何构建维管植物的叶子。 最后，我和我的学生将改进和测试一种新的方法，量化一种重要的环境选择因子（土壤肥力），这是植物生态学中的一种基本环境选择因子。

This proposal concerns research into (i) how different plant traits are related to each other when comparing between species, (ii) how different values of plant traits determine how well they can survive, grow and reproduce in a given environment, (iii) how different environments will select for different trait values and (iv) how this process determines the assembly of plant species into ecological communities. Different*plant species, and different types of plants, are typical of different*habitats. An important, and unattained, goal of plant ecology is to predict*which species will be dominant, which will be subordinate, and which will be*absent, in different sites and environments (community “assembly”). I have developed a mathematical model designed to predict this phenomenon and*to understand how it arises as a consequence of trait selection in different environments. This*statistical model (“CATS”) links plant functional traits, environmental*variables, and regional species pools to produce quantitative predictions of*relative abundance. In the next 5 years*my team will refine CATS using the understory plant communities of*deciduous woods in southern Quebec, which exist as islands in an agricultural “sea”*and that differ in terms of size, isolation and age. In this system the three main forces of*community assembly (dispersal limitation, trait-based selection, and*demographic stochasticity) should be especially strong. We will also test an hypothesis which purports to explain the causal origin of a well-known and very general pattern of covariation between leaf traits, the “worldwide leaf economic spectrum”. This hypothesis explains this pattern as a consequence of "design constraints" on how leaves of vascular plants are constructed. Finally, my students and I will refine and test a new*method of quantifying one important environmental selection agent (soil*fertility) which is a fundamental environmental selection agent in plant ecology.