Fundamental drivers of plant spectral diversity

植物光谱多样性的基本驱动因素

• 批准号: RGPIN-2019-04537
• 负责人: Laliberté, Etienne
• 金额: $ 4.01万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=737689
• 关键词: Fundamental; drivers; plant; spectral; diversity

Plant spectral diversity -how leaves of plant species differentially interact with solar radiation- is a highly promising but still largely unknown facet of biodiversity. Plant spectral diversity is of high interest because it can be directly remotely sensed, and because it is a powerful integrator of plant phylogenetic and functional diversity. As a result, a new field called "spectranomics" is revolutionizing how we acquire high-resolution biodiversity data over large regions. However, we still know little about the basic drivers of leaf spectral variation across species and environments. The overall objective of my research program is to determine the fundamental drivers of leaf spectral variation within and among plant species, communities, and across soil fertility gradients. The proposed research program builds from my previous Discovery Grant in trait-based plant ecology along natural soil fertility gradients, and develops exciting new research directions about spectral diversity and its linkages with phylogenetic and functional diversity. The central hypothesis is that leaf spectral variation is primarily determined by phylogeny, and secondarily by the environment. The research program is organised around three shorter-term objectives. In the first objective, I will identify fundamental axes of leaf spectral variation among species. Here, I will test the hypothesis that spectral variation is organised along three major axes expressing: (1) the leaf economics spectrum, (2) a trade-off between chemical and structural defences, and (3) a leaf hydraulics spectrum. To do so, I will conduct a large-scale field survey of spectra and traits for a large number of canopy plant species spread across broad edaphic and climatic gradients, using our network of soil chronosequences in Australia. My second objective is to quantify the degree of spectral plasticity within plant species. Specifically, I will test the hypothesis that species with broader edaphic niches show higher spectral plasticity. To do so, I will use a combination of field observations along long-term soil chronosequences and common garden experiments spanning large soil fertility gradients to provide the most comprehensive and rigorous quantification of leaf spectral plasticity to date. Finally, my third objective is to determine the drivers of leaf spectral diversity within and among communities across fertility gradients. In particular, I will test the hypothesis that community-level shifts in spectral diversity across soil fertility gradients express changes in plant taxonomic and functional diversity. This research will be conducted along the Jurien Bay soil chronosequence in Australia, which is one of the strongest natural soil fertility gradients ever described. By unravelling the fundamental drivers of leaf spectral variation across plant species and environments, my research will pave the way for a future global biodiversity observatory informed by spectranomics.

植物光谱多样性--植物物种的叶子如何与太阳辐射发生差异性的相互作用--是生物多样性的一个非常有前途但在很大程度上仍然未知的方面。植物光谱多样性是植物系统发育和功能多样性的重要组成部分，可以直接进行遥感观测。因此，一个名为“光谱学”的新领域正在彻底改变我们获取大区域高分辨率生物多样性数据的方式。然而，我们仍然知道的叶光谱变化的基本驱动程序跨物种和环境。我的研究计划的总体目标是确定叶光谱变化的基本驱动因素内和植物物种之间，社区，和跨土壤肥力梯度。拟议的研究计划建立在我以前的发现补助金在性状为基础的植物生态学沿着自然土壤肥力梯度，并开发令人兴奋的新的研究方向光谱多样性及其与系统发育和功能多样性的联系。中心假设是，叶光谱变化主要是由生育，其次是由环境。该研究计划围绕三个短期目标组织。在第一个目标中，我将确定物种间叶光谱变化的基本轴。在这里，我将测试的假设，光谱变化是有组织的沿着三个主轴表示：（1）叶经济谱，（2）化学和结构防御之间的权衡，（3）叶水力学谱。为此，我将利用我们在澳大利亚的土壤年代序列网络，对分布在广泛的土壤和气候梯度上的大量冠层植物物种的光谱和性状进行大规模实地调查。我的第二个目标是量化植物物种内光谱可塑性的程度。具体来说，我将检验这样的假设：具有更广泛土壤生态位的物种表现出更高的光谱可塑性。要做到这一点，我将使用一个组合的实地观察沿着长期的土壤时序和常见的花园实验跨越大土壤肥力梯度，提供最全面和最严格的量化叶光谱可塑性。最后，我的第三个目标是确定叶光谱多样性的驱动程序内和社区之间的生育梯度。特别是，我将测试的假设，在整个土壤肥力梯度的光谱多样性社区水平的变化表示在植物分类和功能多样性的变化。这项研究将沿着澳大利亚的朱里恩湾土壤时序进行，这是有史以来最强的自然土壤肥力梯度之一。通过揭示植物物种和环境中叶光谱变化的基本驱动因素，我的研究将为未来的全球生物多样性观测站铺平道路。