Roles of substrate, herbivory and competition in the generation of edaphic endemics: Experimental and historical approaches

基质、食草和竞争在土壤地方病产生中的作用：实验和历史方法

• 批准号: 0919559
• 负责人: Sharon Strauss
• 金额: $ 59.71万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0919559&HistoricalAwards=false
• 关键词: Roles; substrate; herbivory; competition; generation

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Ecological specialization, the process by which species adapt to a certain environment, has been central to understanding two important drivers of biodiversity: speciation (the evolution of new species) and extinction. Edaphic specialists, or species that only occur on particular soil types, contribute greatly to overall biodiversity. In California, serpentine soil outcrops (with high concentrations of heavy metals and low concentrations of essential plant nutrients) make up only 1% of the land but contain 14% (312 taxa) of the state's plant taxa. Adaptation to stressful substrates explains why plant species are found on these substrates, but does not explain why such species are restricted to them. One hypothesis suggests that adaptation to odd substrates decreases the ability to live on more typical substrates, but many edaphic specialists can grow on common soils when planted. Interactions with other species may thus be preventing edaphic specialists from colonizing more common soil habitats. The goal of the proposed work is to evaluate whether combined selection from soil components, herbivores and plant competitors has generated species limited to stressful substrates. Soil properties, growth on different substrates, and interactions with herbivores and plant competitors will be measured for the species in the genus Streptanthus, members of the mustard family. The evolutionary relationships among the species will be accounted for in the analyses to gain insight into past speciation events and their relationship with adaptation to serpentine soils. Several species of Streptanthus are listed as rare or endangered. A website will be created with information on soils and all stages in the life of these plant species (seeds through fruits). Such information will be useful for land managers in surveying populations of these plants. Some of these soil specialists have unique properties, like the ability to hyperaccumulate metals in their leaves, and have been used to reclaim metal-contaminated soils and for phytomining, thus this research will better inform such bioremediation efforts. Undergraduate, graduate students and technicians will be trained.

该奖项是根据2009年《美国复苏和再投资法案》(公法111-5)提供资金的。生态专门化是物种适应特定环境的过程，是理解生物多样性的两个重要驱动因素的核心：物种形成(新物种的进化)和灭绝。土壤专家，或只出现在特定土壤类型上的物种，对整个生物多样性做出了巨大贡献。在加利福尼亚州，蛇纹石露头土壤(重金属浓度高，植物必需营养素浓度低)只占土地的1%，但包含该州14%的植物分类群(312个分类群)。对有压力的底物的适应解释了为什么在这些底物上发现了植物物种，但没有解释为什么这些物种仅限于它们。一种假设认为，适应奇怪的基质会降低在更典型的基质上生存的能力，但许多土壤专家在种植时可以在普通土壤上生长。因此，与其他物种的相互作用可能会阻止土壤专家在更常见的土壤栖息地定居。这项拟议工作的目标是评估从土壤成分、草食动物和植物竞争对手中进行的联合选择是否产生了仅限于有压力的基质的物种。将测量芥科植物链霉菌属物种的土壤特性、在不同基质上的生长以及与草食动物和植物竞争对手的相互作用。物种之间的进化关系将在分析中考虑，以洞察过去的物种形成事件及其与适应蛇纹岩土壤的关系。链霉属的几个物种被列为稀有或濒危物种。将创建一个网站，提供有关土壤和这些植物物种生命的所有阶段(从种子到果实)的信息。这些信息将有助于土地管理人员对这些植物的种群进行调查。这些土壤专家中的一些人具有独特的性质，如在树叶中超积累金属的能力，并已被用于修复被金属污染的土壤和进行植物修复，因此这项研究将更好地为此类生物修复工作提供信息。将对本科生、研究生和技术人员进行培训。