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.

该奖项根据 2009 年美国复苏和再投资法案（公法 111-5）提供资金。 生态专业化是物种适应特定环境的过程，对于理解生物多样性的两个重要驱动因素：物种形成（新物种的进化）和灭绝至关重要。土壤专家或仅出现在特定土壤类​​型上的物种对整体生物多样性做出了巨大贡献。在加利福尼亚州，蛇纹土露头（重金属浓度高，植物必需养分浓度低）仅占土地的 1%，但包含该州植物类群的 14%（312 个类群）。对压力基质的适应解释了为什么在这些基质上发现了植物物种，但并不能解释为什么这些物种仅限于它们。一种假设表明，对奇怪基质的适应会降低在更典型基质上生存的能力，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殖民更常见的土壤栖息地。拟议工作的目标是评估土壤成分、食草动物和植物竞争者的组合选择是否产生了仅限于压力基质的物种。将对芥菜科链霉菌属物种的土壤特性、不同基质上的生长情况以及与食草动物和植物竞争者的相互作用进行测量。分析中将考虑物种之间的进化关系，以深入了解过去的物种形成事件及其与蛇纹土适应的关系。链霉菌属的几种物种被列为稀有或濒危物种。将创建一个网站，其中包含有关土壤和这些植物物种生命各个阶段（种子到果实）的信息。这些信息对于土地管理者调查这些植物的种群很有用。其中一些土壤专家具有独特的特性，例如在叶子中超积累金属的能力，并已被用于回收金属污染的土壤和进行植物采矿，因此这项研究将更好地为此类生物修复工作提供信息。培养本科生、研究生和技术人员。