Species diversity, stability and loss

我的研究阐明了维持生物多样性的基本规律。在这个提案中，我综合了科学文献和我自己的研究的最新进展，以测试关于生物多样性如何维持以及何时丧失的三个主要问题。物种的稳定性是否存在可以通过其丰度或功能特征来预测的特征差异？生态学家早就注意到，大多数群落中的大多数物种都是罕见的，只有少数物种的丰度很高。最近的理论认为，这种稀有度的分布映射了物种如何随时间波动，以及它们从干扰中恢复的可能性。我将此与另一种关于物种所扮演的功能角色的假设进行对比，该假设使用实验诱导的干扰，针对具有不同特征和不同丰度的物种。优势种单一栽培的不稳定性能否解释生物多样性和聚合功能的时间格局？由于物种数量很少而产生的第二个现象是，它们在调节其他物种方面起着主导作用。我建议对限制这些优势物种的过程进行测试，重点关注这种限制的性质如何影响其他物种和生态群落的净功能。营养相互作用和扩散如何以及何时抑制或膨胀物种丰度的随机波动？生态系统被描述为能量的动态运动——生物体以太阳和其他生物体为食，获得能量，然后在消耗或分解时重新分配这些能量。能量的动态转移会对生物多样性产生影响，因为一个物种种群的微小变化会影响到它所消耗的物种和捕猎它的物种，从而导致波动波及整个食物网。我们使用植物中自然隔离的食物网来解决第三个问题，并使用实验方法来测量一个营养水平（例如，滤食性动物）的随机波动如何传播给它们的猎物和捕食者。总之，这些问题测试了一个更大的问题的三个部分，即物种及其提供的服务如何随时间波动，以及这些波动是否可以通过物种的特性和它们之间的相互作用来理解。它们提供的基础科学对于保护生物多样性及其提供的许多服务是必要的。这项研究将在加拿大和哥斯达黎加进行，使用科学实验、数学建模、统计和分子工具。它将培养5名博士研究生、2名硕士研究生，并在资源管理、保护、数据分析和学术界等领域所需的尖端方法方面部分支持一名博士后。

My research elucidates the basic laws that underpin the maintenance of biodiversity. In this proposal, I synthesize recent advances from the scientific literature and my own research to test three overarching questions about how biodiversity is maintained and when it is lost. Are there characteristic differences in the stability of species that can be predicted by their abundances or functional traits? Ecologists have long noted that most species in most communities are rare, with only a few species occurring at high abundances. Recent theory posits that this distribution of rarity maps onto how species fluctuate through time and how likely they are to recover from disturbance. I contrast this with an alternate hypothesis about the functional roles that species perform, using experimentally-induced disturbances that target species with different traits and of different abundances. Can instabilities of monocultures of dominant species explain temporal patterns of biodiversity and aggregate functions? A second phenomenon that arises from having only a few abundant species is that they play a dominant role in regulating other species. I propose a test of the processes that limit these dominant species, with a focus on how the nature of that limitation influences other species and the net functioning of ecological communities. How and when do trophic interactions and dispersal dampen or inflate random fluctuations in species abundances? Ecosystems are described as dynamic movements of energy - organisms feeding off the sun and each other to gain energy and then redistributing that energy as they are consumed or decompose. The dynamic transfer of energy has consequences for biodiversity, as a slight change in the population of one species has impacts on those it consumes and those who hunt it, causing fluctuations to ripple through the food web. We address this third question using naturally isolated food webs that occur in plants, and use an experimental approach to measure how random fluctuations in one trophic level (e.g., filter feeders) propagate to their prey and their predators. Together, these questions test three parts to the larger question of how species and the services they provide fluctuate through time, and whether those fluctuations can be understood through the properties of the species and their interactions. The basic science that they provide is necessary for protecting biodiversity and the many services it provides. The research will be carried out in Canada and Costa Rica, using scientific experiments, mathematical modeling, statistics and molecular tools. It will train five PhD students, two MSc students and partially support a postdoctoral fellow in cutting-edge methods that are needed in fields like resource management, conservation, data analytics, and academia.