Individual Function and Community Processes in Desert Annuals

本研究旨在探讨索诺兰沙漠冬季一年生植物的功能生物学，以了解其种群和群落动态。 一年生植物是干旱区植物群落的重要组成部分。 生态学家感兴趣的机制，使物种共存，从而保持物种多样性。 我们以前记录了长期的人口和社区的索诺兰沙漠一年生植物的社区动态。 这个生态系统的降水量变化很大。 植物以物种特异性的方式对这种变异性做出反应，从而导致生殖成功的特异性时间表。 这种部分不相关的繁殖以现在数学上理解的方式促成了这些物种的共存。 该提案的目标是了解物种之间的这种性能差异，这有助于它们的共存，是它们的生理学和形态学的函数。 我们会收集植物在自然环境中生长的各种生理、形态和稳定同位素数据。这将揭示功能生物学的变化，决定不同的共存物种如何经历环境变化，从而共存。以前收集的长期人口动态数据，这个社区给了我们一个独特的窗口，环境变化如何有助于生物多样性的脱钩的时间模式的繁殖成功。这个项目使我们能够解释潜在的生物学，它创造了对变化的不同反应，而这种反应反过来又导致了两个重要的生态现象：物种共存和多样性。这项工作的结果也与沙漠系统的管理计划密切相关。

This proposal is to investigate the functional biology of Sonoran Desert winter annual plants in order to provide insights into their population and community dynamics. Annual plants are a major component of arid land plant communities. Ecologists are interested in the mechanisms that allow species to coexist and hence maintain species diversity. We have previously documented long-term population and community dynamics of a community of Sonoran Desert annuals. This ecosystem has highly variable precipitation. Plants respond to this variability in species-specific ways that result in the idiosyncratic schedules of reproductive success. This partially uncorrelated reproduction contributes to these species coexistence in ways that are now understood mathematically. The goal for this proposal is to understand how this variation in performance among species, which contributes to their coexistence, is a function of their physiology and morphology. We will collect various types of physiological, morphological and stable isotope data on plants growing in their natural habitats. This will uncover variation in functional biology that determines how different co-occurring species experience environmental variation and hence coexist. The previously collected long-term population dynamic data on this community have given us a unique window on how environmental variation can contribute to biodiversity by decoupling the temporal pattern of reproductive success. This project allows us to explain the underlying biology that creates the differential response to variation that is in turn responsible for two important ecological phenomena: species coexistence and diversity. The results of the work are also germane to management plans for desert systems.