CAREER: Integrating Neoecological and Paleoecological Approaches to Exploring the Effects of Climate Change on Arthropod Diversity and Community Structure

不断变化的温度和降水模式正在影响世界各地生态系统的结构和功能。到目前为止，大多数研究都集中在个体物种对环境变化的反应上，但关于整个群落在漫长的时间窗口中反应的方向和大小的证据大多尚不清楚。这项研究将结合古生态学和现代生态学来研究节肢动物群落随降水变化的长期动态，降水是构成荒漠系统的主要环境驱动因素。这项研究将重点放在智利阿塔卡马沙漠中保存在化石和当代啮齿动物吸虫(巢穴处的碎屑堆)中的动植物遗骸。干旱环境中的啮齿类蚊子保存着过去5万年来土壤节肢动物群落和环境条件的详细信息。古生态学和现代生态学的结合将拓宽我们对过去和现在生物多样性形成机制的理解。过去和现在的生物多样性变化机制将被用来预测未来降水变化对干旱土地土壤群落的影响。此外，该项目将为本科生和研究生以及博士后提供许多研究和培训机会。美国本科生还将有机会参加智利的野外沙漠生态学课程。该研究项目将使用独特的、未得到充分利用的古生物档案，提供节肢动物土壤群落对不断变化的环境条件的抵抗力和弹性的见解。通过将啮齿动物幼虫的古代和现代生态数据与同位素地球化学相结合，该项目将检验以下假设：(1)弄清土壤节肢动物在时间和空间尺度上的多样性格局；(2)群落一级对降水变化作出反应的机制；(3)古生态记录中偏差的大小和方向。后者是理解过去、现在和未来社区-环境关系的关键前提。在时间尺度内和跨时间尺度(当代、历史和古代)整合数据，并使用这些数据来预测生态群落的变化，需要制定明确的协议和衡量标准。因此，该项目还致力于创建一个用于媒介生态分析的工具箱，以缓解目前媒介数据的一些局限性(例如，时间不连续和混合、攻丝生物学)。这个工具箱将适用于广泛的地理问题，并可转移到其他中期重建，如在索诺兰沙漠的重建。了解生物多样性模式和生态群落沿环境梯度的长期变化可能有助于预测复杂系统对时空尺度气候变化的响应。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Changing temperature and precipitation patterns are affecting the structure and function of ecological systems worldwide. Most studies to date have focused on individual species responses to environmental change, but evidence for the direction and magnitude of whole-community responses, over long temporal windows, remain mostly unknown. This research will integrate paleoecology and modern ecology to study the long-term dynamics of arthropod communities across changes in precipitation, the major environmental driver structuring desert systems. This research will focus on plant and animal remains preserved in fossil and contemporary rodent middens (debris piles at nest sites) in the Atacama Desert in Chile. Rodent middens in arid environments preserve detailed information on soil arthropod communities and environmental conditions over the last 50,000 years. The integration of paleoecology and modern ecology will broaden our understanding of mechanisms shaping past and present biodiversity. Past and contemporary mechanisms underlying biodiversity change will then be used to predict the effects of future precipitation change on arid land soil communities. In addition, the project will provide many research and training opportunities for undergraduate and graduate students, as well as a postdoctoral fellow. US undergraduates will also have the opportunity to participate in a field-based Desert Ecology course in Chile.This research project will use a unique and underutilized paleobiological archive to provide insights about the resistance and resilience of arthropod soil communities to changing environmental conditions. By integrating paleo and modern ecological data from rodent middens with isotope geochemistry, this project will test hypotheses focused on: (i) disentangling soil arthropod diversity patterns across temporal and spatial scales; (ii) mechanisms underlying community-level responses to changes in precipitation; and (iii) the magnitude and direction of biases in the paleoecological record. The latter is a crucial prerequisite for understanding past, present, and future community-environment relationships. The integration of data within and across temporal scales (contemporary, historical, and paleo), and using this data to predict changes in ecological communities, requires development of clear protocols and metrics. Hence, this project also aims to create a toolbox for ecological analyses in middens that mitigates some current limitations of midden data (e.g., temporal discontinuity and mixing, taphonomy). This toolbox will be applicable to a broad range of geographical questions and transferable to other midden reconstructions, such as those in the Sonoran Desert. Understanding long-term variation in biodiversity patterns and ecological communities along environmental gradients may allow responses of complex systems to changes in climate across spatial and temporal scales to be predicted.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.