CAREER: Drought and metacommunity stability in riverine networks

职业：河流网络中的干旱和元群落稳定性

• 批准号: 2047324
• 负责人: Albert RUHI VIDAL
• 金额: $ 89.47万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2047324&HistoricalAwards=false
• 关键词: CAREER; Drought; metacommunity; stability; riverine

The frequency, duration, and severity of droughts is increasing in many regions of the world. Drought can negatively impact riverine ecosystems—particularly if streams that generally flow year-round become intermittent. Climatic droughts can isolate entire portions of the river network, and synchronize fluctuations in abundance of aquatic organisms across large spatial scales. How these isolation and synchronization processes may endanger aquatic species directly, or indirectly by modifying species interactions, remains largely unknown. Here I propose to address this gap by combining long-term monitoring and field experiments in an intermittent river network in Pinnacles National Park, with large-scale modeling of stream biodiversity and hydrology data. This CAREER integrates research and education goals, and will provide students from underrepresented backgrounds with hands-on experience on stream sensor instrumentation, biodiversity sampling, and analysis of time-series data. It will also create an Ecological Drought Collaboratory spanning academic, government, and museum institutions researching drought-related questions.Despite much research on freshwater biodiversity responses to drought, it remains difficult to predict responses at high levels of biological organization (food webs and metacommunities). This is largely because biotic interactions can dampen or amplify impacts of abiotic stress on each species. Moreover, drought may erode the capacity of organisms to disperse and recolonize from other sources (resilience strategists), or to persist locally and bounce back after drying events (resistance strategists). Through a combination of approaches that span spatio-temporal scales and disciplines (metacommunity ecology, stream hydrology, time-series analysis), the investigator will determine the net contribution of drought to metacommunity stability. The specific goals of this project are: (i) understanding the controls of metacommunity stability in streams, with a focus on the relatively understudied mechanisms of drought-driven dispersal limitation and synchrony; (ii) determining to what extent recent climatic droughts, in isolation or in conjunction with human activities, synchronized flow regimes within and across river networks; and (iii) forecasting the vulnerability of U.S. stream invertebrates and fishes to future droughts, considering not only local biotic and abiotic change (temperature and flow) but also network-level shifts in habitat portfolio and connectivity. This work will fill a critical gap in our mechanistic understanding of metacommunity dynamics in dendritic networks, and will help better quantify risk of freshwater biodiversity loss under increasingly-variable climates. Integrated educational objectives targeting undergraduate and graduate students, conservation practitioners, and the public will promote understanding of how biodiversity persists in river networks. This increased understanding should improve conservation outcomes via robust design of environmental flows and habitat restoration actions.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.

世界许多地区干旱的频率、持续时间和严重程度都在增加，特别是当全年流动的河流变得间歇性时，干旱可能会完全隔离部分河网并同步化。水生生物丰度在大空间尺度上的波动仍然很大程度上未知，这些隔离和同步过程如何直接或通过改变物种相互作用间接危害水生物种。该职业将尖峰国家公园间歇性河网的长期监测和现场实验与河流生物多样性和水文数据的大规模建模相结合，将研究和教育目标融为一体，并将为来自弱势背景的学生提供实践经验。它还将创建一个涵盖学术、政府和博物馆机构的生态干旱合作实验室，研究干旱相关问题。尽管对淡水生物多样性进行了大量研究。对于干旱的反应，仍然很难预测高水平的生物组织（食物网和元群落）的反应，这主要是因为生物相互作用可以抑制或放大非生物胁迫对每个物种的影响。此外，干旱可能会削弱生物体的能力。从其他来源分散和重新殖民（弹性战略家），或在干旱事件后在当地持续存在并反弹（抵抗战略家）。学科（元群落生态学、河流水文学、时间序列分析），研究者将确定干旱对元群落稳定性的净贡献。该项目的具体目标是：（i）了解溪流中元群落稳定性的控制。关于干旱驱动的扩散限制和同步机制的研究相对较少；(ii) 确定最近的气候干旱在多大程度上独立于人类活动，以及河流网络内和跨河流网络的同步流量状况； (iii) 预测美国河流无脊椎动物和鱼类对未来干旱的脆弱性，不仅考虑当地的生物和非生物变化（温度和流量），而且考虑栖息地组合和连通性的网络水平变化这项工作将填补我们的一个关键空白。对树突网络中元群落动态的机械理解，将有助于更好地量化日益变化的气候下淡水生物多样性丧失的风险，针对本科生和研究生、保护护士和公众的综合教育目标将促进对树突网络中元群落动态的理解。生物多样性如何在河流网络中持续存在，这种加深的理解应该通过环境流和栖息地恢复行动的稳健设计来改善保护成果。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。 。