NSFDEB-NERC: Warming's silver lining? Thermal compensation at multiple levels of organization may promote ecosystem stability in response to drought

NSFDEB-NERC：变暖的一线希望？

• 批准号: NE/Y00549X/1
• 负责人: Mark Ledger
• 金额: $ 31.94万
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FY00549X%2F1
• 关键词: NSFDEB; NERC; Warming; silver; lining

The goal of our proposed research is to understand how long-term warming of stream ecosystems influences their response (i.e., resistance and resilience) to increasing prevalence and intensity of hydrologic drought. Anthropogenic greenhouse gas emissions from human activities are generating both a rise in global temperatures and an increase in the frequency and intensity of extreme climatic events. While shifts in these drivers are known to affect the structure and function of running waters separately, few studies have investigated their combined or interactive effects. The prevailing view is that warming and drought will combine to produce more extreme ecological consequences than would result from either stressor alone. Yet, emerging evidence suggests that warming may trigger 'compensatory' responses - both adaptive and ecological - that may have the potential to lessen the impacts of extreme drought. Our collaborative NSFDEB-NERC project will combine laboratory measurements (University of Iceland), stream mesocosm manipulations of temperature and drought (University of Birmingham, U.K.), and whole-reach drought manipulations (Hengill geothermal catchment, Iceland) to test the overarching hypothesis that long-warming enhances stream ecosystem stability (both resistance and resilience) in response to drought events. Our first objective is focused at the individual level, investigating whether physiological adaptations to warming influence invertebrate carbon use efficiencies and their role in drought resilience and recovery. Our second objective seeks to quantify resistance and resilience of entire invertebrate communities and their biomass production in response to drought across natural and experimental thermal gradients. Our final objective will explore the potential for ecosystem-level compensatory responses by examining how warming-induced shifts in nutrient supply and primary producers influence stability of ecosystem metabolism and nitrogen uptake in response to drought.

我们提出的研究的目标是了解河流生态系统的长期变暖如何影响其对水文干旱日益普遍和强度的反应（即抵抗力和恢复力）。人类活动造成的人为温室气体排放导致全球气温上升，极端气候事件的频率和强度增加。虽然已知这些驱动因素的变化会分别影响自来水的结构和功能，但很少有研究调查它们的组合或相互作用的影响。普遍的观点是，变暖和干旱结合起来会产生比单独任何一种压力因素更极端的生态后果。然而，新出现的证据表明，气候变暖可能会引发适应性和生态方面的“补偿”反应，这可能会减轻极端干旱的影响。我们的 NSFDEB-NERC 合作项目将结合实验室测量（冰岛大学）、流域温度和干旱的中宇宙操纵（英国伯明翰大学）和全范围干旱操纵（冰岛亨吉尔地热集水区）来测试总体假设：长期变暖增强了河流生态系统应对干旱事件的稳定性（抵抗力和复原力）。我们的第一个目标集中在个体层面，调查对变暖的生理适应是否影响无脊椎动物的碳利用效率及其在干旱恢复和恢复中的作用。我们的第二个目标旨在量化整个无脊椎动物群落的抵抗力和恢复力及其生物量生产，以应对自然和实验温度梯度的干旱。我们的最终目标将通过研究变暖引起的养分供应和初级生产者的变化如何影响生态系统代谢和氮吸收的稳定性来应对干旱，从而探索生态系统水平补偿反应的潜力。