Impacts of global warming in sentinel systems: from genes to ecosystems

全球变暖对哨兵系统的影响：从基因到生态系统

• 批准号: NE/M020886/1
• 负责人: Mark Trimmer
• 金额: $ 40.22万
• 依托单位: Queen Mary University of London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FM020886%2F1
• 关键词: Impacts; global; warming; sentinel; systems

The impacts of climate change, and warming in particular, on natural ecosystems remain poorly understood, and research to date has focused on individual species (e.g. range shifts of polar bears). Multispecies systems (food webs, ecosystems), however, can possess emergent properties that can only be understood using a system-level perspective. Within a given food web, the microbial world is the engine that drives key ecosystem processes, biogeochemical cycles (e.g. the carbon-cycle) and network properties, but has been hidden from view due to difficulties with identifying which microbes are present and what they are doing. The recent revolution in Next Generation Sequencing has removed this bottleneck and we can now open the microbial "black box" to characterise the metagenome ("who is there?") and metatranscriptome ("what are they doing?") of the community for the first time. These advances will allow us to address a key overarching question: should we expect a global response to global warming? There are bodies of theory that suggest this might be the case, including the "Metabolic Theory of Ecology" and the "Everything is Everywhere" hypothesis of global microbial biogeography, yet these ideas have yet to be tested rigorously at appropriate scales and in appropriate experimental contexts that allow us to identify patterns and causal relationships in real multispecies systems. We will assess the impacts of warming across multiple levels of biological organisation, from genes to food webs and whole ecosystems, using geothermally warmed freshwaters in 5 high-latitude regions (Svalbard, Iceland, Greenland, Alaska, Kamchatka), where warming is predicted to be especially rapid,. Our study will be the first to characterise the impacts of climate change on multispecies systems at such an unprecedented scale. Surveys of these "sentinel systems" will be complemented with modelling and experiments conducted in these field sites, as well as in 100s of large-scale "mesocosms" (artificial streams and ponds) in the field and 1,000s of "microcosms" of robotically-assembled microbial communities in the laboratory. Our novel genes-to-ecosystems approach will allow us to integrate measures of biodiversity and ecosystem functioning. For instance, we will quantify key functional genes as well as quantifying which genes are switched on (the "metatranscriptome") in addition to measuring ecosystem functioning (e.g. processes related to the carbon cycle). We will also measure the impacts of climate change on the complex networks of interacting species we find in nature - what Darwin called "the entangled bank" - because food webs and other types of networks can produce counterintuitive responses that cannot be predicted from studying species in isolation. One general objective is to assess the scope for "biodiversity insurance" and resilience of natural systems in the face of climate change. We will combine our intercontinental surveys with natural experiments, bioassays, manipulations and mathematical models to do this. For instance, we will characterise how temperature-mediated losses to biodiversity can compromise key functional attributes of the gene pool and of the ecosystem as a whole. There is an assumption in the academic literature and in policy that freshwater ecosystems are relatively resilient because the apparently huge scope for functional redundancy could allow for compensation for species loss in the face of climate change. However, this has not been quantified empirically in natural systems, and errors in estimating the magnitude of functional redundancy could have substantial environmental and economic repercussions. The research will address a set of key specific questions and hypotheses within our 5 themed Workpackages, of broad significance to both pure and applied ecology, and which also combine to provide a more holistic perspective than has ever been attempted previously.

气候变化的影响，尤其是变暖，对自然生态系统的理解仍然很差，迄今为止的研究集中在单个物种上（例如，北极熊的范围变化）。但是，多种植者系统（食物网，生态系统）可以具有新兴的特性，只能使用系统级别的观点才能理解。在给定的食物网络中，微生物世界是驱动关键生态系统过程，生物地球化学周期（例如碳循环）和网络属性的引擎，但由于难以识别存在哪些微生物以及他们在做什么，因此一直隐藏了视图。下一代测序的最近革命消除了这种瓶颈，现在我们可以打开微生物“黑匣子”来表征元基因组（“谁在那里？”）和metatranscriptome（“他们在做什么？”）第一次的社区。这些进步将使我们能够解决一个关键的总体问题：我们应该期望全球对全球变暖的反应吗？有一些理论的身体表明情况可能是这种情况，包括“生态学的代谢理论”以及“无处不在”的“无处不在”的假设，但尚未在适当的规模和适当的实验环境中严格测试这些思想，使我们能够识别真实的多层系统中的模式和因果关系。我们将使用在5个高纬度地区（Svalbard，Svalbard，Svalbard，Svalbard，Greenland，Alaska，Kamchatka）中使用地热变暖的淡水，从而评估从基因到食物网和整个生态系统的多个生物组织的变暖的影响，在这里预计温暖是特别快的。我们的研究将是第一个以这种前所未有的规模来表征气候变化对多种系统系统的影响的一项。这些“前哨系统”的调查将与在这些野外地点以及在实验室中机器人组合的微生物社区的1000秒的“人造溪流和池塘”中进行的建模和实验补充。我们新颖的基因到生态系统方法将使我们能够整合生物多样性和生态系统功能的度量。例如，除了测量生态系统功能（例如，与碳循环相关的过程）外，我们还将量化关键功能基因以及量化哪些基因（“ metatranscriptome”）。我们还将衡量气候变化对我们在自然界中发现的相互作用物种的复杂网络的影响 - 达尔文所谓的“纠缠银行” - 因为食物网和其他类型的网络可以产生违反直觉的反应，而这些反应无法通过孤立研究物种来预测。一个总体目标是评估面对气候变化时自然系统的“生物多样性保险”和弹性的范围。我们将将洲际调查与自然实验，生物测定，操纵和数学模型相结合。例如，我们将表征温度介导的生物多样性损失如何损害基因库的关键功能属性和整个生态系统的关键功能属性。学术文献和政策中有一个假设，即淡水生态系统相对有弹性，因为显然，功能冗余的范围可以使面对气候变化时可以赔偿物种损失。但是，这尚未在自然系统中进行经验量化，并且在估计功能冗余的大小时会产生实质性的环境和经济影响。这项研究将解决我们5个主题工作包中的一系列特定问题和假设，对纯净和应用生态学具有广泛意义，并且还结合起来，提供比以前尝试过的更全面的观点。