Resilience and regime shifts in peatland microbial communities: implications for soil functioning

泥炭地微生物群落的恢复力和政权转变：对土壤功能的影响

基本信息

批准号：
NE/P013708/1
负责人：
Richard Bardgett
金额：
$ 32.1万
依托单位：
University of Manchester
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2017
资助国家：
英国
起止时间：
2017 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FP013708%2F1
关键词：
Resilience regime shifts peatland microbial

项目摘要

Humans rely on soils in many ways. They provide nutrients, water and anchorage for most of the crops that we eat, they filter and hold onto rainfall, and they store vast amounts of carbon, which helps to mitigate climate change. Soils also are home to a vast diversity of soil organisms, which play major roles in driving the biogeochemical cycles on which the functioning of Earth depends. Despite these important roles, a range of pressures, including changes in land management, land contamination, and climate change are threatening soils and the populations of microbes and animals that live in them. These pressures not only pose immediate threats to soil functioning, but also they could have longer-term impacts, for instance making soils more vulnerable to extreme climatic events, which are becoming more common worldwide as a result of climate change and can have devastating consequences for ecosystems. Evidence from studies of oceans, lakes and forests shows that extreme events, such as heat waves and drought, can trigger sudden and dramatic transitions, or regime shifts, from one ecosystem state to another. For example, reef communities off the western coast of Australia revealed a sudden and dramatic transition from extensive kelp forest to turf-forming seaweeds triggered by marine heatwaves. These regime shifts can have major consequences for the functions that these ecosystems provide. However, whether such regime shifts occur in soils is not really known. In this small grant, we would like to tackle three so far untested questions of high relevance for Soil Security. First, we want to know if long term climate warming makes soils and their microbial communities more vulnerable to, and less able to recover from, extreme climate events, namely drought, which is increasing in frequency. Second, we want to test if long-term effects of climate on soils and their microbial communities make them more vulnerable to transitions, or regime shifts from one state to another, and whether these regimes shifts degrade the functions that soils perform, for example their ability to store carbon. Last, we want to see if these effects of climate change on soil functioning can be dampened, for instance through changing the management of vegetation. We plan to make use of a unique warming and vegetation manipulation experiment that we set up several years ago on blanket peat at Moor House National Nature Reserve, northern England, funded by NERC. This experiment is ideally suited to this study because it has been running continuously since 2008, which puts us in a unique position to detect how long-term warming (9 years in 2017) has altered the resilience of soils and their microbial communities to drought, but also their susceptibility to regime shifts. The experiment also includes a vegetation manipulation treatment, which allows us to test if vegetation change, especially the presence of ericaceous dwarf-shrubs, can dampen effects of climate change on soils and their functioning. And finally, the experiment is on carbon-rich peatlands, which are not only of high relevance for UK Soil Security because they cover a large area of the UK land surface and store vast amounts of carbon, but also they add a distinct and highly complementary dimension to the NERC Soil Security Programme. These questions are at the heart of the NERC Soil Security programme which seeks to resolve what controls the ability of soils and their functions to resist, recover and ultimately adapt, to perturbations, such as those caused by extreme climatic events. Also, by testing our questions, we will gain new, transformative understanding of the dynamics of microbial communities and their functioning in relation to on-going and rapid environment change, and produce knowledge that could help in the design of sustainable management strategies for maintaining resilience in peatlands.

人类在许多方面都依靠土壤。它们为我们吃的大多数农作物提供营养，水和锚固，过滤并保持降雨，并存储大量的碳，这有助于减轻气候变化。土壤也是大量土壤生物的家园，它们在驱动地球功能所依赖的生物地球化学周期中起着重要作用。尽管这些重要作用，但包括土地管理，土地污染和气候变化的变化的压力正在威胁土壤以及生活在其中的微生物和动物的种群。这些压力不仅对土壤运作构成了立即威胁，而且可能会产生长期的影响，例如使土壤更容易受到极端气候事件的影响，由于气候变化，世界在全球范围内变得越来越普遍，并可能对此产生毁灭性的后果生态系统。对海洋，湖泊和森林的研究的证据表明，诸如热浪和干旱之类的极端事件可以触发突然和戏剧性的过渡，或者从一个生态系统状态到另一个生态系统到另一种生态系统状态。例如，澳大利亚西部海岸附近的礁社区揭示了从海洋热浪触发的广泛的海带森林到形成草皮的海藻的突然而戏剧性的过渡。这些政权转移可能会对这些生态系统提供的功能产生重大影响。但是，这种政权在土壤中是否发生这种状态的变化并不是真正的。在这笔小赠款中，我们想解决迄今为止三个未经测试的未经测试的问题，这些问题对土壤安全性有很高的相关性。首先，我们想知道长期的气候变暖是否会使土壤及其微生物群落更容易受到极端气候事件的攻击，也不太能够从频率增加的极端气候事件中恢复过来。其次，我们要测试气候对土壤及其微生物群落的长期影响是否使它们更容易受到过渡的影响，或者政权从一个州转移到另一种状态，以及这些政权是否会降低土壤所执行的功能，例如能够存储碳。最后，我们想看看气候变化对土壤功能的这些影响是否可以通过改变植被的管理来抑制。我们计划利用几年前在英格兰北部的Moor House National Natural Reserve，由NERC资助的Moor House National Natural Reserve的毯子泥炭上进行的独特变暖和植被操纵实验。该实验非常适合这项研究，因为它自2008年以来一直在不断运行，这使我们处于独特的位置，以检测长期变暖（2017年9年）改变了土壤及其微生物社区的韧性，干旱，干旱，干旱，而且他们对政权的敏感性也发生了变化。该实验还包括一种植被操纵治疗，使我们能够测试植被的变化，尤其是存在于矮矮的灌木丛的存在，可能会抑制气候变化对土壤及其功能的影响。最后，该实验是在富含碳的泥炭地上，不仅与英国的土壤安全相关，因为它们覆盖了英国的大片土地面积并储存了大量的碳，而且还增加了独特而高度互补的NERC土壤安全计划的维度。这些问题是NERC土壤安全计划的核心，该计划旨在解决如何控制土壤及其功能抵抗，恢复和最终适应扰动的能力，例如由极端气候事件引起的扰动。此外，通过测试我们的问题，我们将获得对微生物群落动态及其在持续和快速环境变化方面的功能的新变革性理解，并产生可以帮助设计可持续管理策略的知识来维持弹性在泥炭地。