Stuck in the mud: addressing the fine sediment conundrum with multiscale and interdisciplinary approaches to support global freshwater biodiversity

陷入困境：采用多尺度和跨学科方法解决细小沉积物难题，支持全球淡水生物多样性

• 批准号: MR/Y020200/1
• 负责人: Kate Mathers
• 金额: $ 75.02万
• 依托单位: Loughborough University
• 依托单位国家: 英国
• 项目类别: Fellowship
• 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=MR%2FY020200%2F1
• 关键词: Stuck; mud; addressing; fine; sediment

Environmental change is happening on a global scale. Freshwater ecosystems represent some of the most endangered habitats in the world, with declines in diversity (83% in the period 1970-2014) far exceeding that of terrestrial counterparts. One of the primary causes of reduced riverine ecosystem health is a loss of habitat associated with excessive fine sediment deposition (typically referred to as particles <2mm). Fine sediment is a natural part of river systems, however alterations to land use (e.g. intensive farming) and channelization / impoundment (via dams and reservoirs) have altered the quantity of fine sediment such that inputs now far exceed historic levels. Additionally, increasing hydrological extremes associated with climatic change, such as intense rainfall events, are likely to further increase the delivery of fine sediment to river channels.Fine sediment deposition alters and degrades instream habitats making rivers unsuitable for flora and fauna to live in. Such changes lead to reductions in the biodiversity of riverine ecosystems and affects all components of the food web from fish and insects through to algae. Understanding the ecological implications of fine sediment is therefore imperative to be able to manage our rivers so that they can support and sustain healthy ecosystem functioning and support anthropogenic activities (e.g., fisheries, recreational activities). This is however challenging because a number of environmental factors control the consequences of fine sediment for flora and fauna. The proposed Fellowship aims to understand and quantify which environmental factors (e.g. land use, size of fine sediment and of the gravels within the river, time of year) influence the severity of fine sediment deposition for rivercommunities. Specific objectives are to (i) quantify the trends between fine sediment loading and ecological responses in the UK and internationally; (ii) determine if there is a threshold of fine sediment loading before ecological degradation occurs and how this varies within individual rivers, (iii) develop understanding of how environmental controls (e.g. grain size, hydrological exchange) structure the effects of fine sediment and; (iv) outline a future research agenda to tackle the management of fine sediment in rivers. In achieving these objectives, my Fellowship will provide a framework to determine when and which river types (e.g. highland or lowland, geology) are most at threat from fine sediment pressures internationally. The Fellowship will focus on macroinvertebrates (river invertebrates such as snails, insects and crustaceans) as a target organisms being abundant, diverse and occurring across the globe. The Fellowship represents a novel and exciting research programme with international reach and applicability that combines global datasets with multi-country field and artificial stream channel experiments (alpine and lowland) and laboratory experiments over different spatial scales to develop and validate theories spanning different environmental settings. The fellowship will lead to an exciting step-change in our understanding and will address unique fundamental research questions whilst working synergistically with UK statutory regulatory agencies and end-users such as the Environment Agency of England, Natural Resources Wales and Scottish Environmental Protection Agency. The research generated will have important ramifications for how stakeholders allocate resources to monitor and manage UK riverine ecosystems and will enable more efficient and targeted conservation and restoration plans.

环境变化正在全球范围内发生。淡水生态系统代表了世界上一些最濒危的栖息地，多样性下降（1970-2014时期的83％）远远超过了陆地对应物的栖息地。河流生态系统健康降低的主要原因之一是与过度细沉积物沉积相关的栖息地丧失（通常称为颗粒<2mm）。精细沉积物是河流系统的自然部分，但是土地使用的变化（例如，强化农业）和通道化 /蓄水池（通过大坝和水库）改变了细泥沙的数量，以至于输入现在远远超过了历史水平。此外，与气候变化相关的越来越多的水文极端发生，例如强烈的降雨事件，可能会进一步增加对河道的良好沉积物的传递。-炎性沉积物的沉积变化并降低了乐器栖息地，使河流不适合植物和动物群生活。这种变化会导致河流生态学的生物多样性造成的生物多样性，从而使远处的昆虫和昆虫的食物以及各种昆虫的成分都伴随着各种成分。因此，必须能够管理我们的河流，以便他们可以支持和维持健康的生态系统功能并支持人为活动（例如渔业，娱乐活动），因此必须了解精细沉积物的生态含义。然而，这是具有挑战性的，因为许多环境因素控制着精细沉积物对动植物的后果。拟议的奖学金旨在了解和量化哪些环境因素（例如，土地利用，细小的沉积物和河流内的砾石的大小，一年中的时间）影响了河流社区的精细沉积物沉积的严重性。具体的目标是（i）量化英国和国际上的精细沉积物负荷与生态反应之间的趋势； （ii）确定在生态降解发生之前是否存在精细沉积物的阈值，以及在单个河流中的变化，（iii）对环境控制（例如晶粒尺寸，水文交换）结构的理解，结构细沉积物的影响； （iv）概述了未来的研究议程，以解决河流中精美沉积物的管理。在实现这些目标时，我的奖学金将提供一个框架，以确定何时以及哪种河流类型（例如高地或低地，地质）在国际上受到高级沉积压力的威胁。该研究金将集中在大型无脊椎动物（蜗牛，昆虫和甲壳类动物等河流无脊椎动物）上，因为目标生物丰富，多样化，并且发生在全球范围内。奖学金代表了一项具有国际覆盖范围和适用性的新颖而令人兴奋的研究计划，将全球数据集与多国领域和人工流渠道实验（Alpine和Lowland）结合在一起，以及在不同空间尺度上进行的实验室实验，以开发和验证跨越不同环境环境的理论。奖学金将导致我们的理解中令人兴奋的步骤变化，并将解决独特的基本研究问题，同时与英国法定监管机构和最终用户协同工作，例如英格兰环境局，自然资源威尔士和苏格兰环境保护局。所产生的研究将对利益相关者如何分配资源来监视和管理英国河流生态系统，并将实现更高效，有针对性的保护和恢复计划，对此产生重要的影响。