Quantifying the combined nutrient enrichment, pathogenic, and ecotoxicological impacts of livestock farming on UK rivers

量化畜牧业对英国河流的综合营养富集、致病和生态毒理学影响

• 批准号: NE/X016080/1
• 负责人: Penny Johnes
• 金额: $ 150.73万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX016080%2F1
• 关键词: Quantifying; combined; nutrient; enrichment; pathogenic

Livestock farming is the dominant farming type and source of organic matter pollution in UK freshwaters, with over 9.65M cattle and 32.7M sheep on 10M hectares of grassland, representing 57% of all agricultural land in the UK. When organic matter from livestock excreta is flushed to waters it drives changes in their physical, chemical and ecological quality and function. These include changes to the turbidity (and therefore light penetration), conductivity, benthic substrate character and oxygen regimes of the receiving waterbody, the delivery of agrochemicals including anti-microbial (antibacterial, antifungal, antiparasitic and antihelminth agents) and hormone compounds, both natural and derived from veterinary pharmaceutical use, all of which are likely to drive ecotoxicological impacts in receiving waters. They also contain nutrient-rich dissolved and particulate organic matter likely to drive eutrophication impacts in freshwater ecosystems, while also presenting a significant challenge for waters abstracted for human consumption. Pathogens, including bacteria and viruses, add to this portfolio of stressors, presenting a persistent problem for recreational water use, fisheries and shellfisheries in livestock farming areas. These stressors are likely to be present in most livestock excreta, but the extent to which different production systems and manure handling practices remove or reduce their concentration prior to their transfer to freshwaters is poorly understood. Nor do we understand the impact of the environmental character of the receiving waterbody on these ecotoxicological and nutrient enrichment impacts and pathogen persistence. Climate change-induced increases in water temperature and alterations in flow regime may then accelerate biological processing of this material, while the increased frequency of rainfall events predicted for the UK may overwhelm on-farm storage capacity, confounding efforts to reduce livestock impacts on freshwaters. There is thus an urgent need to understand interactions between these stressors, environment and management in driving changes in UK freshwater quality.QUANTUM will address this substantial knowledge gap, allowing us to better understand livestock farming as a key driver of changing UK quality in the livestock-dominated catchments of Wales, Scotland and Northern Ireland, and throughout the north and west of England. This new knowledge will help us create models that can better predict how UK freshwater quality functions in the presence of these multiple stressors, and how it is likely to change in future in response to climate change and mitigation efforts.We will achieve this by:1. Developing evidence on the composition of livestock excreta, how this varies according to manure handling and management, and their chemical and microbiological persistence in freshwaters, which will provide a new framework to define and contextualise pressures they exert on UK freshwaters.2. Exploring how different freshwater biota respond to this portfolio of stressors, allowing us to develop a predictive understanding of likely ecosystem responses to livestock management practices across the UK.3. Understanding how livestock excreta perturb the state of freshwater ecosystems, and how the multiple stressors in these fluxes interact with each other and environmental character, which is essential if we are to understand how these freshwater communities assemble, function and respond to changing livestock farming practices, under current, mitigated and climatically-altered conditions.4. Identifying the livestock production practices and management approaches likely to generate the lowest possible impacts on freshwater chemistry and ecosystems, which will provide critical underpinning for the developing policy and practice by our project partners, to minimise livestock farming impacts on UK freshwaters under ambient and changing climate.

畜牧业是英国淡水的主要农业类型和有机物污染的来源，在1000万公顷的草地上饲养着超过965万头牛和3270万只羊，占英国所有农业用地的57%。当牲畜排泄物中的有机物被冲入水中时，会导致其物理、化学和生态质量和功能发生变化。这些包括接收水体的浊度（以及因此的光穿透）、电导率、底栖底物特征和氧气状况的变化，农用化学品的输送，包括抗微生物（抗菌、抗真菌、抗寄生虫和抗蠕虫剂）和激素化合物（均为天然物质）以及源自兽医药物的使用，所有这些都可能对受纳水域产生生态毒理学影响。它们还含有营养丰富的溶解和颗粒有机物，可能会导致淡水生态系统的富营养化影响，同时也对人类消费的抽取水体提出重大挑战。包括细菌和病毒在内的病原体加剧了这一压力源，给畜牧业区的娱乐用水、渔业和贝类渔业带来了持续存在的问题。这些应激源可能存在于大多数牲畜排泄物中，但不同的生产系统和粪便处理方法在将其转移到淡水中之前消除或降低其浓度的程度尚不清楚。我们也不了解接收水体的环境特征对这些生态毒理学和营养富集影响以及病原体持久性的影响。气候变化引起的水温升高和水流状态的改变可能会加速这种材料的生物处理，而预计英国降雨事件频率的增加可能会压垮农场的储存能力，从而阻碍减少牲畜对淡水影响的努力。因此，迫切需要了解这些压力源、环境和管理之间的相互作用，以推动英国淡水质量的变化。QUANTUM 将解决这一巨大的知识差距，使我们能够更好地了解畜牧业是改变英国畜牧业质量的关键驱动因素- 统治威尔士、苏格兰和北爱尔兰以及整个英格兰北部和西部的流域。这些新知识将帮助我们创建模型，更好地预测英国淡水质量在这些多重压力因素存在下如何发挥作用，以及未来可能如何变化以应对气候变化和缓解努力。我们将通过以下方式实现这一目标：1 。开发关于牲畜排泄物成分的证据，这些成分如何根据粪便处理和管理而变化，以及它们在淡水中的化学和微生物持久性，这将提供一个新的框架来定义它们对英国淡水施加的压力并了解它们对英国淡水施加的压力。2。探索不同的淡水生物群如何应对这一系列压力源，使我们能够预测性地了解生态系统对英国牲畜管理实践可能做出的反应3。了解牲畜排泄物如何扰乱淡水生态系统的状态，以及这些通量中的多种压力源如何相互作用以及环境特征，如果我们要了解这些淡水群落如何组装、运作和应对不断变化的畜牧业实践，这一点至关重要，在当前、缓解和气候变化的条件下。4。确定可能对淡水化学和生态系统产生尽可能最低影响的畜牧生产实践和管理方法，这将为我们的项目合作伙伴制定政策和实践提供重要基础，以最大限度地减少畜牧业在环境和气候变化下对英国淡水的影响。