Biodiversity and the water cycle: can rewilding mitigate the impacts of hydrological extremes?

生物多样性和水循环：野化能否减轻极端水文的影响？

• 批准号: NE/W007460/1
• 负责人: Gemma Louise Harvey
• 金额: $ 5.1万
• 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: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW007460%2F1
• 关键词: Biodiversity; water; cycle; rewilding; mitigate

Managing and responding to floods and droughts in the UK demands vast amounts of public spending, and the frequency and severity of extreme high and low flows will increase under future climate change. Many parts of our river catchments have been heavily modified over long timescales, but there is now increasing evidence that working with natural ecosystem processes can deliver multiple environmental, social and economic benefits. The rewilding of degraded landscapes is increasing in popularity globally, and represents a vital tool in reversing biodiversity decline. The changes in biodiversity arising from rewilding also have the potential to drive wider benefits, but many of these remain largely unexplored.Rewilding is the practice of returning modified landscapes to a wilder state and may include the reintroduction of missing animal species. Approaches to rewilding are wide-ranging, but the types of biodiversity change include natural regeneration of grassland, woodland and scrubland, increased biodiversity of soil-dwelling organisms, and reintroduction of large herbivores (e.g. cattle, deer, pigs) and keystone species that have disproportionately large effects on ecosystems relative to their population size (e.g. beavers, wolves). Many of the animals and plants that recolonise rewilding projects are effective 'ecosystem engineers': organisms that are capable of modifying habitats and flows of resources in ecosystems. The presence of ecosystem engineers has been linked with increased success of environmental restoration projects.Importantly, the fundamental principles that underpin rewilding offer potential for much wider-ranging benefits to support freshwater and terrestrial natural capital assets and ecosystem services but understanding of these wider effects is limited. A key knowledge gap is understanding the capacity for rewilded landscapes to modify the water cycle and mitigate hydrological extremes. This would contribute to the evidence base for the economics of biodiversity by delivering more effective water resource and water hazard management. Rewilding, by nature and scale, will alter key elements of the water cycle. Changes to soils, vegetation and river-floodplain systems arising from rewilding will alter the movement and storage of water within landscapes. If rewilding outcomes mean that water takes slower routes through the landscape, it has the potential to make important contributions to flood and drought mitigation. Our project will explore the role that biodiversity gains from landscape rewilding play in modifying the water cycle and mitigating the impacts of hydrological extremes. We will use a review of the existing evidence from rewilding projects, other forms of landscape restoration and sustainable land management, and semi-natural ecosystems, to assess the state of the evidence for key types of rewilding-driven biodiversity change, and identify knowledge gaps and future priorities. In particular, we will answer the questions: 1. How does rewilding alter hydrological processes? 2. How do these effects differ across rewilding scenarios and environmental settings? 3. To what extent have these changes delivered measurable effects on floods and low flows? 4. Where are the gaps in knowledge across questions 1 to 3?Answering these questions will determine the ways in which rewilding influences hydrology and hydrological extremes, support decision-making in rewilding practice across public and private sectors and inform future research priorities and improved monitoring of rewilding programmes.

管理和应对英国的洪水和干旱需要大量的公共支出，在未来的气候变化下，极端高流量和低流量的频率和严重程度将增加。我们河流流域的许多部分在很长一段时间内都发生了重大变化，但现在越来越多的证据表明，利用自然生态系统过程可以带来多种环境，社会和经济效益。在全球范围内，退化景观的重新野生化越来越受欢迎，是扭转生物多样性下降的一个重要工具。野化引起的生物多样性变化也有可能带来更广泛的利益，但其中许多利益在很大程度上尚未得到探索。野化是将经过改造的景观恢复到更怀尔德状态的做法，可能包括重新引入失踪的动物物种。野化的方法多种多样，但生物多样性变化的类型包括草地、林地和灌木丛的自然再生，土壤生物的生物多样性增加，以及重新引入大型食草动物（如牛、鹿、猪）和相对于其种群规模对生态系统产生不成比例的巨大影响的关键物种（如海狸、狼）。许多支持野化项目的动物和植物都是有效的“生态系统工程师”：能够改变生态系统中栖息地和资源流动的生物。生态系统工程师的存在与环境恢复项目的成功率提高有关。重要的是，支持恢复野生化的基本原则提供了支持淡水和陆地自然资本资产和生态系统服务的更广泛利益的潜力，但对这些更广泛的影响的理解有限。一个关键的知识差距是理解野生景观改变水循环和缓解水文极端情况的能力。这将通过提供更有效的水资源和水灾害管理，为生物多样性经济学提供证据基础。自然和规模的野化将改变水循环的关键要素。由于重新野化而引起的土壤、植被和河流-洪泛平原系统的变化将改变景观内水的流动和储存。如果野化的结果意味着水在景观中的速度较慢，那么它有可能为减轻洪水和干旱做出重要贡献。我们的项目将探讨生物多样性从景观改造中获得的作用，在改变水循环和减轻水文极端的影响。我们将利用现有的证据从野化项目，其他形式的景观恢复和可持续土地管理，半自然生态系统的审查，评估的关键类型的野化驱动的生物多样性变化的证据的状态，并确定知识差距和未来的优先事项。特别是，我们将回答以下问题：1。野化如何改变水文过程？2.这些影响在野化情景和环境设置中有何不同？3.这些变化在多大程度上对洪水和低流量产生了可衡量的影响？4.问题1至3的知识差距在哪里？探讨这些问题将确定野化影响水文和水文极端情况的方式，支持公共和私营部门野化实践的决策，并为未来的研究重点和改进野化方案的监测提供信息。

项目成果

The role of rewilding in mitigating hydrological extremes: State of the evidence

• DOI: 10.1002/wat2.1710
• 期刊: Wiley Interdisciplinary Reviews: Water
• 作者: Gemma L. Harvey;Adam T. Hartley;A. Henshaw;Zareena Khan;Stewart J. Clarke;Christopher J. Sandom;Judy England;Sara King;Orlando Venn

Rewilding and the water cycle

野化和水循环

• DOI: 10.1002/wat2.1686
• 发表时间: 2023
• 期刊: WIREs Water
• 影响因子: 8.2
• 作者: Harvey G