Grassland parasites and community dynamics under climate change

气候变化下的草原寄生虫和群落动态

• 批准号: 2271808
• 金额: --
• 依托单位: Queen's University Belfast
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2271808
• 关键词: Grassland; parasites; community; dynamics; under

Global warming is affecting a wide range of organisms, including parasites of plants and animals. Most studies of the biological effects of climate change, however, consider physiological processes and single species responses, despite the fact that inter-species interactions are known to strongly influence outcomes of climate change at community level. This limitation could undermine predictions of future impacts of parasites on natural and agricultural ecosystems. This project will investigate how linked species in grassland-soil communities are affected by climate change, and how outcomes are influenced by interactions between species. This will enhance understanding of the effects of climate change on grazing system productivity and resilience. The project will focus on nematodes, which are major parasites of grazing livestock, and of grass itself. With rising anthelminthic resistance, the agricultural industry is looking towards more holistic strategies to alleviate infection pressure, and these will benefit from better understanding of the ecological context of parasite transmission.The specific aims of this project are to investigate how biotic interactions alter nematode parasite transmission in different grassland communities. This will be addressed using a combination of mesocosms, altered in situ environment experiments, and predictive modelling. Once key interactions have been determined, the project will investigate how they are affected under climate change. The impact of abiotic factors such as temperature and moisture will be considered in both their direct impacts, such as parasite thermal responses, and their indirect impacts through community interactions.The general approach will be to: (i) calibrate thermal response curves for key species in each functional group (including plant-parasitic and animal-parasitic nematodes, grass, and grazers); (ii) compare curves and identify 'winners and losers' under elevated temperature scenarios; and (iii) run dynamic models to compare outcomes under seasonally varying climates and climate change. Existing data on the climate-dependence of these groups will underpin model calibration and validation, complemented by additional experiments as needed. Following calibration, models will be tested and validated against longitudinal data on species responses under baseline and warmed field conditions. Work will be based primarily at Queen's University Belfast and CASE partners, the Agri-Food and Biosciences Institute (AFBI).Project results will enhance understanding of how the effects of different thermal responses among species in ecological communities are modified by the linkages between them to determine net impacts on ecosystem function. Outputs will illustrate how non-linear responses to climate change might affect natural and managed grassland systems. Model sensitivity analysis will map key species responses and vulnerabilities within the system, and support rational prioritisation of areas for future research. Scenario analysis will explore likely responses in terms of the stability and productivity of natural grassland systems, and rational adaptive management on livestock farms. Consequences of parasite adaptation to warming could also be explored through the model, and response curves compared among populations from different climatic zones.This project has potential benefits for the agricultural industry, by underpinning the design of more sustainable and resilient parasite control in grazing systems. Alleviation of reliance on chemical treatment of nematodes would slowing the development of resistance and hopefully provide alternative control options for farmers. This will benefit consumers, by helping to provide affordable food with decreased environmental impacts.

全球变暖正在影响广泛的生物体，包括植物和动物的寄生虫。然而，大多数关于气候变化的生物效应的研究都考虑了生理过程和单一物种的反应，尽管已知物种间的相互作用在社区层面上对气候变化的结果有很大的影响。这一限制可能会破坏对寄生虫对自然和农业生态系统未来影响的预测。该项目将调查草原-土壤群落中相互关联的物种如何受到气候变化的影响，以及物种之间的相互作用如何影响结果。这将加强对气候变化对放牧系统生产力和复原力影响的了解。该项目将重点放在线虫上，线虫是放牧牲畜和草本身的主要寄生虫。随着驱虫抗药性的提高，农业正在寻求更全面的策略来缓解感染压力，这将受益于更好地了解寄生虫传播的生态环境。该项目的具体目的是调查生物相互作用如何改变不同草原群落中线虫的传播。这将通过结合中胚层、改变的原地环境实验和预测模型来解决。一旦确定了关键的相互作用，该项目将调查它们在气候变化下是如何受到影响的。温度和水分等非生物因素的影响将在它们的直接影响(如寄生虫的热反应)和它们通过群落相互作用的间接影响两个方面得到考虑。一般方法将是：(I)校准每个功能组中关键物种(包括植物-寄生和动物-寄生线虫、草和食草动物)的热反应曲线；(Ii)比较曲线并确定高温情景下的“赢家和输家”；以及(Iii)运行动态模型，比较在季节性变化的气候和气候变化下的结果。关于这些群体气候依赖性的现有数据将支持模型校准和验证，并根据需要进行额外的实验。校准后，将对照基线和变暖野外条件下物种反应的纵向数据对模型进行测试和验证。工作将主要在贝尔法斯特女王大学和CASE合作伙伴农业-食品和生物科学研究所(AFBI)进行。项目成果将加强对生态社区物种之间不同温度反应的影响如何被它们之间的联系所改变的理解，以确定对生态系统功能的净影响。产出将说明对气候变化的非线性反应可能如何影响自然和管理的草原系统。模型敏感度分析将绘制系统内关键物种的反应和脆弱性，并支持合理确定未来研究领域的优先顺序。情景分析将探索在天然草地系统的稳定性和生产力以及畜牧场的合理适应性管理方面可能的反应。通过该模型还可以探索寄生虫适应气候变暖的后果，并比较来自不同气候带的种群之间的响应曲线。该项目通过支持在放牧系统中更可持续和更有弹性的寄生虫控制设计，对农业具有潜在的好处。减轻对线虫化学处理的依赖将减缓抗药性的发展，并有望为农民提供替代防治选择。这将有助于提供负担得起的食品，减少对环境的影响，从而使消费者受益。