The Dynamics of Freshwater Food Webs Under Multiple Threats

世界各地的水生生态系统为人类提供关键的服务，包括淡水、食物资源和储存碳的能力，从而调节气候变化。了解淡水生态群落如何应对多种同步威胁，包括温度变化、农业径流、入侵物种和捕捞，对于维持这些服务的提供至关重要。这篇博士论文将重点放在来自温德米尔湖的一个独特的长期数据集，该数据集涉及超过项目广告的四个营养级别和50多个物种之间的物种相互作用。博士项目旨在应用现代统计建模和食物网建模方法，深入了解淡水生态系统对环境变化或缺乏环境变化的适应和抵抗机制。除了建模，PHD还将致力于填补低营养水平的关键数据空白，包括浮游植物和浮游动物功能组。具体地说，PHD的目标是1-解决浮游动物和浮游植物的功能组、分类学和体型大小，以帮助与核心生态学理论保持一致，将物种丰富的群落的身体大小、新陈代谢、生产和觅食与生物量动态联系起来。目标2-将现代统计模型(多变量自回归模型)应用于时间分辨的温德梅尔数据，重点关注营养级联、入侵物种的影响、气候变化和污染物。这一目标提供了一个超越谢菲尔德和CEH的合作，包括美国华盛顿大学的斯蒂芬妮·汉普顿博士，他是这些模型的专家。目标3-将已建立的跨5个营养级别的多营养多物种动力学模型参数化，以探索生态学理论是否可以预测实时序列中看到的对入侵物种、温度变化和污染物的响应类型。此外，还存在扩展工作以包括微生物群落和探索生态系统功能变化的机会。学生将加入一个活跃的研究小组，使用Julia和Rpring语言进行统计和数学建模，以回答有关生态系统的多种同时威胁对其提供的功能和服务的影响的主要问题。他们将成为谢菲尔德一个支持性和富有成效的实验室的一部分，并受益于与英国生态和水文中心建立的关系以及外部合作伙伴关系。培训和研究机会的结合为研究失调症内外的职业提供了一个极好的平台。

Aquatic ecosystems around the world provide criticalservices to humanity including freshwater, food resourcesand the capacity to store carbon and thus mediate climatechange. Understanding how freshwater ecologicalcommunities respond to multiple simultaneous threatsincluding temperature changes, runoff from agriculture,invasive species and harvesting is critical to maintain theprovision of these services.This PhD will focus on a unique long-term dataset fromLake Windermere on species interactions across more thanProject Advertisementfour trophic levels and among 50+ species. The PhDproject aims to apply modern statistical modelling and foodweb modelling methods to derive deep understanding ofthe mechanisms driving resilience and resistance toenvironmental change, or the lack thereof, in freshwaterecosystems. In addition to the modelling, the PhD will alsoaim to fill critical data gaps in lower trophic levels includingphytoplankton and zooplankton functional groups.Specifically, the objectives of the PhD areObj1 - resolve functional groups, taxonomy and body sizein zooplankton and phytoplankton to help align with coreecological theory linking body size, metabolism, productionand foraging to biomass dynamics of species richcommunities.Obj2 - Applying modern statistical models (MultivariateAutoregressive models) to the time resolved Windermeredata, with a focus on trophic cascades, invasive specieseffects, climate change, contaminants. This objective offersa collaboration beyond Sheffield and CEH, including Dr.Stephanie Hampton from University of Washington, USA,an expert in these models.Obj 3 - Parameterise an established multi-trophic multi-species dynamical model across 5 trophic levels to explorewhether ecological theory can predict the kinds ofresponses seen in real time series to invasive species,temperature change and contaminants.Additional opportunities exist to extend the work to includethe microbial community and to explore shifts inecosystem function.The student will join an active research group usingstatistical and mathematical modelling using Julia and Rprorgramming languages to answer major questions abouthow multiple simultaneous threats to ecosystems impact onthe functions and services they provide. They will be part ofa supportive and productive lab in Sheffield and benefitfrom established relationships with the UK Centre forEcology and Hydrology and external partnerships. Thiscombination of training and research opportunities providesan excellent platform for reserach careers in and out ofacademia.