Linking carbon to structure and function in aquatic ecosystems

将碳与水生生态系统的结构和功能联系起来

• 批准号: RGPIN-2019-04468
• 负责人: Xenopoulos, Marguerite
• 金额: $ 4.01万
• 依托单位: Trent University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=714897
• 关键词: Linking; carbon; structure; function; aquatic

Freshwater ecosystems are biogeochemical hotspots that play an important role in the global carbon cycle especially in relation to their relatively small geographic footprint. The rates at which lakes and rivers respire carbon (“metabolism”) is a key characteristic of these ecosystems. A central piece of the freshwater metabolism puzzle is dissolved organic matter (DOM), due to its very high prevalence and mobility across the landscape (from land to sea). DOM serves as a substrate for microbes, affects the light environment, and controls diverse food web and ecosystem processes in freshwater ecosystems. While DOM quantity has been recognized to be a central determinant of many lake and river properties, it is becoming increasingly clear that not all DOM is chemically equivalent and that its chemical composition (its quality) varies within and among aquatic ecosystems. In this project, I will examine how DOM quantity and quality is affected by nutrients and how, in turn, DOM quality and nutrients regulate ecological function in streams, rivers and lakes. Through a series of field surveys and experiments we will assess sources of DOM, determine pathways of DOM movement and loss, and understand patterns of DOM quality as they relate to nutrients in freshwater ecosystems through time and space. This information on the biogeochemical controls of carbon transformations and fluxes is integral to understanding the effects of global change and land use change on freshwater ecosystems across landscapes. My research team will include at least 15 highly diverse students that I will mentor to complete multidisciplinary research theses that can include principles of ecosystem ecology, water chemistry, biological activity, hydrological transport and mathematics. Finally, their research theses can provide information to management agencies on DOM, its interaction with nutrients, its retention in aquatic systems and its effects on ecological function with significant implications for ecosystem health and ecosystem services (e.g., recreation, drinking water, eutrophication).

淡水生态系统是生物地球化学热点，在全球碳周期中起着重要作用，尤其是与它们相对小的地理足迹有关。湖泊和河流呼吸碳（“代谢”）的速度是这些生态系统的关键特征。淡水代谢难题的中央部分是溶解的有机物（DOM），因为它在整个景观中的流行率很高（从陆地到海）。 DOM充当微生物的底物，影响光环境，并控制淡水生态系统中的潜水食品网和生态系统过程。尽管DOM数量已被认为是许多湖泊和河流特性的中心，但越来越清楚的是，并非所有DOM都是化学上等效的，并且其化学成分（其质量）在水生生态系统内部和之间也有所不同。在这个项目中，我将研究DOM数量和质量如何受养分的影响，而DOM质量和养分如何调节流，河流和湖泊中的生态功能。通过一系列的现场调查和实验，我们将评估DOM的来源，确定DOM运动和损失的途径，并了解DOM质量模式，因为它们与淡水生态系统中的养分相关，并通过时间和空间进行。有关碳转化和通量生物地球化学控制的信息是理解全球变化和土地利用变化对跨景观淡水生态系统的影响的重要组成部分。我的研究团队将包括至少15名高度多样化的学生，我将心态完成多学科研究，这些研究可能包括生态系统生态学，水化学，生物学活动，水文运输和数学的原理。最后，他们的研究论文可以向管理机构提供有关DOM的信息，其与养分的相互作用，其在水生系统中的保留以及对生态功能的影响，对生态系统健康和生态系统服务的影响（例如娱乐，饮用水，富营养化）具有重要意义。