Investigating marine carbon cycling using fatty acids and their stable carbon isotopes

使用脂肪酸及其稳定碳同位素研究海洋碳循环

• 批准号: 299311-2012
• 负责人: Budge, Suzanne
• 金额: $ 1.89万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=594932
• 关键词: Investigating; marine; carbon; cycling; using

The research interests of my group involve understanding lipid metabolism so that we can use lipids as a tool to trace carbon flow. Specifically, we are interested in the use of fatty acids (FA) in the study of carbon cycling and food web dynamics in the marine environment. FA are well suited to such studies because many dietary FA are incorporated into consumers with only minor modification to structure, making FA useful as indicators or biomarkers of their source. We propose to continue our ongoing work investigating the transfer of FA from prey to predators at low trophic levels, with the aim of developing a model to estimate predator diets. We will use two different types of information from FA data: 1) FA profiles. The proportions of FA in different species of prey are distinct and are passed to consumers with minor modification, allowing us to trace these FA signatures from prey to consumer fat stores; and 2) stable isotopes of specific FA. The distribution of carbon isotopes within specific FA of prey species are often different and are also passed to consumers with little change, allowing us to use stable isotopes of FA as an additional tracer. Both approaches, however, require investigation into the subtle biochemical changes that may occur in FA signatures or stable isotope ratios with digestion, deposition and mobilization in predator's fat stores. Thus, we propose to carry out a series of controlled feeding experiments using Atlantic pollock (Pollachius virens) as a model species to quantify any alterations in FA that may occur. With a clear understanding of biochemical changes, we can construct mathematical models to determine fish diets using FA information. These models can then be applied as part of a broader carbon-tracing technique that we are developing for application to the study of food web structure in a number of different environments. Specifically, we are interested in applying these models to ecosystems most susceptible to effects of climate changes, such as the Bering Sea and the northwest Atlantic, to detect changes in carbon cycling over time.

我小组的研究兴趣涉及了解脂质代谢，以便我们可以使用脂质作为追踪碳流量的工具。具体而言，我们对海洋环境中碳循环和食物网络动态的研究对使用脂肪酸（FA）感兴趣。 FA非常适合此类研究，因为许多饮食FA都将其纳入消费者中，仅适用于结构的修改，从而使FA作为其来源的指标或生物标志物有用。我们建议继续我们正在进行的工作，以调查FA从猎物到捕食者的转移，以低营养水平，以开发一个模型来估计捕食者饮食。我们将使用FA数据中使用两种不同类型的信息：1）FA配置文件。在不同种类的猎物中，FA的比例是不同的，并传递给了具有较小修改的消费者，从而使我们能够追踪这些FA签名，从猎物到消费者脂肪存储； 2）特定FA的稳定同位素。在猎物物种的特定FA中的碳同位素的分布通常不同，并且也传递给了消费者，而消费者几乎没有变化，从而使我们可以使用FA的稳定同位素作为额外的示踪剂。但是，两种方法都需要研究FA特征或稳定的同位素比的细微生化变化，并在捕食者的脂肪储存中进行消化，沉积和动员。因此，我们建议使用大西洋Pollock（Pollachius virens）作为模型物种进行一系列受控的喂养实验，以量化可能发生的FA中的任何变化。有了清楚地了解生化变化，我们可以使用FA信息构建数学模型来确定鱼类饮食。然后，这些模型可以作为一种更广泛的碳追溯技术的一部分，我们正在开发用于在许多不同环境中研究食品网络结构的应用。具体而言，我们有兴趣将这些模型应用于最容易受到气候变化影响的生态系统（例如白令海和西北大西洋）的影响，以检测随着时间的推移碳循环的变化。