Production, transport, fate and effects of lipids in the marine environment

海洋环境中脂质的产生、运输、归宿和影响

• 批准号: RGPIN-2017-04639
• 负责人: Parrish, Christopher
• 金额: $ 2.91万
• 依托单位: Memorial University of Newfoundland
• 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=711089
• 关键词: Production; transport; fate; effects; lipids

This study is all about taking it to the next level in marine food web research, both in terms of what we are probing and how we are doing it. We will see how lipids are transferred from one level of the food web to the next level up and we will use a new very sophisticated analytical approach to measuring entire suites of lipid compounds. Lipids are essential for life, providing energy, structure to cell membranes, and chemical messengers in organisms. Lipids are made biologically by processes under the influence of factors such as diet and temperature. Aquatic ecosystems occupy the largest part of the biosphere, and lipids in those systems provide the densest form of energy. Lipid dynamics can also strongly influence pollutant accumulation in marine food webs. Among the lipids, certain essential fatty acids such as long-chain omega-3 polyunsaturated fatty acids (PUFA), and sterols such as cholesterol are considered to be drivers of ecosystem health and stability. This study is a continuation of our ongoing program to investigate the importance of lipids in marine organisms and the cycling of these carbon-rich compounds in marine food webs. Objectives My long-term goal is to quantify production, transport, ultimate fate and effects of lipids in the marine environment, especially in the context of global change. Here my first objective is to compare lipid production, transport and fate in understudied cold and warm water ecosystems. With three of my current students and one new one we will examine four highly contrasted food webs: 1) The deep-sea food web located in the northwest Atlantic off Newfoundland, 2) Subarctic rhodolith beds off Newfoundland, 3) The subtropical euphausiid food web in the Gulf of California, and 4) The subtropical tuna food web in the southwest Pacific Ocean. My second objective is to examine the effect of changes in diet, temperature and acidity on the chemical composition of biological membranes with a new student, using new analytical technology. In tandem with my first objective, my third objective is to determine if there is an alternative biosynthetic pathway that is in operation in marine ecosystems for synthesizing critical PUFA. Knowing the origin of essential fatty acids present in deep and/or cold ecosystems is particularly important in the context of global change. Impact The characterization of energy flow in ecosystems is one of the main goals of ecology, and the analysis of how different levels of the food web interact is key to quantifying its flow. Lipids are central to these studies yielding more than twice the amount of energy per gram than proteins or carbohydrates, and providing essential fatty acids and phytosterols and cholesterol as well as a means to quantify the connections through detailed analysis of lipid compounds. Thus determination of the origin, abundance, and transfer of lipids will aid in effective monitoring of the sustainability and health of marine ecosystems.

这项研究将海洋食物网的研究提升到一个新的水平，无论是我们正在探索什么，还是我们是如何做的。我们将看到脂质是如何从食物网的一个层次转移到下一个层次的，我们将使用一种新的非常复杂的分析方法来测量整套脂质化合物。脂质是生命所必需的，为细胞膜提供能量，结构和生物体中的化学信使。脂质是在饮食和温度等因素的影响下通过生物过程产生的。 水生生态系统占据了生物圈的最大部分，这些系统中的脂质提供了能量的密集形式。脂质动力学也可强烈影响海洋食物网中污染物的积累。在脂质中，某些必需脂肪酸（如长链ω-3多不饱和脂肪酸（PUFA））和甾醇（如胆固醇）被认为是生态系统健康和稳定的驱动因素。这项研究是我们正在进行的项目的延续，该项目旨在调查脂质在海洋生物中的重要性以及这些富含碳的化合物在海洋食物网中的循环。 目标 我的长期目标是量化海洋环境中脂质的生产，运输，最终命运和影响，特别是在全球变化的背景下。 在这里，我的第一个目标是比较脂质的生产，运输和命运在未充分研究的冷水和温水生态系统。我现在的三个学生和一个新的，我们将研究四个高度对比的食物网：1）深海食物网位于西北大西洋纽芬兰岛，2）纽芬兰岛附近的亚北极rhodolith床，3）亚热带euphausiid食物网在加州湾，和4）亚热带金枪鱼食物网在西南太平洋。我的第二个目标是研究饮食，温度和酸度的变化对生物膜的化学成分的影响，与一个新的学生，使用新的分析技术。与我的第一个目标相一致，我的第三个目标是确定是否有一个替代的生物合成途径，在海洋生态系统中合成关键的PUFA。在全球变化的背景下，了解深层和/或寒冷生态系统中存在的必需脂肪酸的来源尤为重要。 影响 生态系统中能量流动的特征是生态学的主要目标之一，而分析不同层次的食物网如何相互作用是量化其流动的关键。脂质是这些研究的核心，每克产生的能量是蛋白质或碳水化合物的两倍多，并提供必需脂肪酸、植物甾醇和胆固醇，以及通过详细分析脂质化合物来量化连接的方法。因此，确定脂质的来源、丰度和转移将有助于有效监测海洋生态系统的可持续性和健康。