Limnology and Biogeochemistry of Arctic Delta Lakes

北极三角洲湖泊的湖泊学和生物地球化学

• 批准号: RGPIN-2020-05478
• 负责人: Lesack, Lance
• 金额: $ 2.04万
• 依托单位: Simon Fraser 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=716586
• 关键词: Limnology; Biogeochemistry; Arctic; Delta; Lakes

Lakes associated with large river floodplains are among the most hydrologically complex, biologically productive, and biodiverse freshwater habitats in the world. They also face a wide range of threats and remain poorly understood because such systems represent vast areas of aquatic habitat world-wide, and global change is modifying the complex water level regimes that created these systems. The circumpolar Arctic coast is rich in such habitat, and is a region where climate is changing rapidly. The Mackenzie Delta is the second largest river floodplain in this region, and is one of the world's prominent aquatic ecosystems and a key ecosystem of the Canadian north because it functions as a biological hotspot relative to the surrounding arctic landscape. This delta is also on the leading edge of Arctic coastal changes because it is located in an area of subsidence that has enhanced relative sea level rise. It thus represents an exceptional model ecosystem to advance our fundamental understanding of aquatic habitat on large river floodplains. My long-term goal is to develop a general ecosystem paradigm for lakes on large river floodplains, not before possible, by teasing apart the varied mechanisms that create the combination of productivity, complexity, and diversity characteristic of these systems. This will advance our basic understanding of ecosystem complexity, and facilitate modeling of whether such systems respond resiliently or in surprising ways to multiple stresses of global change. Over the next 5 years, I will focus on advancing our understanding of how changing coastal Arctic water levels will affect: (1) the ability of methane cycling microbial communities to either release carbon in these waters to the atmosphere as greenhouse gases or convert the carbon to forms consumed by fish and other organisms; and (2) the ability of Arctic delta habitat to function as a biogeochemical hotspot that affects delivery of riverine nutrients to the ocean. Our work represents an exceptional opportunity for training highly qualified people in Arctic fieldwork and in fundamental research of broad interest in aquatic and Arctic sciences.

与大型河流洪泛区相关的湖泊是世界上最复杂，生物学生产性和生物多样性淡水栖息地之一。他们还面临着广泛的威胁，并且由于这些系统代表了全球范围内的广大水生栖息地，而且全球变化正在改变创造这些系统的复杂水位制度。圆形北极海岸富含这种栖息地，是气候迅速变化的地区。 Mackenzie Delta是该地区第二大河流洪泛区，它是世界上著名的水生生态系统之一，也是加拿大北部的关键生态系统，因为它是相对于周围北极环境的生物热点。该三角洲也处于北极沿海变化的前沿，因为它位于相对海平面上升的沉降区域。因此，它代表了一个非凡的模型生态系统，可以提高我们对大河流洪泛区水生栖息地的基本理解。我的长期目标是通过嘲笑各​​种机制，为这些系统的生产力，复杂性和多样性的特征结合起来，为大型河流洪泛区的湖泊开发一个一般的生态系统范式。这将提高我们对生态系统复杂性的基本理解，并促进对这种系统的反应或以令人惊讶的方式对全球变化的多种压力进行响应的建模。 在接下来的五年中，我将重点介绍我们对不断变化的沿海北极水位如何影响的理解：（1）甲烷循环微生物群落在这些水域中释放碳在大气中以温室气体或将碳转化为鱼类和其他生物体消耗的碳的能力； （2）北极三角洲栖息地充当生物地球化学热点的能力，影响了河流养分向海洋的递送。我们的工作代表了培训北极野外工作以及对水生科学和北极科学广泛兴趣的基本研究的培训高素质的机会的非凡机会。