The role of algal-bacterial interactions in aquatic ecosystem function

藻类-细菌相互作用在水生生态系统功能中的作用

• 批准号: 371515-2009
• 负责人: Kirkwood, Andrea
• 金额: $ 1.75万
• 依托单位: University of Ontario Institute of Technology
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=483597
• 关键词: role; algal; bacterial; interactions; aquatic

Microbes are the essential drivers of biogeochemical cycling and carbon (energy)-flow in aquatic ecosystems. Within the context of ecosystem function, free-floating photosynthetic algae (phytoplankton) and heterotrophic bacteria (bacterioplankton) have distinct roles as primary producers and decomposers, respectively. Though often studied as autonomous functional-groups in aquatic ecosystems, algal and bacterial communities can interact in a variety of ways that are antagonistic and/or synergistic. To improve our understanding of energy flow and nutrient cycles across freshwater ecosystems, my research program will focus on the important roles of algae and bacteria as key players in aquatic ecosystem function and contaminant fate. Specifically, my research group will determine how the synergistic and antagonistic interactions between algae and bacteria mediate carbon, nutrient, and contaminant dynamics in lake systems. A series of small lakes from the "Land Between" ecotone in south-central Ontario will be the focus of our research program. The Land Between is a narrow ecological transition zone between limestone and granite-dominated bedrock along a transect from Parry Sound to Kingston in the Great Lakes Basin. The geological mosaic of the Land Between offers an ideal array of environmental gradients (i.e. pH, dissolved organic carbon, and nutrients) due to the variable physiography. As such, we will be able to directly assess the algal-bacterial communities in lakes representing a range of environmental characteristics, all within a relatively small geographic and climatic region. This research program will be the first of its kind to (1) Characterize the community structure/function of metabolically-distinct microbial groups in lakes, and (2) Show how algal-bacterial interactions influence carbon, nutrient, and contaminant dynamics in freshwater systems.

微生物是水生生态系统中生物地球化学循环和碳（能量）流动的基本驱动力。 在生态系统功能方面，自由漂浮的光合藻类（浮游植物）和异养细菌（浮游细菌）分别作为初级生产者和分解者发挥着不同的作用。 虽然藻类和细菌群落通常作为水生生态系统中的自治功能群进行研究，但它们可以以多种方式相互作用，这些方式是拮抗和/或协同的。 为了提高我们对淡水生态系统能量流动和营养循环的理解，我的研究计划将侧重于藻类和细菌作为水生生态系统功能和污染物命运的关键参与者的重要作用。 具体来说，我的研究小组将确定藻类和细菌之间的协同和拮抗作用如何介导湖泊系统中的碳，营养和污染物动态。 一系列来自安大略中南部“陆地之间”生态交错带的小湖泊将是我们研究计划的重点。 陆地之间是一个狭窄的生态过渡区之间的石灰岩和花岗岩为主的基岩沿着一个横断面从帕里湾金斯顿在五大湖盆地。 由于多变的自然地理，这片陆地的地质镶嵌图提供了一系列理想的环境梯度（即pH值、溶解有机碳和营养物质）。 因此，我们将能够直接评估代表一系列环境特征的湖泊中的藻类-细菌群落，所有这些都在相对较小的地理和气候区域内。 这项研究计划将是第一个（1）表征湖泊中代谢不同的微生物群体的群落结构/功能，以及（2）显示藻类-细菌相互作用如何影响淡水系统中的碳，营养和污染物动态。