Dissolved organic matter dynamics in stream ecosystems

河流生态系统中溶解有机物的动态

• 批准号: RGPIN-2014-06526
• 负责人: Xenopoulos, Marguerite
• 金额: $ 1.97万
• 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: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=631926
• 关键词: Dissolved; organic; matter; dynamics; stream

One of the most obvious environmental changes caused by humans is the alteration of the landscape. Usuallythis involves the reduction of forested cover at the expense of agricultural and urban areas. Almost inevitably,these changes in land use affect the quality and quantity of surface and subsurface waters because of alteredconnections between the land and water. For rivers in these landscapes, new landscape connections can modifyorganic matter (generally measured in carbon units as dissolved organic carbon, DOC) which now originatesprimarily from agricultural crops, manure and urban waste instead of natural vegetation, soils and wetlands.Novel linkages with modified landscape and rivers also change the chemistry of river carbon, which canchange the healthy functioning of our rivers. In this project, I will examine how the DOC changes in qualityand quantity in river watersheds of contrasting land use from the Great Lakes Basin in South-central Ontario.These data will be used to further examine how land use alterations of physical (e.g., streamflow), chemical(e.g., nutrients), and biological (e.g., stream foodwebs) alter the processing and export of DOC. In doing so, Iwill test how agriculturally and urban-derived DOC and nutrients affects microbial growth, food webcomposition, and ecosystem function such as the decay of materials (leaf-litter), nutrient uptake by algae andnitrogen recycling. Finally, I will test for river DOC responses to climate change because these might beaffected by periods of warm weather and drought. This research will help us understand how human-derivedmaterials (agricultural fertilizers and residential waste) will affect the health and integrity of aquatic systems.

人类造成的最明显的环境变化之一是景观的改变。通常，这涉及以农业和城市地区为代价减少森林覆盖。几乎不可避免地，由于土地和水之间的变化，土地使用的这些变化会影响地表和地下水的质量和数量。 For rivers in these landscapes, new landscape connections can modifyorganic matter (generally measured in carbon units as dissolved organic carbon, DOC) which now originatesprimarily from agricultural crops, manure and urban waste instead of natural vegetation, soils and wetlands.Novel linkages with modified landscape and rivers also change the chemistry of river carbon, which canchange the healthy functioning of our rivers. In this project, I will examine how the DOC changes in qualityand quantity in river watersheds of contrasting land use from the Great Lakes Basin in South-central Ontario.These data will be used to further examine how land use alterations of physical (e.g., streamflow), chemical(e.g., nutrients), and biological (e.g., stream foodwebs) alter the processing and export of DOC.在此过程中，IWILL测试了农业和城市衍生的DOC和营养如何影响微生物生长，食物网络序列和生态系统功能，例如材料衰减（叶液），藻类和氮素回收利用的营养吸收。最后，我将测试河流对气候变化的反应，因为这些可能会因温暖的天气和干旱时期而产生。这项研究将有助于我们了解人类衍生品（农业肥料和住宅废物）如何影响水生系统的健康和完整性。