Effects of altered precipitation regimes on wetland ecohydrology and biogeochemistry

降水模式改变对湿地生态水文学和生物地球化学的影响

• 批准号: 418197-2012
• 负责人: Duval, Timothy
• 金额: $ 2.26万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=551279
• 关键词: Effects; altered; precipitation; regimes; wetland

Wetlands are integral units in the landscape, providing a number of ecosystem services to society, including important hydrological, biogeochemical, ecological, and societal functions. Climate change scenarios are predicting decreased growing season precipitation concentrated in fewer, more intense extreme events in the Great Lakes region of North America. Hydrology is the single greatest control on wetland form and function. A shift in the distribution of precipitation may fundamentally alter wetland hydrological processes. Presently we have very little knowledge on the dynamics of wetland ecohydrology and biogeochemistry in response to individual precipitation events, and therefore we cannot accurately predict wetland response to changing precipitation regime. This research will address three objectives: 1) to investigate the response of near-surface wetland vertical hydrological and biogeochemical processes to changes in precipitation; 2) to understand the processes that lead to changes in wetland lateral flow and nutrient transfer dynamics in response to precipitation regimes; and, 3) to determine the resistance and resiliency of temperate wetland ecosystems to precipitation change through coupled plant-water-nutrient dynamics. It will use a combined field hydrometric and geochemical analysis approach with both lab and field experimentation on plant growth and rates of water movement and water source area. This research will provide clear ranges of wetland response and species threshold tolerances to precipitation-related climate change across wetland type in three geologic areas that land managers will utilize for more-informed strategic planning and projecting.

湿地是景观中不可分割的单元，为社会提供了许多生态系统服务，包括重要的水文、地球化学、生态和社会功能。气候变化情景预测，生长季降水量减少，集中在北美五大湖地区更少、更强烈的极端事件中。水文是对湿地形态和功能的最大控制。降水分布的变化可能从根本上改变湿地水文过程。目前，我们对湿地生态水文学和生态地球化学响应于单个降水事件的动力学知识很少，因此我们不能准确地预测湿地对变化的降水制度的响应。本研究的主要目的是：1）研究近地表湿地垂直水文和生态地球化学过程对降水变化的响应; 2）了解导致湿地侧向流和营养盐转移动态变化的过程对降水的响应;通过植物-水分-养分耦合动力学研究温带湿地生态系统对降水变化的抵抗力和恢复力。它将使用结合现场水文和地球化学分析方法，对植物生长和水运动速率以及水源区进行实验室和现场实验。这项研究将提供明确的湿地响应范围和物种阈值容忍度的降水相关的气候变化在三个地质区域的湿地类型，土地管理人员将利用更明智的战略规划和项目。