Wetland Ecohydrological Sensitivity to Ground Ice Conditions

湿地生态水文对地面冰条件的敏感性

• 批准号: 261433-2012
• 负责人: Petrone, Richard
• 金额: $ 1.97万
• 依托单位: University of Waterloo
• 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=547761
• 关键词: Wetland; Ecohydrological; Sensitivity; Ground; Ice

Wetlands that dominate the Western Boreal Forest (WBF) are particularly important due to their capacity to store water and carbon. The Boreal zone spans the transition from persistent seasonal ground ice to discontinuous permafrost and is expected to experience unprecedented warming. This warming is likely to cause a hydrological-ecological response, particularly in wetlands. The region is also stressed by increased industrial activity that may exacerbate the effects of climatic variability on wetland sustainability. These disturbances lead to changes in ground ice conditions (including permafrost degradation at the northern extent of this region) and surface cover, which directly affect the tenuous balance between evapotranspiration and precipitation, thereby posing serious challenges for sustainable water and natural resource management. The strong influence of ground ice on wetlands in the Boreal zone likely makes these ecosystems particularly susceptible to "hot" positive feedbacks, where disturbance may cause rapid non-linear responses in local climate, hydrology and biota. However, there remains a lack of understanding of the rates of frost layer degradation and the effects on surface cover and hydrological-ecological processes. Since the spatial and temporal patterns of both seasonal thaws and permafrost thaw are governed by ground thaw energy, it is hypothesized that the processes and patterns of seasonal thaw can be studied as a surrogate for permafrost thaw. This will aid in our understanding of the trajectory of permafrost systems in response to climate and human disturbance. This research will examine how hydrological and ecological processes interact and differ among wetland systems over a range in ice conditions (seasonal ice, permafrost and degraded permafrost). To accomplish this, I will build on previous work in the plains region of the WBF and initiate detailed process work in the northern reaches of the region (Scotty Creek, NWT) where discontinuous permafrost is found. This will establish a unique transect of simultaneous process work that will address the above knowledge gap at a range of scales, and will be useful to scientists as well as policy makers and managers.

西部北方森林（WBF）中占主导地位的湿地因其储存水和碳的能力而特别重要。北方地带跨越了从持续的季节性地面冰到不连续的永久冻土的过渡，预计将经历前所未有的变暖。这种变暖可能会引起水文生态反应，特别是在湿地。该区域还受到工业活动增加的压力，这可能加剧气候多变性对湿地可持续性的影响。这些扰动导致地下冰状况（包括该区域北方地区的永久冻土退化）和地表覆盖发生变化，直接影响到蒸散量和降水量之间的脆弱平衡，从而对可持续的水和自然资源管理构成严重挑战。地面冰对北方带湿地的强烈影响可能使这些生态系统特别容易受到“热”正反馈的影响，在这种情况下，扰动可能会导致当地气候、水文和生物区系的快速非线性反应。 然而，人们对霜层退化的速度以及对地表覆盖和水文生态过程的影响仍然缺乏了解。由于季节性融化和冻土融化的空间和时间模式由地面解冻能量，它是假设的过程和模式的季节性融化可以研究作为一个替代冻土融化。这将有助于我们了解永久冻土系统对气候和人类干扰的反应轨迹。这项研究将研究在一定范围的冰条件（季节性冰、永久冻土和退化的永久冻土）下，湿地系统之间的水文和生态过程如何相互作用和差异。为了实现这一点，我将建立在以前的工作在平原地区的WBF和启动详细的过程工作在北方到达该地区（斯科特溪，西北地区），发现不连续的永久冻土。这将建立一个独特的断面同步过程工作，将解决上述知识差距在一系列的规模，并将是有用的科学家以及政策制定者和管理者。