COLLABORATIVE RESEARCH: Spatial and Temporal Influences of Thermokarst Features on Surface Processes in Arctic Landscapes

合作研究：热岩溶特征对北极景观地表过程的时空影响

• 批准号: 0806329
• 负责人: Edward Rastetter
• 金额: $ 11.62万
• 依托单位: Marine Biological Laboratory
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0806329&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Spatial; Temporal; Influences

Recent summaries of international research clearly document the past and future extent of climate warming in the Arctic. These summaries suggest that in the future, rising temperatures will be accompanied by increased precipitation, mostly as rain: 20% more over the Arctic as a whole and up to 30% more in coastal areas during the winter and autumn. These climate changes will have important impacts on Arctic Systems. Of direct interest to this research is the likelihood that warming will promote permafrost degradation and thaw. Formerly frozen soils may be further destabilized by increased precipitation, leading to hillslope thermokarst failures. Recent work has documented that thermokarst failures are abundant and appear to have become more numerous around Toolik Lake on the eastern North Slope and in the western Noatak River basin in Alaska. A widespread and long-term increase in the incidence of thermokarst failures may have important impacts on the structure and function of arctic headwater landscapes. This research will use a systems approach to address hypotheses about how thermokarst failures influence the structure and function of the arctic landscape. It will focus on the composition of vegetation, the distribution and processing of soil nutrients, and exports of sediments and nutrients to stream and lake ecosystems. Results obtained at this hillslope scale will be linked to patterns observed at the landscape scale to test hypotheses about the spatial distribution of thermokarst failures in the arctic foothills. It is important to understand these interactions because perhaps the greatest potential impacts of changing land surface processes and formation of thermokarst failures are feedbacks to the climate system through energy, albedo, water, and trace gas exchange.This research is designed to quantify linkages among climatology, hillslope hydrology, geomorphology, geocryology, community ecology of vegetation, soil nutrient dynamics, microbial ecology, trace gas dynamics, and aquatic ecology. It will employ a combination of field experimentation, remote sensing, and simulation modeling as a means to quantify these relationships.

最近的国际研究总结清楚地记录了北极过去和未来气候变暖的程度。这些总结表明，未来，气温上升将伴随着降水量的增加，主要以降雨形式：冬季和秋季，整个北极地区的降水量将增加 20%，沿海地区的降水量将增加 30%。这些气候变化将对北极系统产生重要影响。这项研究的直接兴趣是变暖可能会促进永久冻土退化和融化。降水量增加可能会进一步破坏以前冻土的稳定性，导致山坡热喀斯特破坏。最近的工作记录了热岩溶破坏非常丰富，并且在北坡东部的图利克湖周围和阿拉斯加诺阿塔克河流域西部的热岩溶破坏似乎越来越多。热岩溶破坏发生率的广泛和长期增加可能对北极源头景观的结构和功能产生重要影响。这项研究将使用系统方法来解决有关热岩溶破坏如何影响北极景观的结构和功能的假设。它将重点关注植被的组成、土壤养分的分布和加工，以及沉积物和养分向河流和湖泊生态系统的输出。在该山坡尺度上获得的结果将与在景观尺度上观察到的模式联系起来，以检验有关北极山麓热喀斯特破坏空间分布的假设。了解这些相互作用非常重要，因为地表过程变化和热岩溶破坏形成的最大潜在影响可能是通过能量、反照率、水和微量气体交换对气候系统的反馈。本研究旨在量化气候学、山坡水文学、地貌学、地质冷冻学、植被群落生态学、土壤养分动态、微生物生态学、微量气体动态和水生环境之间的联系。 生态学。它将结合现场实验、遥感和模拟建模来量化这些关系。