Collaborative Research: Investigation of Paleoenvironment, Geomorphic Processes, and Carbon Stocks of Drained Thaw-Lake Basins, Arctic Coastal Plain, Alaska

合作研究：阿拉斯加北极沿海平原排水解冻湖盆地的古环境、地貌过程和碳储量调查

• 批准号: 0240174
• 负责人: Wendy Eisner
• 金额: --
• 依托单位: University of Cincinnati Main Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2006-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0240174&HistoricalAwards=false
• 关键词: Collaborative; Research; Investigation; Paleoenvironment; Geomorphic

This is a collaborative proposal by Principal Investigators at the Universities of Wisconsin-Madison and Cincinnati. About 20% of the Arctic Coastal Plain is covered by thaw lakes developed over ice- rich permafrost and a larger proportion of this landscape is also scarred by drained thaw-lake basins, which become sites for the accumulation of organic carbon as peat deposits. The Principal Investigators will study of the origin of thaw-lake basins and associated geomorphological, biological, and pedological processes, building on work done on the Barrow Peninsula during 2000-2002. High-resolution multispectral satellite data will quantify the size frequency distribution and derive morphometric characteristics for lakes and drained thaw-lake basins across the Coastal Plain. In addition, drained lake basins will be selected for intensive ground-based analysis between Barrow and Atqasuk. The PIs will use the vegetation to select an equal number of young, medium, old and ancient drained thaw-lake basins. Ground-penetrating radar and extensive winter soil coring will be used to map unconformities between underlying lake sediments and the post-drainage organic deposit. Combined with satellite imagery to determine the areal dimensions, the volume of organics within the 40 basins will be estimated to determine the amount of soil carbon stored in the organic layer and upper lacustrine deposits. These results will estimate the amount of carbon sequestered in drained basins. Radiometric dating of the in situ peat above the clastic lake basin sediments will estimate of the date of lake drainage and basin inception. There is evidence to suggest that these events may be related to climatic change, while other lakes have drained in response to coastal erosion. The research will use paleoecological indicators to reconstruct the spatial and temporal response of vegetation and soil to climate on the Coastal Plain during the Holocene. High-frequency core dating will be used to derive carbon accumulation rates and organic soil chemistry and state of decomposition to determine whether carbon accumulation rates respond to regional changes in climate or if they are influenced to a greater degree by local rates of plant succession. Extensive spatial and temporal analysis of thaw-lake basins will 1) add to our understanding of the basic processes responsible for these important elements of the northern Alaskan landscape, 2) provide new information on landscape-scale response to climate change, and 3) help develop and validate causative models of environmental change and carbon sequestering. Broader impacts include 1) accessing traditional knowledge of local elders in Barrow, who have primary and secondary information on recent lake drainage and flooding events; 2) enhancing education of students at the Barrow High School through the recently established NASA-funded Alaskan Native Remote Sensing Education Project; 3) strengthening links with other U.S. agencies; and 4) continuing to provide scientific training to undergraduate students through several NSF programs. All satellite imagery, core stratigraphy, Global Positioning System transects, and pollen/microfossil data will be made publicly available through web sites, archives at the National Snow and Ice Data Center, and the Paleoenvironmental Arctic Sciences web site.

这是威斯康星大学麦迪逊分校和辛辛那提大学首席研究员的合作提案。 大约20%的北极沿海平原被富含冰的永久冻土层上形成的解冻湖所覆盖，而这一景观的很大一部分也被排干的解冻湖盆地所伤痕累累，这些盆地成为有机碳以泥炭沉积物的形式积累的场所。 首席研究员将在 2000 年至 2002 年期间在巴罗半岛所做的工作的基础上，研究解冻湖盆地的起源以及相关的地貌、生物和土壤过程。高分辨率多光谱卫星数据将量化沿海平原湖泊和排水融湖盆地的尺寸频率分布并得出形态特征。 此外，巴罗和阿特卡苏克之间还将选择干涸的湖盆进行深入的地面分析。 PI 将利用植被来选择同等数量的年轻、中期、古老和古老的排水融湖盆地。探地雷达和广泛的冬季土壤取芯将用于绘制下面的湖泊沉积物和排水后有机沉积物之间的不整合面。结合卫星图像确定面积尺寸，将估算 40 个盆地内的有机物体积，以确定有机层和上部湖沉积物中储存的土壤碳量。 这些结果将估算排水盆地中固存的碳量。 对碎屑湖盆沉积物上方的原位泥炭进行放射性测年将估计湖泊排水和盆地形成的日期。有证据表明这些事件可能与气候变化有关，而其他湖泊则因海岸侵蚀而干涸。 该研究将利用古生态指标来重建全新世期间沿海平原植被和土壤对气候的时空响应。高频核心测年将用于推导碳积累率以及有机土壤化学和分解状态，以确定碳积累率是否响应区域气候变化，或者是否在更大程度上受到当地植物演替率的影响。对融湖盆地进行广泛的空间和时间分析将1）增加我们对阿拉斯加北部景观这些重要元素的基本过程的理解，2）提供有关气候变化的景观规模响应的新信息，3）帮助开发和验证环境变化和碳固存的因果模型。 更广泛的影响包括 1) 获取巴罗当地长者的传统知识，他们拥有有关近期湖泊排水和洪水事件的一手和二手信息； 2) 通过最近成立的 NASA 资助的阿拉斯加原住民遥感教育项目，加强巴罗高中学生的教育； 3）加强与其他美国机构的联系； 4) 继续通过多个 NSF 项目为本科生提供科学培训。 所有卫星图像、核心地层、全球定位系统横断面和花粉/微化石数据将通过网站、国家冰雪数据中心档案以及古环境北极科学网站公开提供。