Collaborative Research: Drainage network evolution following continental glaciation

合作研究：大陆冰川作用后的排水网络演化

• 批准号: 1656985
• 负责人: Peter Moore
• 金额: $ 12.32万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1656985&HistoricalAwards=false
• 关键词: Collaborative; Research; Drainage; network; evolution

When the Pleistocene ice sheets retreated from low-elevation continental interiors (for example, the upper Midwest), they left behind vast low-relief plains dotted with wetland basins and few well-established streams. It is evident from looking at landscapes formed on glaciated plains of different ages that elaborate stream networks become established over time, reducing the abundance and extent of wetlands and increasing the extent of streams. However, the rate and mechanism of this "drainage integration" is unknown. The consequences of drainage integration are significant not only because erosional reshaping modifies the physical landscape, but also because it forges faster and more direct hydrological connections between uplands and streams. These hydrological connections have important implications for water resource management throughout these landscapes.This collaborative project will combine laboratory simulations, computer modeling of landscape evolution, and field and geospatial analysis of stream network evolution in real Midwestern landscapes uncovered by Pleistocene ice sheets at different times in the last ice age. Each effort will be aimed at understanding the processes and rates of channel extension and wetland basin breaching in real and simulated landscapes. The key objectives are to identify how natural processes of water flow and sediment transport in these settings govern the spatial patterns of evolving stream networks and their rate of development through time.

当更新世的冰盖从低海拔的大陆内部（例如，上中西部）撤退时，它们留下了广阔的低地形平原，点缀着湿地盆地和很少的成熟河流。从不同年代的冰川平原上形成的景观可以明显看出，随着时间的推移，复杂的河流网络逐渐形成，减少了湿地的丰富程度和范围，增加了河流的范围。然而，这种“引流一体化”的速度和机制尚不得而知。流域整合的后果是显着的，不仅因为侵蚀重塑修改物理景观，而且因为它锻造更快，更直接的高地和溪流之间的水文连接。这些水文连接在这些landscapes.This合作项目将结合联合收割机实验室模拟，景观演变的计算机建模，并在真实的中西部景观揭示的更新世冰盖在最后一个冰河时代的不同时间的河流网络演变的现场和地理空间分析的水资源管理的重要影响。每一项工作的目的都是了解真实的和模拟景观中河道延伸和湿地流域破坏的过程和速率。主要目标是确定在这些环境中水流和泥沙输运的自然过程如何支配不断演变的河流网络的空间格局及其随时间的发展速度。