Empirical and Theoretical Integration of Geochemical and Morphologic Evolution of Soil-Covered Hillslopes: Responses to Channel Incision

土壤覆盖山坡地球化学和形态演化的经验和理论整合：对渠道切口的响应

• 批准号: 1132388
• 负责人: Kyungsoo Yoo
• 金额: $ 20.98万
• 依托单位: University of Minnesota-Twin Cities
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-30 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1132388&HistoricalAwards=false
• 关键词: Empirical; Theoretical; Integration; Geochemical; Morphologic; Empirical; Theoretical; Integration; Geochemical; Morphologic

River incision drives hillslope topography and this topography affects the chemical properties of the soil catena. However, the linkages between these two fundamental landscape properties as they evolve in response to basal channel incision, have not yet been quantitatively studied. This project integrates hillslope geomorphology based onsediment budgets with the spatial varioation in the geochemistry of soil. Modeling, field, and laboratory approaches are used to examine two key hypotheses. The first hypothesis states that at a given hillslope position, the rate of soil chemical weathering is limited by the rates of mineral supplies via soil transport and soil production. The second hypothesis states that the rate of soil chemical weathering is determined by the mean age and age distribution of minerals in the soil. Two independent models of hillslope soil mass balance and mineral grain tracking will be developed and combined with toposequence measurements of soil and bedrock elemental chemistry and soil production rates and Airborne Laser Swath Mapping. The study will be conducted at three hillslopes with increasing rates of basal channel incision within a tributary basin to the Feather River in the western Sierra Nevada, California. The outcomes from this study will include the temporal and spatial dynamics of soil chemical weathering rates within hillslopes experiencing different history and rates of basal channel incision rates. Landscapes are often characterized as repeating units of stream channels and hillslopes. This study will investigate the complex coupling between the formation of stream channels and soils. Both of these processes are relevant to managing land use effectively, maintianing sound agricultural practices, and evaluating how soils and landscapes change in response to a variety of natural and human-induced influences. The processes will be investigated in the field as well as in the laboratory and through the development of a sophisticated numerical model. The project will include science teachers in a local middle school and bring soil-stream interactions plus real-world scientific research into these classrooms.

河流切口驱动山坡的地形，该地形影响土壤Catena的化学特性。但是，尚未对这两种基本通道切口而演变的基本景观特性之间的联系，尚未进行定量研究。该项目将基于土地预算的山坡地貌与土壤地球化学的空间静脉曲张相结合。建模，现场和实验室方法用于检查两个关键的假设。第一个假设指出，在给定的山坡位置，土壤化学风化的速率受到通过土壤运输和土壤生产的矿物供应速率的限制。 第二个假设指出，土壤化学风化的速率取决于土壤中矿物质的平均年龄和年龄分布。 将开发两个独立的山坡土壤质量平衡和矿物谷物跟踪模型，并结合土壤和基岩元素化学和土壤生产速率以及空中激光swath映射的层状测量测量。这项研究将在三个山坡上进行，在加利福尼亚州内华达州西部的羽毛河支流盆地内的基础通道切口发生率增加。这项研究的结果将包括山坡内土壤化学风化速率的时间和空间动态，具有不同的历史和基础通道切口率的速度。景观通常被描述为溪流通道和山坡的重复单位。这项研究将研究溪流通道和土壤的形成之间的复杂耦合。这两个过程都与有效管理土地使用，维护声音农业实践以及评估土壤和景观如何变化，以应对各种自然和人类引起的影响。这些过程将在现场，实验室以及通过复杂的数值模型的开发中进行研究。该项目将包括当地中学的科学教师，并将土壤流相互作用以及对这些教室的现实科学研究带来。