CAREER: Land Use, Geologic and Climatic Controls on Stream Processes in Northern New England Using Airborne Laser Swath Mapping

本计画整合遥感资料分析、野外调查与制图、以及河流模型，以检验北方新英格兰冰消景观中河流形态与过程的基本控制假说。晚更新世大陆冰川覆盖地区的河流是通过基岩侵蚀、推移质的可用性和运输以及生态演替的综合作用而演变的。河流形态，因此栖息地的适合性，在下游方向不同，这取决于当地的沉积源和汇。从森林砍伐到河岸保护的历史土地利用变化进一步影响了河流过程。目前，在缅因州大西洋鲑鱼几乎灭绝的激励下，非营利组织和政府机构正在努力通过稳定流域沉积物输入和拆除水坝来扭转河流栖息地的退化。然而，这些恢复工作通常是由其他地区鲑鱼河流的地貌研究指导的。该提案旨在了解土地利用变化对景观响应的轨迹，并开发和测试空间数值模型，将河流物理过程与栖息地质量联系起来。机载激光测绘（ALSM）将扩大过去15年来使用数字高程模型（DEM）在定量地貌学方面取得的进展。ALSM调查产生高分辨率的测量“裸土”地形，森林覆盖厚度，整个流域的水深。本研究将收集ALSM数据从三个流域在缅因州和使用通道形态测量作为输入的传输过程的数值模型。这些空间模型将通过与实地调查、地质和生态制图、鱼类种群数据集以及使用历史航空照片的过去条件进行比较来进行测试。本科生和硕士生团队将使用实地、地理空间和数值方法对每个流域进行研究。每个学生都将在团队中扮演一个角色，最终发展为研究项目的生产和演示。多年的学生参与将确保强大的教授学生，研究生本科生，本科生本科生指导。拟议的研究与北方新英格兰正在进行的生态系统恢复项目直接相关。这项研究的所有阶段都将包括学生和PI的直接外展，与土地管理人员，流域恢复非营利团体，高中生和来自各个领域的其他科学家在从实地研讨会到国家会议的论坛上分享结果和方法。这些努力将包括根据研究结果提出具体建议，以优化未来的恢复项目。通过与社区团体的互动，学生将获得对土地管理决策过程的挑战的赞赏。学生和利益相关者之间的这种交流将确保研究具有强大的社会和科学影响。

This project integrates analysis of remote-sensing data, field surveys and mapping, and fluvial models to test hypotheses of the fundamental controls on stream form and process in the deglaciated landscape of northern New England. Rivers in regions covered by late Pleistocene continental glaciers evolve through a combination of bedrock erosion, availability and transport of bedload, and ecological succession. Stream morphology, and therefore habitat suitability, varies in the downstream direction, depending on local sedimentary sources and sinks. Historical land-use change from deforestation to riparian protection further influences fluvial processes. At present, motivated by the near extirpation of Atlantic salmon in Maine, non-profit groups and government agencies are working to reverse fluvial habitat degradation by stabilizing watershed sediment inputs and removing dams. However, these restoration efforts are typically guided by geomorphic studies of salmon rivers in other regions. This proposal seeks to understand the trajectory of landscape response to changes in land use, and develop and test spatial numerical models that relate stream physical processes to habitat quality.Airborne laser swath mapping (ALSM) will expand the advances made in quantitative geomorphology using digital elevation models (DEMs) over the past 15 years. ALSM surveys yield high-resolution measurements of "bare-earth" topography, thickness of forest cover, and water depth over entire watersheds. This study will collect ALSM data from three watersheds in Maine and use channel morphologic measurements as input for numerical models of transport processes. These spatial models will be tested through comparison to field surveys, geological and ecological mapping, fish-population datasets, and past conditions using historical aerial photographs.Teams of undergraduate and Master's students will conduct the research, working together on each of the watersheds using field, geospatial, and numerical methods. Each student will have a role within the team that evolves to eventual production and presentation of research projects. Multi-year student involvement will ensure strong professor-student, graduate-undergraduate, and undergraduate-undergraduate mentoring. The proposed research is directly relevant to ongoing ecosystem restoration projects in northern New England. All phases of this study will include direct outreach by students and the PI to share results and methods with land managers, watershed restoration non-profit groups, high school students, and other scientists from a variety of fields in forums from field workshops to national meetings. These efforts will include specific recommendations, based on research findings, for optimizing future restoration projects. Through interactions with community-based groups, students will gain an appreciation for the challenges of land-management decision-making processes. This exchange between students and stakeholders will ensure that the research has a strong societal and scientific impact.