Establishing Regional Templates for Historic Reference Conditions for Lowland Riverine Landscapes: Seeing Through Human-Related Homogenization in the Puget Lowland

大型洪泛平原河流的景观是最复杂和最具生物生产力的河流之一，其生态系统受到的威胁最为严重。这些洪泛平原是重要的自然资源，因此是人类最密集利用和广泛改造的景观之一。更好地了解这些环境将有助于恢复这些洪泛平原，有效地管理土地和河流的利用，但人们对温带地区的这些河流知之甚少，这主要是因为历史上与人类有关的变化的简化、均质化和模糊的影响。该研究项目将调查华盛顿州普吉特低地地区的河流景观，将其作为物理、生态和人类系统的耦合。研究者将开发多尺度、空间明确的景观演变和过程模型，通过调查地貌模板的地质演化的空间（100公里至1米以内）和时间（10,000年至不到一年）控制，以及模板如何构造河流生态系统。他还将研究和开发重建人类相关变化时期之前的生物物理景观条件的方法。该项目将采用多种交叉参考方法，包括档案、实地和地形（高分辨率数字高程模型）代理和现有的自然代理研究。这些方法将整合为三个研究组成部分：理解全新世景观演化；河流过程和动力学研究；和GIS制图的预定居景观。研究人员将处理几个问题的假设，包括更新世冰川的遗产对同一地理省份的现代河流剖面施加了不同的不平衡条件；形成现代河流形态和动态对比的不平衡条件；其他物理过程，如全新世火山泥流和全新世同震隆升和沉降，如何在特征时空尺度上改变这个模板，但没有从根本上改变它；以及自然景观演变如何导致在河谷尺度上定义的景观过程域，并在地理省内可预测地形成格局。他还将讨论地球物理模板强烈影响生态系统组装的假设。特别是，他将研究大型河岸树木在某些领域的存在是否催化了多种生物地貌反馈机制，这些机制定义了生态系统走向自我强化状态的轨迹，从而组织和维持河流过程和地貌以及森林河谷生态系统的结构和功能。该项目将提供地理信息系统产品和支持在线地理空间数据，创建互联网地图服务器（IMS），以及区域河流景观及其随时间变化的在线地图集。该项目将研究低地河流景观的演变、历史和功能。它将为低地河流景观的物理演化、时空尺度和构成这些景观的关键过程以及物理过程与生态系统之间的动态关系提供基础景观科学的见解。它将为理解多尺度的河流景观和重建其定居前的生物物理条件提供方法。这些见解和方法在管理、恢复、土地和河流利用规划中有着广泛的应用。该项目还将为研究人员、机构、非政府组织和公民团体创建在线资源，并为其他地区的此类在线资源模式做出贡献。

The landscapes of large floodplain rivers are among the most complex and biologically productive, and their ecosystems are among the most critically threatened. These floodplains are important natural resources and therefore are among the landscapes most intensively used and extensively modified by humans. Efforts to restore these floodplains and manage land and river uses effectively will benefit from better understanding these environments, but such rivers in the temperate-zone are poorly understood, largely because of the simplifying, homogenizing, and obscuring effects of historical human-related change. This research project will investigate river landscapes in the Puget Lowland region of the state of Washington as coupled physical, ecological, and human systems. The investigator will develop multi-scale, spatially explicit landscape evolution and process models by investigating the spatial (100 km to less than 1 m) and temporal (10,000 years to less than one year) controls on geological evolution of the geomorphic template as well as how the template structures riverine ecosystems. He also will investigate and develop methods to reconstruct biophysical landscape conditions prior to periods of human-related change. The project will employ multiple, cross-referencing approaches, including archival, field, and topographic (high-resolution digital elevation model) proxies and existing natural proxy studies. These approaches will be integrated into three study components: understanding Holocene landscape evolution; riverine process and dynamics studies; and GIS mapping of the pre-settlement landscape. The researcher will address hypotheses that deal with several issues, including the legacy of Pleistocene glaciation imposes contrasting disequilibrium conditions onto modern river profiles in the same physiographic province; the disequilibrium conditions that force contrasting modern river morphologies and dynamics; how other physical processes, such as Holocene lahars and Holocene co-seismic uplift and subsidence, operating at characteristic temporal and spatial scales modify this template but do not fundamentally change it; and how physical landscape evolution results in landscape process domains defined at a river valley scale and are predictably patterned within the physiographic province. He also will address the hypothesis that the geophysical template strongly influences ecosystem assembly. In particular, he will examine whether the presence of large riparian trees in certain domains catalyzes multiple biogeomorphic feedback mechanisms that define an ecosystem trajectory toward a self-reinforcing state, thereby organizing and maintaining fluvial processes and landforms and the structure and function of forested river valley ecosystems. The project will provide GIS products and supporting geospatial data online, create an Internet Map Server (IMS), and an online atlas of the regional riverine landscape and its change through time.This project will investigate the evolution, history, and function of lowland river landscapes. It will provide insights to basic landscape sciences on the physical evolution of lowland riverine landscape, the time and space scales and critical processes that structure these landscapes, and the dynamics between physical processes and ecosystems. It will provide methodologies for understanding riverine landscapes at multiple scales and for reconstructing their pre-settlement biophysical condition. These insights and methodologies have broad application in management, restoration, and land and river use planning. The project also will create online resources for researchers, agencies, NGOs, and citizen groups and contribute toward a model for such an online resource for other regions.