Coastal SEES Collaborative Research: Changes in actual and perceived coastal flood risks due to river management strategies

世界上人口最多的城市都坐落在三角洲沿岸洪泛平原上，因为那里土壤肥沃，自然资源丰富。由于人类活动引起的泥沙供应和河流流量的变化、陆地的逐渐下沉和海平面的上升，河流三角洲正在加速消失，威胁着沿海河流三角洲人类住区的可持续性。河流管理项目，包括那些旨在促进航运和减少洪水的项目，在某些情况下加速了土地流失，增加了飓风洪水的威胁。本项目将探讨人类河流管理、泥沙供应、湿地建设能力、沿海洪水风险和人类对洪水风险的感知之间的关系。测试河流管理、湿地损失和洪水风险之间的联系将改善对未来沿海系统状态的预测，并为如何可持续地管理沉积物供应和维持沿海地区的人类住区提供指导。其他更广泛的影响活动将包括研究生和本科教育、公共政策应用、公共和K-12外展。路易斯安那州（像许多其他三角洲海岸地区一样）普遍认识到，三角洲恢复科学对当地福利和经济有着强烈而直接的影响，这些都是统一的。该项目是美国国家科学基金会海岸科学、工程和教育可持续发展项目的一部分。该项目将探索三角洲景观和人类系统响应的共同演变，重点关注人类操纵沉积物输送导致的沿海洪水风险的变化。本文将对密西西比河三角洲平原中部三个具有不同河流输沙历史和湿地损失响应的沿海实验盆地进行研究。一个跨学科的研究团队将结合实地研究和建模方法来描述：1)人类河流管理策略之间的反馈，减少沉积物输送和相应的景观退化；2)减少沉积物输送导致的景观退化，飓风风暴潮导致的洪水风险增加，以及人类对洪水风险的反应之间的因果关系。该团队将探索河流管理策略的历史和未来成果，包括利用计算机模拟重组沿海地区的人类住区，并结合沉积物供应如何构建土地和人类对洪水风险的反应。在建模框架中测试这些系统的相互作用将产生基础知识，可以为管理决策提供信息，并促进三角洲景观上的可持续人类住区。

The most populated cities in the world are located on deltaic coastal floodplains because of their rich fertile soils and plentiful natural resources. River deltas are disappearing at increasing rates due to human-caused changes to sediment supply and river flow, gradual sinking of land, and rising sea level, threatening the sustainability of human settlements on coastal river deltas. River management projects, including those designed to promote navigation and reduce flooding, have in some cases accelerated land loss and increased the threat of hurricane flooding. This project will explore the relationships among human river management, sediment supply, wetland building capacity, coastal flood risk, and human perception of flood risk. Testing the connections between river management, wetland loss, and flood risks will improve prediction of future coastal system states and produce guidelines for how to sustainably manage sediment supply and maintain human settlement in coastal areas. Other broader impact activities will include graduate and undergraduate education, application to public policy, and public and K-12 outreach. These are all unified through the general recognition in Louisiana (like many other deltaic coasts) that the science of deltaic restoration has strong and direct impacts on local welfare and economies. This project is supported as part of the National Science Foundation's Coastal Science, Engineering, and Education for Sustainability program - Coastal SEES.This project will explore the co-evolution of deltaic landscapes and human system response by focusing on changes in coastal flood risks due to human manipulations of sediment delivery. Three experimental coastal basins in the central Mississippi River Deltaic Plain with distinct histories of sediment delivery by rivers and wetland loss responses will be investigated. An interdisciplinary team of researchers will combine field studies and modeling approaches to characterize: 1) feedbacks between human river management strategies that reduce sediment delivery and corresponding landscape degradation and 2) causal links between landscape degradation resulting from reduced sediment delivery, increased flood risks from hurricane storm surges, and human responses to perceived flood risks. The team will explore historical and future outcomes of river management strategies, including reorganization of human settlement in coastal areas using computer simulations incorporating how sediment supply builds land and human response to flood risks. Testing these system interactions in a modeling framework will produce foundational knowledge that can inform management decisions and promote sustainable human settlements on deltaic landscapes.