多类型人类活动影响下河口沙坝-潟湖动力地貌系统的受损机制与恢复能力研究

High-intensity human activities have caused severe damage to the coastal environment in recent years. In response to this, the government is carrying out remediation projects in offshore areas such as "Blue Bay Project". However, the study on the scientific principles of remediation is still in its infancy. In particular, the understanding of damage mechanism and recovery capability of sand barrier-lagoon morphodynamic system at the estuary is still weak. This application takes the typical sand barrier-lagoon morphodynamic system at the Fudu estuary of Liaoning Province as the research object. Based on historical survey data and 20 years of long-term remote sensing imagery, combined with in-situ observations and numerical simulations, the coupling effects of various human activities on the damage of sand barrier-lagoon system is clarified. Furtherly, it reveals the self-adjustment and recovery capability of the sand barrier-lagoon morphodynamic system at the estuary. The implementation of different manual remediation measures is discussed to study the evolution and remediation effects of the sand barrier-lagoon system. This application aims to establish a quantitative evaluation system for recovery capability of the damaged sand barrier-lagoon morphodynamic system at the estuary, which breaks through existing partial subjective and qualitative evaluation models and achieves the best selection of artificial remediation measures. It can provide a scientific basis for the similar coastal remediation projects through this topic.

近年来，高强度人类活动对海岸环境造成严重破坏，国家针对性的开展“蓝色海湾”等整治工程，但关于整治修复科学原理的研究尚处于起步阶段，特别是对河口沙坝-潟湖动力地貌系统受损机制和恢复能力的认识还很薄弱。本申请以辽宁省浮渡河口典型沙坝-澙湖动力地貌系统为研究对象，基于历史调查资料和20年的遥感影像，结合现场调查和数值模拟，阐明多类型人类活动对河口沙坝-潟湖系统受损的耦合影响机制，揭示河口沙坝-澙湖系统的自我调整与恢复能力，探讨不同人工修复措施实施后河口沙坝-澙湖动力地貌演变规律和修复效果。本申请旨在构建河口沙坝-潟湖系统受损后恢复能力的定量评价体系，突破现有偏主观定性的评价模式，实现人工修复措施的最佳选择，可以为类似海岸整治修复工程提供科学依据。

沙坝-潟湖是典型的滨岸堆积地貌体，具有典型的生态系统和独特的景观、科研价值，近年来高强度的海岸开发和多种人类活动导致沙坝-潟湖发生剧烈演化，出现灭失和破坏，亟需研究和保护。本课题选取辽宁省浮渡河口沙坝-澙湖地貌系统，针对该研究区域存在河口筑坝、围填海和河道采砂等多种人类活动的特点，研究多类型人类活动对河口沙坝-渴湖系统的耦合影响，揭示人类活动下沙坝-潟湖海岸环境因子变化，分析沙坝-渴湖系统的受损机制并揭示其恢复能力，在此基础上给出人工修复建议。研究显示，沙坝-潟湖地貌系统正处于剧烈的演化过程中，SW向浪为主的波浪是沙坝向东延伸的主导动力条件，河流来沙减少是沙坝侵蚀的基础因素，海岸工程建设阻断了沿岸输沙路径，海岸工程的建设导致了局部海域潮流、波浪环境因子的剧烈改变。在人类干扰活动较小的阶段，SLHI会逐渐下降，即沙坝-潟湖地貌在经历剧烈的人为干预后会在海洋动力条件下逐步调整并渐趋动态平衡，海岸地貌得以自我恢复。本研究成果可以为沙坝-澙湖海岸的保护与恢复、原生海岸类型多样性保护等提供思路，为我国海岸整治修复工程提供可靠的理论指导和技术参考。