硬质海岸防护设施的生态效应与对策

虽然滨海地区占地球陆地面积不足4%，但沿海生境是全球最有价值的自然资源之一。世界上超过三分之一的人口生活在距海岸线100 km的范围内。气候变化和人类活动使得全球海岸侵蚀和风暴潮威胁加重。海岸防护可以有效抵御海岸侵蚀、风暴风险和海平面上升。本文概述了全球主要沿海国家和地区（欧盟、美国、中国）海岸硬化情况以及海岸硬化带来的生态效应。欧洲海岸线硬化比例为10%（2006年），美国海岸的硬化比例为14%（2015年），而中国海岸线的硬化比例近60%（2014年）。海岸硬化会引起滨海湿地重要物理、化学和生物过程的改变，生境丧失和破碎化，以及生物连通性的改变。增加硬化设施的结构复杂性或由混合型海岸代替传统硬化海岸可以减轻海岸硬化对滨海湿地生态系统的威胁，但对硬质海岸和混合型海岸的生态服务功能以及抵御风暴能力的评估还比较缺乏，有待进一步研究。

Ecological effect and countermeasures of hardening coastal defense

Although coastal areas account for less than 4% of the earth''s land area, coastal habitats are one of the world''s most valuable natural resources. Over one-third of the human population lives within 100 km of the coastline. Climate change and human activities exacerbate the global threat of coastal erosion and storm surges. Coastal protection is effective against coastal erosion, storm risk, and sea level rise. This paper summarized the coastal hardening conducted in major coastal regions of the world (EU, USA, and China) and the main ecological effects of coastal hardening. Ten percent of Europe''s coastline was hardened by 2006, approximately 14% of the total US coastline had been armored by 2015, and nearly 60% of China''s coastline was hardened by 2014. Shoreline hardening can lead to a series of changes in coastal wetlands, such as obstruction of important physical, chemical, and biological processes, habitat loss and fragmentation; and changes in biological connectivity. Increasing the structural complexity of hardening facilities and replacing traditional hardened defense with a hybrid coastal defense can reduce the threat of coastal hardening to coastal wetland ecosystems. However, the assessment of ecological service function and storm resistance of hardening defenses and hybrid coastal defenses is still lacking and needs to be further studied.