Coastal wetland ecosystems are among the most productive yet highly threatened systems in the world.Being typical ecologically vulnerable zones,coastal wetland ecosystems are not only the most active area on earth's surface and are affected by anthropogenic activities.Therefore,the severity of anthropogenic pressure on the environment is increasing.In recent decades,the reclamation of coastal wetland for agricultural and architectural land use has been a common practice worldwide.It has become an important method of meeting the increasing demand of space for living and development in China.This paper summarized the history and status quo of coastal reclamation briefly,analyzed the effects of reclamation activity on coastal eco-environment from the aspects of soil properties,biodiversity,land use and landscape pattern,ecological security,and ecosystem services.The present study showed that with the increase in time after reclamation,1) tidal fiat soil accumulated nutrient in the process of desalinations and tended to become fertile;2) plant species diversity increased,whereas terrestrial insects and soil animals gradually replaced macrobenthos and waterfowl,which constituted the typical biological communities in coastal wetlands;3) land use transformed from natural land use to artificial land use,and the landscape pattern appeared to increase fragmentation and dominance index,while decreasing diversity;4) during the transition of natural wetland ecosystem to terrestrial ecosystem,the provisioning value increased and provisioning was the only growth ecosystem service,but its increment was lower than the reduction from regulating,cultural and supporting,leading to the loss of total value of ecosystem service;5) reclamation could increase ecological risk in terms of land and water resource security,biological invasion,natural hazard and other factors.Therefore,the trade-off between resource utilization and environmental conservation to realize the harmony between man and nature has been a key problem in coastal reclamation activity.Consequently,in the future,we should study the mechanisms underlying the effects of reclamation based on long-term stationary experiments for developing the meta-synthetic framework and integrated countermeasures system.In addition,further research on the effects of reclamation and exploitation on coastal eco-environment would be necessary.%沿海滩涂湿地生态系统,典型的生态脆弱区,既是地球表面最为活跃的自然区域,又承载着人类的生存与发展,其生态环境面临着巨大压力.在社会经济发展和人口增长的推动下,沿海国家大力从海洋中争夺陆地,围填海造地和围垦开发成为许多沿海地区和国家缓解人地矛盾的主要方法.在此背景下,对沿海滩涂围垦历史进行简述,从滩涂土壤性质、生物多样性、土地利用变化及景观格局、生态安全和生态系统服务等5个方面综述了人类围垦活动的生态环境影响.随着围垦时间的增加,滩涂土壤在脱盐过程中累积养分,逐渐熟化,土壤物理、化学和生物特性朝着有利于人类利用的方向变化;植物物种多样性呈不断增加的总体趋势,且随着生境的变化,陆生昆虫和土壤动物逐渐替代湿地典型的底栖动物和水鸟;土地利用方式从自然状态转变为以人工方式为主,景观格局表现为破碎化程度升高、多样性降低和优势度上升;从自然景观为主的自然湿地生态系统转为以人工景观为主的人工陆地生态系统过程中,供给服务的价值是唯一处于增长趋势的生态系统服务功能,但供给服务的价值增加量小于调节服务、文化服务和支持服务的减少量致使生态系统服务总价值降低,而且滩涂湿地面临着土地资源安全、水资源安全、生物入侵以及自然灾害加剧等风险.在全球气候变化背景下,如何权衡资源利用与环境保护并实现人与自然共生,是海岸带湿地生态系统在人类围垦活动中面临的重要难题之一.因此,未来应以机理研究为基础,以长期定位监测为手段,以综合集成的研究体系及对策制定为目标,不断深化沿海滩涂开发利用对生态环境影响的研究,为推动人类围垦活动下沿海滩涂湿地生态系统的可持续发展提供参考.
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