基于土地利用变化和生态系统服务的海岸带生态安全综合评价——以胶州湾为例

以土地利用为主的陆域开发活动能改变近海环境质量,并影响和改变原有海岸带生态系统服务功能的供给模式,对海岸带生态安全产生一定的负面影响.目前在海岸带生态系统研究领域较多采用陆地生态系统研究模式,未能真正体现海岸带作为海陆结合的独立的环境体系的特点,并缺乏对陆域活动驱动与生态系统服务功能响应和生态安全实现之间复杂关系的科学解释.本研究基于海岸带生态系统服务的空间异质性和流动性特点,以“土地利用变化(LUCC)-生态系统服务(ES)-生态系统安全”为研究主线,构建海岸带生态安全评价模型,探讨以土地覆被变化为主的陆域活动对海岸带生态系统服务功能和区域生态安全的影响机理及其时空变异规律.从模型的评价结果上看,作为生态安全系统中主要压力表征的胶州湾陆域土地利用变化,与相应海域内的生态系统服务状况和生态安全状态呈现出一定的相关性和趋势性.随着环胶州湾地区城市化进程中大量用地流转为城乡建设用地,胶州湾中相应海域的生态系统服务状态下降,进而带来该海域生态安全状态恶化.本文所提出的基于压力-状态-响应(PSR)框架的海陆结合的生态安全评价模型,以探讨陆域活动对海岸带生态系统服务功能和区域生态安全的影响及其时空变异规律为目的,可以克服目前研究中只关注陆域部分而忽视陆域活动与海域部分之间的联系和相互影响的缺陷,对海岸带生态安全评价研究具有一定的改进作用.

Integrated assessment of coastal ecological security based on land use change and ecosystem services in the Jiaozhou Bay,Shandong Peninsula,China

Land use-based development activities can change the quality of coastal environment and the supply pattern of ecosystem services, negatively affecting the ecological security of coastal zones. Coastal ecosystem research has generally used terrestrial ecosystem research models which cannot actually reflect the features of the coastal zone—An independent environmental system combining land and sea. A scientific explanation is lacking for the complex relationship among driving factor of land-based activities, the response of ecosystem services, and the realization of ecological security in the coastal zone. Here, we presented an integrated assessment model for coastal ecological security that was established following the route of “Land use-Ecosystem services-Ecological security” and considering the spatial heterogeneity and mobility of coastal ecosystem services. The proposed model was used to assess the impacts of land use-based activities on coastal ecosystem services and regional ecological security and reveal the associated spatiotemporal variations in the Jiaozhou Bay, Shandong, China. Land use change around Jiaozhou Bay, as the main representation of pressure in the ecological security system, exhibited certain association and tendency with the states of ecosystem services and ecological security in the corresponding sea area. Owing to massive land transfer to built-up lands during urbanization, the ecosystem services declined in the sea areas of Jiaozhou Bay and thus resulted in the deterioration of coastal ecological security. The integrated assessment model of coastal ecological security based on pressure-state-response (PSR) frame could effectively reflect the spatial distribution and trends of coastal ecological security. Meanwhile, this model could clarify the response relationship of ecosystem services and ecological security in the sea portion with the land-based driving factor, i.e., land use, in the coastal ecosystems. Unlike the methods commonly used in previous studies on coastal ecological security, the model established here overcomes the shortcomings of others that only focus on the land portion and ignore the link and interaction between the land and sea. This model was therefore of improvement to the evaluation of coastal ecological security.