基于景观格局的海岛开发潜在生态风险评价

海岛生态系统是一种相对独立的生态系统,与岛外的信息交流比较少,甚至是没有,一旦对海岛造成损害是很难恢复的,因此,对海岛进行风险评价是海岛保护和管理的重要依据.海岛风险评价通常有两个方面,海岛自然灾害风险评价和海岛开发利用风险评价.针对海岛开发利用风险评价,应用遥感手段分析了海岛景观格局与海岛开发利用风险程度的关系,定义了海岛开发利用威胁指数和强度指数,建立了基于景观格局的海岛开发利用风险评价模型.然后,以2005年4月5日获取的5m分辨率的SPOT遥感影像为数据源,将提出的模型应用到渤海海域庙岛群岛中的大黑山岛、小黑山岛、北长山岛、南长山岛和庙岛进行评价,由现场调查情况分析可知评价结果是合理的.与传统的风险评价模型相比,本模型的优势在于应用遥感影像作为数据源,大大降低了对实地调查数据的需求.

Ecological risk assessment of island exploitation based on landscape pattern

Island ecosystem, as a relatively independent ecosystem having very little or even no communication with the mainland ecosystem, is difficult to recover after being destroyed, so ecological risk assessment is very important in island protection and management. In general, ecological risk assessments mainly focus on two kinds of risks, one induced by natural disasters and the other one caused by human exploitation activity. In this paper, aiming at the risk induced by human exploitation activity and using remote sensing method, we analyzed the relationship between island landscape pattern and island exploitation risk level, and introduced the threatening index and intensity index as the basic risk assessment indexes. Furthermore, an island exploitation risk assessment model based on the landscape pattern is constructed. At last, using the constructed model, we assessed the exploitation value-at-risks of some islands in Bohai Sea, including Daheishan Island, Xiaoheishan Island, Beichangshan Island, Nanchangshan Island, and Miao Island, on the basis of the 5m-resolution SPOT image on 5th April, 2005. The assessment results are consistent with the in-situ survey data. Compared with general ecological risk assessment models, the remote sensing data-based island exploitation risk assessment model constructed in this paper greatly reduces the necessity of in-situ survey data.