摘要
基于生态服务功能与土地利用/覆被变化(LUCC)的安全评价是当前地理学和生态学研究的热点,如何将二者的研究有机地结合并对区域生态安全评价实现具有时间动态、空间可视的四维表达是方法论和认知角度的新尝试。论文在G IS技术的支持下以栅格数据和生态系统服务价值为评价基础,在采用Costanza生态系统服务价值修正值的基础上对张掖绿洲从不安全、较不安全、稳定、较安全和安全等5个级别进行了生态安全评价。结果表明,在1985—1995年,张掖绿洲生态价值损失了0.193×108元,1995—2006年损失1.933×108元,生态安全状况趋向恶化。处于稳定状态的斑块类型面积由92.91%减小到88.53%,减少的部分大多转换为较安全和不安全状态二种类型。从不同安全级别的斑块格局来看,稳定类型的平均斑块面积从1985—1995年到1995—2006年减少了905 hm2,而斑块数量却增加了349个;5个级别的斑块形状指数和连通度在整个研究时期变化趋势一致,即:形状指数越来越高,而连通度指数越来越低,说明整个张掖绿洲在安全级别类型格局上呈破碎化趋势,不同级别斑块相互交错。
Security assessment of relationship between ecosystem service functions and land use and land cover change（LUCC） is one of the focuses in geographical and ecological study in recently decades.From the perspective of methodology and cognition,it is a new attempt to incorporate this relationship into regional assessment of ecological security and thereby realize its four dimentional expression,variable and visual in temporal and spatial scales.Based on raster data and the modified ecosystem service values that originally attached economic values in world ecosystems by Costanza and consequently modified in Chinese ecosystems by Xie,this paper employed the GIS technique and the modified ecosystem service values to evaluate the ecological security status which are divided into non-safe,relatively non-safer,stability,relatively safer,and safe categories on two periods between 1985 to 1995,and 1995 to 2006 in Zhangye Oasis.Findings showed that ecological values lost about 0.193×108 RMB yuan between 1985 and 1995 and 1.933×108 yuan between 1995 and 2006,respectively,suggested that ecological security situation becomes worse during the whole study period in Zhangye Oasis.Stability type as a dominant category,its percentage of occupied total study area decreased from 92.91% to 88.53% between the two periods,and most part of this decreased area was converted into relatively safer and non-safe types.In terms of patch patterns of different safety levels,the mean patch area of the dominant type decreased 905 hm2 from the period of 1985-1995 to the period of 1995-2006,whereas its patches number increased 349 also.During the whole study period,patch shape index and patch connectivity for the five categories presented similar variation patterns to each other,i.e.the shape index became higher and higher while the connectivity index became lower and lower,indicating that all the safety types classes in Zhangye Oasis exhibited a trend of fragmentation as a mosaic landscape composed of different patches.
出处
《自然资源学报》
CSSCI
CSCD
北大核心
2010年第3期396-406,共11页
Journal of Natural Resources
基金
国家重点基础研究发展计划"干旱区绿洲化
荒漠化过程及其对人类活动
气候变化的响应与调控(2009CB421302)"
鲁东大学学科建设项目
