区域土地资源生态安全评价的物元模型构建及应用

Matter-element model and its application to land resource eco-security assessment

针对区域土地资源生态安全的特点,基于P-S-R模型和层次分析法建立了土地资源生态安全评价的指标体系,采用物元和可拓理论构建了区域土地资源生态安全评价的综合评判模型,并以宁夏南部彭阳县为例进行了实证研究.研究结果表明①研究区域1986年—2004年近20年以来土地资源生态安全状态有改善的趋势,但是整体水平并不容乐观,目前仍处于临界安全水平.②评价结果符合当地实际情况,物元模型克服了评价过程中人为因素的影响,通过对参评因子的量化处理,实现了评价精度的提高,应用物元模型进行土地资源生态安全评价可行、客观,可作为土地资源生态安全评价的一种新方法.③物元模型作为正在蓬勃发展的数学工具,无论在理论体系方面还是在实际应用中都存在着不完善的地方,例如目前可供选择的关联度函数较少,因此物元模型在土地资源生态安全评价中的应用也需要进一步深入研究和扩展.

Focusing on the characteristics of regional land resource eco-security and main eco-problems of land ecosystem in loess hilly area, an index system was established based on pressure-state-response framework and analytic hierarchy process （AHP）. And an integrated assessment model was constructed with the support of matter-element model and extension engineering theory. The assessment model was applied to Pengyang county, a typical loess hilly area, located in northwest of China. The results indicate that condition of land eco-security of study area showed improved trend from 1986 to 2004, while it still means to be under a critical security level nowadays; Overall results obtained by such model are basically consistent with the local condition, which illustrates that the integrated assessment model is reliable and feasible, and can be used as a new method to evaluate land eco-security. However, as a developing math tool, the matter-element model also has some flaws, such as few correlation functions available etc., so further research and analysis should be done to improve its application to the land eco-security assessment and ongoing refinement and constructive feedback are sought from practitioners.