基于改进生态足迹模型的县域生态可持续评价

针对传统生态足迹模型（EFM，eco-footprint model）中存在诸多不足，提出了改进生态足迹模型（IEFM，improve eco-footprint model）的计算方法。从陕西省长武县实际资源消耗量与产量出发，对长武县2007年生态可持续性进行了计算和分析，并与EFM计算结果进行了比较。结果表明：1）长武县2007年人均生态足迹为0.29 hm2/人，人均生态承载力是1.23 hm2/人，人均生态盈余为0.94 hm2/人；2）长武县生态适度人口为7.208×105人，实际人口与生态适度人口的比例是0.24；生态利用效率为1.54 万元/hm2；3）长武县耕地、能源地的人均足迹占人均生态足迹的72%，林地和畜牧用地的人均足迹占人均生态足迹27%，人均建成地、水域、电力用地、垃圾排放用地的生态足迹仅占人均生态足迹的1.2%；4）长武县的人均足迹、人均承载力IEFM的计算值分别是EFM计算值的0.515倍和5.467倍；IEFM与EFM的生态赤字/盈余情况相反。长武县自然生态系统的压力处于生态承载力范围之内，生态系统处于可持续发展状态。

County-level ecological sustainability assessment based on improved ecological footprint model

According to the deficiencies of traditional EFM, in this paper, the improved EFM (IEFM) was discussed thoroughly. Changwu county of Shaanxi province was taken as the special region to validate the feasibility and usability of IEFM. The results showed that: 1) Ecological footprint per capita of Changwu county was 0.29 hm2, and ecological carrying capacity per capita was 1.23 hm2, thus the ecological surplus per capital was 0.94 hm2; 2) Ecological optimum population was 7.208×105, which the proportion to actual population was 0.24, Ecological efficiency (EE) was 1540 thousand yuan per hm2; 3) Arable land and fossil energy land of Changwu county made up 72% of ecological footprint per capita; Forestry and pasturage land made up 27% of ecological footprint per capita; Built-up land, electric power land, water area and other land make up 1.2% of ecological footprint per capita; 4) ecological footprint per capita and ecological carrying capacity per capita of the IEFM calculation were 0.515 and 5.467 times of EFM, and opposite conclusion was gained in the analysis of the ecological deficit/surplus. This showed that, pressure to natural ecosystems was within the ecological capacity, the ecological system of Changwu county was relatively safe and the whole economic development was in sustainable situation.