大城市居民生活消费的生态占用初探——对北京、上海的案例研究

ECOLOGICAL FOOTPRINT OF LIVING CONSUMPTION PER CAPITA IN METROPOLIS:A CASE STUDY OF BEIJING AND SHANGHAI

生态占用方法是通过跟踪人类利用的大多数消费品和产生的废弃物 ,来计算生产和维持这些消费及同化废弃物所需要的生物生产性土地面积 ,并与生态承载力进行比较 ,以此衡量可持续发展的程度。该文运用生态占用分析方法 ,以北京市、上海市为例 ,估算了 1 999年两市居民的食物、衣着、生活用品、生活用能等主要生活消费占用的生态空间。两市居民人均生态占用面积分别为 1 62hm2 和 1 3 3hm2 ,其中存在由于地方生活习惯差异造成的生态占用面积及类型的差异。虽然估算相对保守 ,但全市居民生态占用的总面积已经数十倍于城市实际面积。城市显然是“生态赤字”区 ,城市居民依赖于城市边界之外的生态系统满足基本生活需求。随着我国今后城市化步伐的加快 ,城市可持续发展问题将越来越重要 ,开展城市生态占用这一科学问题的研究也变得十分紧迫和重要。

Ecological footprint is suggested to offer a conceptual framework and methodology to evaluate sustainability. The ecological footprint is described with the area of productive areas and water ecosystems, which is necessary to produce the resources that people consume and to assimilate the wastes that people output.The ecological footprint of major living consumption per capita in Beijing and Shanghai in 1999 is presented in this paper. First, the consumption is estimated for each relevant category, which includes food, clothing, household facility, fuel and housing. Second, the productive area is estimated for different land categories. The productive land area, including fossil energy land, arable land, pasture, forest, built up areas and sea, are calculated with average yields and adjusted with equivalence factor. Finally, all area figures are summed. The results indicate that the ecological footprint per capita in Beijing and Shanghai is 1.62 hm 2 and 1.33 hm 2, respectively. The differences of ecosystem footprint between Beijing and Shanghai can be ascribed to the diverse living habits and customs within two cities. To accommodate the urban residents, the ecological footprint for Beijing and Shanghai would be 22 and 57 times larger than their territories. Accordingly, it is apparent that city is the area of ecological deficit, and the ecosystems upon which the residents depend are beyond their home territories. Therefore, to develop the sustainable city, we should consider the capacities of ecosystems and advocate the ecological ways of life and consumption.