城镇居民食物消费的生态足迹及生态文明程度评价

城镇居民食品账户生态足迹核算一直面临着消费项目不完善与消费-土地利用矩阵信息匮乏的问题。研究通过改进自下而上生态足迹模型,较好地解决了上述问题;并构建了食物消费的生态文明度概念与分类层次体系,在生态影响“数量”评估的基础上开展了“质量”评估。论文对2005—2012年中国及各省城镇居民食物消费的生态影响及生态文明度进行了实证研究,结果表明：1）城镇居民部门食物账户的生态影响变动主要驱动力为在外就餐;2）全国及大陆省份中除山西、江西和青海外的28个省份城镇居民食物消费的生态文明度发生了不同程度的下降。中国如果忽略城镇市场倒逼机制对生态文明的巨大作用,规模扩大与食谱增富的城镇化可能将整个中国带入生态环境脆弱性增强的境地。

Footprint and Degree of Ecological Civilization Assessment of Chinese Urban Food Consumption

China’s urban household food consumption has significantly changed over the last decades. China has already begun to enter the primary city-based society with urban population projected to about 70% of the country’s population by 2030. During the urbanization, food consumption pattern involved in urban areas has been increasingly determining the fate of ecological civilization development for China, as in many other countries. Ecological footprint analysis estimates the “load” imposed on the ecosphere by human population and activities. Few but risen studies used it to measure the impact we pin on nature by making green food consumption policy. The Ecological Footprint of Foods (EFF) consumption by urban households is usually accounted using bottom to up footprint methodology. The incomplete food items list and the incomplete consumption-land use matrix are two key limits that significantly affect the accuracy of EFF. We modified the input-output technique based on footprint account model. Firstly, we make the food items list as complete as possible. The new list involves 30 food items consumed at home (FH), about 50% more than most of the published study, with food away from home (FAFH) traced. Secondly, the consumption-land use matrix for every item is accounted by using material flow analysis. The completeness and accuracy therefore could be improved significantly. We also develop a new concept, Degree of Ecological Civilization (DEC), to reveal the quality of EFF. DEC is defined as an indicator depicting the ecological rationality and sustainability of the impact that a defined food consumption pattern imposes on nature. DEC is disaggregated into five hierarchies (very high, high, medium, low and very low) by balancing EFF and two benchmark indicators, bio-capacity required by balanced diet pattern and national average bio-capacity available per capita. We applies the modified footprint account model and new DEC system to China in period 2005-2012, at both national and provincial scales, to measure the impact of human’s change of diet pattern on nature. FAFH contributes rising percentage of total EFF in national and provincial urban households, rocketing to 40% in 2012. Obviously, FAFH has already overridden FH as the key force driving EFF change. DEC degraded at national scale and in 28 of 31 provinces, indicating higher and universal ecological risk. The urban therefore must take corresponding responsibility.