食物价格对改善居民膳食结构及降低水资源需求的作用机制

Price mechanism for improving dietary structure and reducing the pressure on water resources

价格工具在改善居民膳食结构与降低食物生产用水压力两个方面,发挥着重要作用。本文基于1781户微观家庭的记账式调研数据,构建了2-Step QUAIDS食物需求系统模型,估计了中国城市居民食物消费结构的变化趋势;在此基础之上,模拟了不同价格方案对膳食结构和水资源需求的影响。结果表明:①中国居民膳食结构将持续以肉类消费占比上升为主要特征的变化趋势。一方面,这种变化将进一步推升居民家庭的食物消费水资源需求;另一方面,由于对当前消费占比本就偏低的蔬菜以及包括乳制品在内的其他食物的挤出,居民膳食结构的失衡程度将进一步加大,影响健康水平。②肉类食品合理的价格管理方案在降低水资源需求的同时,将推动城镇居民膳食结构的均衡化。在家消费的肉类价格上升10%,将会使城镇居民食物消费水足迹期望值下降5.32%,此情境下,消费者通过减少肉类消费,增加蔬菜以及其他食品(包括乳制品、豆制品等)消费,使得其膳食结构偏离均衡模式百分点数由24.80减少到19.61,居民膳食结构得以改善。面对快速增长的超重及肥胖发生率和持续增加的农业水资源压力,科学探求并合理利用食物价格机制,以此实现改善居民膳食结构并减少农业水资源压力的双赢目标,具有重要的现实意义。

Price tools play an important role in improving dietary structure and reducing water resources pressure.This study built a 2-Step QUAIDS food demand system model based on the micro level book-entry survey data of 1781 households and estimated the effect of price on the food consumption structure of urban residents in China.On this basis,the study simulated the influence of different price schemes on the water demand for food consumption and the dietary structure of residents.The results show that:(1)With the increase of income,the proportion of meat and fruit consumption in household dietary structure is raising and will continue to increase in the future.Without intervention,such a change,on the one hand,will further promote household demand for food consumption related water resources;on the other hand,it will also increase the imbalance of residents’dietary structure,affecting their health condition.(2)Reasonable price mechanism is feasible to improve the dietary structure of residents and reduce the pressure on water demand caused by food consumption.A 10% increase in the price of meat consumed at home will reduce the expected value of water footprint of residents’food consumption by 5.3%.At the same time,this measure will improve the unbalanced state of residents’dietary structure.In the face of the rapid growth of overweight incidence and the increasing pressure on agricultural water resources,using the price mechanism to achieve the goal of improving people’s dietary structure and reducing the pressure on agricultural water resources has important practical significance.