Abstract：
Agriculture accounts for 61 % of fresh water consumption in China. Although population and diet have a significant impact on water consumption, little is known about the reasons for and extent of their influence. Changes in the blue and green water footprint of 20 agricultural sectors in 31 Chinese provinces were estimated in 5 scenarios by applying the environmentally expanded multi-regional input-output model. The water footprint network is strongly interconnected, with over 50 % of the provinces characterized as net importers of the blue water footprint, 70 % of the total blue and green water footprint imports in developed provinces, and 65 % of the total blue and green water footprint exports in developing provinces, with the flow distribution driven and dominated by economically developed provinces. The findings also highlighted that the impact of population change on the water footprint is insignificant, contributing 0.51 % and 5.78 % to the reduction of the water footprint in 2030 and 2050, respectively. The impact of simultaneous changes in the population and dietary structure on the water footprint was higher than population changes and lower than dietary structure changes. The main force driving changes in the water footprint was changes in the dietary structure, which resulted in a two-fold effect on the water footprint. First, it has increased the blue and green water footprint by 33 % and 12 %, respectively, thus aggravating the coercive impact on water resources on the production side. Second, it has led to a change in the main contributing sectors for the blue and green water footprint from cereals to fruits, vegetables, and potatoes. Therefore, when the population is changing and optimizing its dietary structures, a greater focus must be placed on threats and pressures to water resources. This will result in better scientific management and more efficient use of water resources.
摘要：
农业占中国淡水消费量的61%。尽管人口和饮食对用水量有重大影响，对其影响的原因和程度知之甚少。通过应用环境扩展的多区域投入产出模型，在5种情景中估算了中国31个省20个农业部门的蓝色和绿色水足迹的变化。水足迹网络紧密相连，超过50%的省份是蓝水足迹的净进口国，发达省份蓝色和绿色水足迹进口总量的70%，发展中省份蓝色和绿色水足迹出口总量的65%，由经济发达省份驱动和主导的流量分布。研究结果还强调，人口变化对水足迹的影响微不足道，分别为2030年和2050年减少水足迹贡献0.51%和5.78%。种群和膳食结构的同时变化对水足迹的影响高于种群变化，低于膳食结构变化。水足迹变化的主要驱动力是饮食结构的变化，这对水足迹产生了双重影响。首先,它使蓝色和绿色的水足迹分别增加了33%和12%，分别,从而加剧了对生产侧水资源的强制性影响。第二,它导致了从谷物到水果的蓝色和绿色水足迹的主要贡献部门的变化，蔬菜,还有土豆.因此,当人口改变和优化其饮食结构时，必须更加关注水资源的威胁和压力。这将导致更好的科学管理和更有效地利用水资源。
