中国主要省会城市水资源生态足迹与适宜承载人口规模

Water Resource Ecological Footprint and Suitable Carrying Population Size in Provincial Capitals of China

[目的]评估中国主要省会城市的水资源承载情况与适宜人口规模,为“以水定人”政策的落实和城市可持续发展战略的实施提供参考。[方法]基于水资源和人口数据,采用生态足迹方法分析了2010—2020年中国省会城市的水资源生态足迹及其水资源承载力,结合生活用水现状以定额法估算了各省会城市的适宜承载人口规模。[结果]①超过半数省会城市年人均水资源占有量不足500 m 3,多数城市生活用水占总用水量的两成,而北京市和郑州市的生活用水比例达到45%,高比例的生活用水使城市供水压力巨大;②人均水资源量较高的省会城市呈现水资源生态盈余状态,但约2/3的城市呈现水资源生态赤字状态;2010—2020年平均人均盈余最高者为南宁市(2.20 hm^(2)/人),赤字最高者为银川市(-1.66 hm^(2)/人);水资源生态盈亏分布呈现“南方盈余,北方亏损”的格局,但是长江中下游地区部分省会城市也呈现赤字状态;③以“粗放”与“节约”两种用水情形评估省会城市适宜承载人口数量。各地适宜承载人口数量与现状人口数量存在较大差异。[结论]为促进经济社会可持续发展,水资源浪费严重的城市应当加强节水城市建设,而居民生活用水标准较低的城市应考虑减小其人口规模以提升居民用水体验与生活质量。

[Objective]The water resource carrying capacity and appropriate population size of main provincial capitals in China were analyzed in order to provide a reference for implementing the policy of“determining population by water resources”and the strategy of urban sustainable development.[Methods]Based on water resources and population data,we used the ecological footprint method to analyze the ecological footprint of water resources and their water resource carrying capacity in the provincial capital cities of China from^(2)010 to 2020.The quota method was used with current domestic water consumption data to estimate the suitable carrying population scale for each provincial capital.[Results]①More than half of the provincial capitals had less than 500 m 3 of water per capita per year,and the domestic water consumption of most cities accounted for 20%of the total water consumption,while the domestic water use of Beijing City and Zhengzhou City accounted for 45%of the total water consumption.This high proportion of domestic water use put the urban water supply under great pressure.②Cities with high per capita water resources have an ecological surplus of water resources.However,about two-thirds of the provincial capitals were in a state of ecological deficit.The highest per capita surplus from^(2)010 to 2020 was found for Nanning City(2.20 hm^(2)/person).The greatest per capita deficit was found for Yinchuan City(-1.66 hm^(2)/person).The distribution of ecological surplus and deficit of water resources showed a pattern of“surplus in the south,deficit in the north”,but some provincial capitals in the middle and lower reaches of the Yangtze River also showed deficits.③The suitable population in provincial capitals was evaluated based on the two water consumption scenarios of“extensive consumption”and“conservative consumption”.There was a large difference between the suitable population and the current population.[Conclusion]In order to promote sustainable economic and social development,cities with serious waste of water resources should strengthen the construction of water-saving cities,while cities with low domestic water standards should consider reducing their population in order to improve the water using experience and the quality of life of residents.