Imbalance in the city-level crop water footprint aggravated regional inequality in China

Qian Wang; Guangyu Zheng; Jixuan Li; Kai Huang; Yajuan Yu; Shen Qu

doi:10.1016/j.scitotenv.2023.161577

Imbalance in the city-level crop water footprint aggravated regional inequality in China

Sci Total Environ. 2023 Apr 1:867:161577. doi: 10.1016/j.scitotenv.2023.161577. Epub 2023 Jan 11.

Authors

Qian Wang¹, Guangyu Zheng¹, Jixuan Li¹, Kai Huang², Yajuan Yu³, Shen Qu⁴

Affiliations

¹ Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
² Beijing Key Laboratory for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China. Electronic address: huangkai@bjfu.edu.cn.
³ Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science & Engineering, Beijing Institute of Technology, Beijing 100081, China.
⁴ School of Management and Economics, Beijing Institute of Technology, Beijing 100081, China; Center for Energy and Environmental Policy Research, Beijing Institute of Technology, Beijing 100081, China.

PMID: 36638997
DOI: 10.1016/j.scitotenv.2023.161577

Abstract

Crop production is the main consumer of water resources. The heterogeneous water resource endowments and imbalanced crop water use exacerbate regional resource consumption inequality. In this study, we quantified the crop water footprint (CWF) of 356 cities in China from 2000 to 2020, measured the inequality between the city CWF and water resources, and identified different strategies to alleviate regional CWF inequality. We found that the average CWF from 2000 to 2020 varied widely across cities, ranging from 0.03 × 10⁸ m³ to 806.78 × 10⁸ m³, and the inequality between city CWF and local water resource endowment was increasing. China had a strong dependence on green water in crop production, and its proportion increased from 52.48 % to 67.17 %. The Gini coefficient of the green water footprint increased from 0.545 to 0.621, and the degree of inequality increased significantly. In addition, the blue water and gray water continuously showed great inequality, especially the blue water, the Gini coefficient of which was 0.724 in 2020. The results show significant disparities in CWF among cities, which have highly exacerbated regional inequality in China. Improving the utilization rate of green water is an important measure to balance the allocation between serving the natural ecosystem and meeting the basic human needs. This study revealed for the first time the inequality of city-level CWF and highlights the severe situation of inequality among regions in China. Balancing the inequality between CWF and water resource endowment at city-level is conducive to fundamentally solving the problem of unreasonable water resource allocation.

Keywords: China; City level; Crop water footprint; Inequality; Influence factors.