Water use inequality and efficiency assessments in the YangtZe River Economic Delta of China

Abstract

The Yangtze River Economic Delta (YRED) faces inequality in water use in large proportions due to rapid industrialization. This study adopted the Gini coefficient and Global Moran's index to calculate inequality, its spatial spread and water use efficiency of cities in the YRED and categorized them into types based on the spatial spread of inequality. In general, inequality is reducing, but water use efficiency is poor. Inequality was rated 0-1; zero being the highest equality while 1 indicates the highest inequality. There is relatively high inequality (0.4-0.5) in Shanghai, Suzhou and Hefei. Most cities (20), however, showed equality (below 0.2). Nine (9) cities showed relative equality (0.2-0.3), while Wuxi, Bengbu and Zhenjiang were neutral (0.3-0.4). No city scored above 0.5. Water use efficiency in the majority of cities was poor. Only 11 out of 35 cities scored more than 50% efficiency. Poor irrigation, income and industrial water demand are the factors driving inefficiency and inequality. The categorization of cities into groups produced nine city types according to the spatial disposition of inequality. A combined effort to formulate policies targeting improved water use efficiency, reduced industrial consumption and improved irrigation, tailored towards the specific situation of each city type, would eliminate inequality.