Water Security Research Centre, School of International Development, University of East Anglia , Norwich, NR4 7TJ, U.K.
Environ Sci Technol. 2014 Oct 7;48(19):11048-56. doi: 10.1021/es501379n. Epub 2014 Sep 29.
China is a country with significant but unevenly distributed water resources. The water stressed North stays in contrast to the water abundant and polluted South defining China's current water environment. In this paper we use the latest available data sets and adopt structural decomposition analysis for the years 1992 to 2007 to investigate the driving forces behind the emerging water crisis in China. We employ four water indicators in China, that is, freshwater consumption, discharge of COD (chemical oxygen demand) in effluent water, cumulative COD and dilution water requirements for cumulative pollution, to investigate the driving forces behind the emerging crisis. The paper finds water intensity improvements can effectively offset annual freshwater consumption and COD discharge driven by per capita GDP growth, but that it had failed to eliminate cumulative pollution in water bodies. Between 1992 and 2007, 225 million tones of COD accumulated in Chinese water bodies, which would require 3.2-8.5 trillion m(3) freshwater, depending on the water quality of the recipient water bodies to dilute pollution to a minimum reusable standard. Cumulative water pollution is a key driver to pollution induced water scarcity across China. In addition, urban household consumption, export of goods and services, and infrastructure investment are the main factors contributing to accumulated water pollution since 2000.
中国是一个水资源分布不均的国家。水资源紧张的北方与水资源丰富但污染严重的南方形成鲜明对比,构成了中国当前的水环境。本文利用最新的数据集,采用结构分解分析方法,对 1992 年至 2007 年期间中国日益严重的水危机的驱动因素进行了研究。我们采用了中国的四个水指标,即淡水消耗、污水中 COD(化学需氧量)的排放量、COD 的累积量和用于累积污染的稀释水量,来考察引发这场水危机的驱动因素。研究发现,水强度的提高可以有效抵消人均 GDP 增长带来的年度淡水消耗和 COD 排放量的增加,但未能消除水体中的累积污染。1992 年至 2007 年间,中国水体中累积了 2.25 亿吨 COD,要将其稀释到最低可重复利用标准,需要 3.2 万亿至 8.5 万亿立方米的淡水,具体取决于受纳水体的水质。累积水污染是导致中国水污染型缺水的关键因素。此外,自 2000 年以来,城市家庭消费、货物和服务出口以及基础设施投资是造成累积水污染的主要因素。