数据来源：生态环境部、各省市生态环境厅（局）、流域水利委员会
中国以外国家水质数据来源：United Nations Environment Programme (2017). GEMStat database fo the Global Environment Monitoring System for freshwater (GEMS/Water) Programme. International Centre for Water Resources and Global Change, Koblenz. Accessed 26 August 2021. Available upon request from GEMS/Water Data Centre: gemstat.org