Environment statistics on air emissions , air quality , water resources , water pollution and quality of selected rivers , lakes and coastal areas , waste generation and treatment , land use and land degradation mainly for 1990-2000 . Under contract with the Secretariat , trade data are held and monitored by the United Nations Environment Programme -World Conservation Monitoring Centre ( UNEP-WCMC ) , Cambridge , United Kingdom ( http : //www.unep-wcmc.org ) .