<P> Natural color satellite image of a smog event in the heart of northern China </P> <Li> <P> Dense smog settled over the North China Plain on February 20, 2011 . </P> </Li> <P> Dense smog settled over the North China Plain on February 20, 2011 . </P> <P> Air pollution (sulfur dioxide particulates) from reliance on coal is a major issue, along with water pollution from untreated wastes and use of debated standards of pollutant concentration rather than Total Maximum Daily Load . There are water shortages, particularly in the north . The eastern part of China often experiences smoke and dense fog in the atmosphere as a result of industrial pollution . Heavy deforestation with an estimated loss of one - fifth of agricultural land since 1949 to soil erosion and economic development is occurring with resulting desertification . China is a party to the Antarctic - Environmental Protocol, the Antarctic Treaty, the Convention on Biological Diversity, the Climate Change treaty, the United Nations Convention to Combat Desertification, the Endangered Species treaty, the Hazardous Wastes treaty, the Law of the Sea, the International Tropical Timber Agreements of 1983 and 1994, the International Convention for the Regulation of Whaling, and agreements on Marine Dumping, Ozone Layer Protection, Ship Pollution, and Wetlands protection . China has signed, but not ratified, the Kyoto Protocol (but is not yet required to reduce its carbon emission under the agreement, as is India) and the Nuclear Test Ban treaty . </P>

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