1. Background 背景
近年来，北京的空气污染非常严重。1998，北京地区总悬浮颗粒物、二氧化硫、氮氧化物的平均浓度分别为百分之89、百分之100，高于全国空气质量第二标准。根据空气质量的对比分析，在45个国家，157个城市（包括在中国44个主要城市）由中国国家环境监测中心进行的，北京的空气污染指数排名7位，排名1995
With the development of economy, the environmental pollution directly affects people's quality of life and environmental quality issues are gaining the common concerns. The environmental pollution includes water pollution, air pollution, solid waste pollution, etc. The air pollution commonly occurs in the urban area due to the impacts of industrial production and resident living. Several historical severe pollution incidents such as the London smog, Los Angeles photochemical smog events all took place in the big cities.
In recent years, Beijing's air pollution is very serious. In 1998, the average concentrations of total suspended particulates, sulfur dioxide, nitrogen oxides in Beijing are 89 percent, 100 percent 204 percent higher than the national air quality second standards, respectively. According to the comparative analysis of air quality on 45 countries, 157 cities (including 44 major cities in China) conducted by China National Environmental Monitoring Centre, air pollution index of Beijing ranked No. 7 in 1995; and ranked No. 3 in 1998. The total suspended particulates and sulfur dioxide of Beijing was respectively 25% and 62% higher than that of Mexico City, in which the air pollution was most serious. In addition, the air pollution index of Beijing was 40 percent, 33 percent and 37% percent higher than that of Shanghai, Tianjin and Chongqing city in China. Beijing’s atmospheric pollution is caused by many reasons, including not only the long-term historical factors but also the issues caused by the recent development. The major origins of the air pollution are the combustion of 28 million tons of coal per year, the exhaust of more than 140 million vehicles, and dust raised by more than 5,000 construction sites and natural dust and so on.
Lands use plays a key role in the regional environmental issues. It is especially important for the studies about the pollutant emission inventory. But at present, the studies about the quantitative relationship between the different lands use types and the emissions of air pollutants, particularly the pollutant emission characteristics of different lands use types (the underlying surface types) in urban area have not been conducted systematically.
2.1 Study area
2.2.2 Emission Inventory of Beijing city
2.2.2.1 The description about the emission Inventory
2.2.2.2 Emission Inventory of Beijing city
2.2.3 The quantitative relationship between pollution sources and their emissions and lands use in Beijing city
References cited
