中文摘要：

近年来,随着机动车保有量的增加,机动车源成为导致大气颗粒物污染的主要源类之一.机动车源对大气细颗粒物（PM（2.5））的浓度贡献,以及如何准确评估机动车源贡献是目前亟需解答的问题.本研究在调研已有文献研究的基础上,总结了目前机动车源贡献评估的主要方法,包括基于源清单信息的方法、受体模型法、化学传输模型法、混合源解析方法等,阐释了各种方法的原理与应用,评述了各种源解析方法的优势与存在的问题;此外,总结了国内不同城市（尤其是北京市）机动车源对细颗粒物的贡献,指出了定量机动车源贡献中面临的挑战与尚待解决的问题.

英文摘要：

China is facing serious haze problems due to the levels of fine particulate matter（PM（2.5））. Therefore, source apportionment of PM（2.5） is required for formulating effective air pollution control strategies. The fast increase of the vehicle population, especially in the megacities of China in recent years, makes vehicular emissions one of the most important sources of PM（2.5） and has led to it receiving great attention and concern. There is an urgent need to accurately and quantitatively estimate the contribution of vehicular emissions. A growing number of studies have been conducted for source apportionment of PM（2.5） in China and report the contribution from vehicular emissions using different methods. However, it is still a big challenge as to how vehicular emissions can be accurately quantified. This study summarizes the various methods that have been used to identify and quantify the vehicular emissions contribution to PM（2.5） in published literature by international and domestic scientists, lists advantages and disadvantages of each method, and proposes ways to reduce its uncertainty. In general, methods for estimating vehicular emission contributions in previous studies include emission inventory based methods, chemical transport models, receptor models, hybrid models etc. The receptor model based method is the most commonly applied method in China. Source profiles of vehicular emissions based on source testing in China, and organic and inorganic tracers used for diagnosing vehicular emissions, which are two key factors for quantifying vehicular exhaust in receptor models, are also summarized here. Contributions of vehicular emissions to ambient PM（2.5） reported in different areas in China, especially Beijing, are listed and compared. It can be seen that the contribution of vehicular emissions to PM（2.5） varies significantly with the study area, year of the study, as well as the methods in use. The vehicular emissions contribution to PM（2.5） in Beijing is reported to be