بازده سوخت و انتشار در بخش حمل و نقل جاده چینی: اثر منجر شده و اثر بازپرداخت  Fuel efficiency and emission in China’s road transport sector: Induced effect and rebound effect

1. Introduction Urbanization is the focus of China’s economic and social development during “the 13th five-year plan” and under the new economic policies, and is also the grand strategy and the long-term driving force for expanding domestic demand. Promote new urbanization is the main way to improve China’s sustainable economic development recently, urbanization is associated with large scale movements of the labor force from the country side into urban areas the result of which is to increase population density in the urban areas. The relationship between urbanization and fuel consumption has been studied by a number of authors (Sadorsky, 2013; Karathodorou et al., 2010; Kim and Brownstone, 2013; Liddle, 2004; York, 2007), Sadorsky (2013) indicated that the impact of urbanization on energy intensity is mixed, while Karathodorou et al. (2010) found that urban density affect fuel consumption through variations in the vehicle stock and in the distances traveled mostly, rather than through fuel efficiency. Kim and Brownstone (2013) found that residential density has a statistically significant but economically modest influence on vehicle usage, lower neighborhood residential density induces consumer choices toward less fuel-efficient vehicles. Liddle (2004) found that urbanization and population density have a negative impact on per capita road transportation energy use. York (2007) estimates the urbanization elasticities of fuel consumption vary between 0.29 and 0.56 in the European Union. In the process of promoting urban development, the increase in population density puts stress on the local environment (Sadorsky, 2013), the potential of traffic demand will materialise and fossil fuels’ consumption will continually aggravate the urban air pollution, which brings severe challenges to sustainable economic development of China. The conflict between reliance of economic development on road traffic and the increasingly severe pollution caused by exhausts of road traffic, is the main obstacle to sustainable development of road traffic in China. According to the National Bureau of Statistics of China, the consumption of oil in the transport sector accounts for 50% of the country’s total oil consumption and road traffic is the most rapidly growing transportation mode. Beijing Environmental Protection Bureau proved that motor vehicle exhaust emissions account for 31% of the local PM2.5 sources in Beijing and are the largest source of pollution. Data of the traffic management bureau of the public security ministry show that the average annual growth rate of vehicle ownership has been 17.7% since 2001. Road transport system is becoming one of the largest and most rapidly growing oil consumers in China (He et al., 2005), resulted in serious air pollution and residents’ health (Yang and He, 2016) which has become a major problem to realize China’s new urbanization path and sustainable economic development. How can we effectively control air pollution caused by road traffic without affecting economic growth? Economic development of China depends on unceasing increase in total transportation, but by increasing the road mileage meanwhile improving the transportation fuel economy and efficiency, can China’s road traffic achieve low-vehicle carbon green development? More specifically, economic development will increase along with the road mileage (Yang and He, 2016; Kayser, 2000; Burke and Nishitateno, 2013; Huo et al., 2012; Ma et al., 2015), or road infrastructure precisely, when the supply of road infrastructure increases and road capacity is improved, it will attract new road traffic demand (Asensio et al., 2014; Gallego et al., 2013), and further generate new consumption of fossil fuels and exhaust emissions, which can be called as induced effect, generated by road traffic infrastructure. In order to control the air pollution, the policymaker formulate the corresponding policy to deal with, in Beijing where the haze problem is the most prominent has unveiled policies such as “The Regulations for the Control of Air Pollution of Beijing”, “Beijing 2013–2017 Clean Air Action Plan”, with main measures striving to develop public transport, conducting strict regulation of the total motor vehicles, pushing the vehicle structural optimization and adjustment, accelerating the elimination and updating of old vehicles, improving public management policies and automobile oddand-even license plate rule and other emergency measures are taken in severe haze periods to respond to this issue. By adjusting the structure of travel modal, these traffic energy polices have reduced the proportion of high energy consumption travel modal and increased the environment-friendly travel modal, which improved the fuel efficiency of road traffic department and reduced unit mileage costs, as well as the role of technical progress of road traffic. However, the improvement of fuel efficiency have also increased vehicle usage, and thus have further generated new fossil fuel consumption and exhaust emissions, which can be called as the rebound effect (Clerides and Zachariadis, 2008), generated by the road traffic energy policies and technical progress of road traffic.