congestionpricingandsustainabledevelopmentofurban-外文文献(编辑修改稿)

congestionpricingandsustainabledevelopmentofurban-外文文献(编辑修改稿)内容摘要：

residence, so retail firms cannot easily move out of the core area, because so many people live in center area. This dependence on customer convenience explains why retail production decreases less than the output of other primary industries in the core area. Congestion pricing reduces congestion during the peak time and increases congestion during other periods. By shifting toward public transit and high occupancy vehicles, congestion pricing reduced the number of trips to the pricing areas across all time periods. Except reduced congestion, if improvement of air quality and decrease of fuel consumption are taken into account, the economic efficiency resulting from congestion pricing would be considerable. 3. Environmental protection In China, environmental problem bee increasingly serious. It was reported that china is the second emitter of CO2, and 7 cities are in the list of seriouslypolluted cities in the world. The environmental effects of transportation cover a wide range of different impacts, including for example air 450pollution, noise, and climate change. Motor vehicles are the dominant producers of urban air and noise pollution, including carbon monoxide, oxides of nitrogen, and airborne particulates. These pollutants are key factors in many respiratory ailments such as asthma as well as “a range of other human health effects, from headaches and eye irritation to cancer” [8]. The World Bank estimates that million people in developing countries die each year from transportrelated air emissions, with a similar death toll from traffic accidents [9]. Transportation cannot be replaced because it is the part of the production chain. For this reason, transportation systems must be developed and standardized, the effectiveness of transportation service must be increased, while the environmental pollution must be decreased or prevented. Emission from road traffic is a plex system with an output that cannot be pletely measured. It is natural to analyze the emissions from a sample of vehicles under different driving conditions. The California Air Resources Board pointes out that congestionstop and go traffic significantly increases emissions. As an example, one report estimates that a 10mile trip, using an average 1987 automobile, results in running exhaust HC emission of 1grams at a speed of 55 mph but that HC emissions would be 7 grams at an average speed of 20 mph, typical of stopandgo conditions [10]. The relationship between emissions and speed can be seen in Table 1. Table 1 Emissions level in different speed [11,12] Speed (km/h) CO (g/km) CO2 (g/km) Fuel consumption (g/km) 10 310 130 20 240 96 30 200 79 40 170 65 50 150 55 60 145 48 70 138 43 80 130 40 100 110 50 With respect to air quality impacts, congestion pricing can be expected to improve air quality in two ways. The first impact es from the reduced level of congestion on the facility, pared with the level of congestion on the unpriced road. The second impact on emissions is due to the reduced number of vehicles on the road facilities. To the extent that higher prices succeed in reducing vehicle miles traveled, there will be fewer vehicles on the road. It is clear that reduced travel demand in peak periods reflects fewer and shorter trips being made and results in higher travel speeds during peak periods, with consequent reductions in vehicles emissions during peak periods. However, the bulk of daily travel occurring in offpeak periods may be negatively affected, as some peak travelers shift their time of travel to offpeak periods to avoid tolls. Overall beneficial impacts on air quality may thus be smaller than that suggested simply by peak period travel demand reductions. This reduction cannot be measured directly, but will have to be calculated from the information on traffic diversion, congestion reduction, and ridesharing increase. In the long term, congestion pricing could lead to increases in use of alternative travel modes for all daily trips, thus reducing total daily emissions. 4. Social justice Sustainable development has three widely agreed metagoals: sustainable e。