Zhao+Yanli

【Abstract】This thesis researches into the problems in transportation system and challenges of urban sustainable mobility of Atlanta. MARTA has not been able to solve Atlantas problems in traffic congestion and air pollution. The reasons for the failure are multifold. Most importantly， Atlanta is characterized by an extreme low density in 0urban. Such type of urban spatial structure is incompatible with mass transit which requires a sizable transit market share. It seems that failure MARTA is unquestionable. Then the more important question is why does it fail？ This article analysis it from factors of population， government， transport network.

【Key words】Sustainable Transport； MARTA System； Decentralized distribution

1. Decentralized distribution of population

There are deficiencies in operating conditions of bus system caused by Atlanta citys low-density expansion. First， the recent development model of the city of Atlanta can be described as the rapid growth of low-density dispersion. With the rise of large and small Sun Belt cities， Atlanta is developing on a large scale. It attracted a large number of enterprises and households migrated to the area. From 1960 to 1990， the population grew by 142 percent in Atlanta. The city is the nation's fastest growing cities.

However， population growth and its land consumption are disproportionate. By 1990， the region's population increased by only 13%， but the regional land area has increased by 50%. This means that although the Atlanta metropolitan area is developing rapidly， its population density is still at very low levels. Meanwhile， most of the population grew in the suburbs of Atlanta. In 1960 the city center population accounted for 47.9 percent of the region's total population， but by 1970 that percentage had dropped to 35.7%. Rapid population growth means corresponding growth in employment. But Atlanta employment centers are geographically far away from most of the city center. Although the proportion of the population density and public transportation has no direct connection， practices show that the lower the population density， the more difficult the operation of public transport systems is. Jobs and population are dispersed across the metropolitan area. Atlanta low population density and the distribution of employment made it difficult to develop effective public transportation system. Private cars would become the only effective urban transport. In contrast， Shanghai is a single-center city with very high population density. Such high density is difficult to support the development and use of private cars， while public transport is efficient. Decentralized distribution of the population is an important reason for Atlanta's mass transit system failure.endprint

2. Uncoordinated planning system in transportation

Atlanta city's construction began 30 years ago in coping with the growth of population. The city started to construct roads and residential in suburbs without a long-term planning. Until the city has been developing for many years in disorder， did it began to make plans.

Atlanta has no effective regulations to increase population density. Land Use Act did not protect the land resources effectively either. For fear of the establishment of the urban development boundary could increase land and housing prices and hinder the development of urban economic， Atlanta and no Urban Growth Boundary. Still there are no policies to protect of green to limit the supply of land so as to control the spread of the city.

For the entire region， the Atlanta metropolitan area does not have a regional authority to develop a regional plan based on the common interests. Tax Share in Atlanta metropolitan area also caused imbalance in development. Although the Atlanta area is a complete economic entity， there is no one entity may be responsible for the overall future development. Local governments often take decisions of the region which contrary to the common interest. Georgia law gives states little power at the local government to implement government plans.

3. Conclusion

The bus system plays a important role in improving urban transport and control of environmental pollution. But the government's policy orientation is to support construction of highway than tilted to the bus system. Factors include decentralized distribution of population， lack of support from government， uncoordinated planning system in transportation， a car-dominated transportation network and MARTA's own defects together contributed the failure of bus system. The failure case in sustainable transport of MARTA system indicates that a full understanding of the region's urban spatial structure and citys own condition is necessary for an ecological city in developing an appropriate transportation strategy.

Work cited

【1】Lao Y， Liu L.“Performance evaluation of bus lines with data envelopment analysis and geographic information systems.” Comput Environ Urban Syst （2009）：247–255

【2】宋彥，丁成日. 交通政策与土地利用脱节的案例——析美国亚特兰大的MART公 交系统[J]. 城市发展研究，2005，54-59.

【3】张生瑞. 公路交通可持续发展系统分析与评价[D].长安大学，2002.endprint