The Sprawl Of Metropolitan Areas And The Conserrvation Of Land Resources By Land Trust Organizations In The United States

The American metropolitan areas,which were formed in the early 20 th century,refer to the huge complexes composed of the central cities and their surrounding suburbs.They each covers a large area and has a large population.Due to the promotion of suburbanization in the United States,the population density in the surrounding areas is relatively low.Since the 1950 s,American metropolitan areas have shown an obvious trend of low density sprawl,resulting in the loss of a large number of land resources,causing public concern.In response to the threat of metropolitan sprawl,the United States land conservation movement was formally launched at all levels of governments and civil environmental groups.Among these forces,the American land trusts are the backbone of the private land protection.An American land trust is a kind of private,non-profit public organizations,through direct purchase and holding of land,accepting donations,using the conservation easement,and other comprehensive protection methods,obtained the excellent achievements of land conservation.For the United States and the world land protection,they provide a new train of thought and experience.The main body of this dissertation consists of two main parts,namely the background introduction of metropolitan sprawl and thematic study of American land trusts,which can be divided into seven chapters.Of these,the first part contains chapters 1 to 3,and the second part contains chapters 4 to 7.In the first part,the first chapter introduces the formation and development of metropolitan areas in the United States.The second chapter introduces the spread of the metropolitan areas and the threat posed on the various types of land resources,including natural open space,wildlife habitats and farmland.With data analysis,this chapter forms the intuitive picture,highlights the spread of the metropolitan areas which cause the serious threat of land resources,and in turn leading to the rise of the American land conservation movement;The third chapter introduces the land protection movement,explores in the form of an overview of land protection activities of federal,state and local governments,with the advocacy organizations,the private and the other nonprofit groups.The second part is the main part of this dissertation,focusing on the land trust movement in the United States under the background of the spread of metropolitan areas and the loss of land resources.The fourth chapter is a overall introduction to the Land trust organizations in the United States,including their brief history,their common protection methods and protection achievements.Chapter five and chapter six,respectively,in the form of case study,selected The Nature Conservancy which is professional in the nature conservation,especially wildlife habitat,and the American Farmland Trust which is professional to protect agricultural land.These two chapters launch a detailed research,mainly from both the protection methods of diversification,which can summarize the experience of the exploration of its development.Finally,the seventh chapter is the evaluation of the land trust organizations in the United States.The author concludes the successful experience and shortcomings of the Land trust organizations in the United States by summarizing the contents mentioned above,and tries to provide references for the land resource protection in China.