Research On Dynamic Evolution And The Driving Mechanism Of Cultivated Land Fragmentation Degree In Metropolitan Area

The creation of giant urban like Beijing was resulted from the continuous high pace of economic development, industrialization and urbanization in China for the past 30 over years. The huge urban scales, extension of the city and diverse population have a great impact on the size of usable farm land around the city. The succession of farmland, meanwhile, showed obviously in metropolitan area. At present, extending the areas of capital farmland is the key effective measure. However, there are many construction sites, parks and wasted land in the planned area of Beijing city and the fragmented land areas have resulted low productivity in farming and restricted the use of machinery for larger-scale farming. So, it is necessary to have police guidance to promoting Land Consolidation for extending high grade farmland.This study is about the fragmented farmland in Daxing district of Beijing city. The analysis of the farmland in Daxing district is based on the literatures from both international and China and investigating the various influencing factors that contributing to the quality of land use. The analysis of spot density and landscape fragmentation in the 3 location is based on the theories from landscape ecology and using the indicators from the spot and landscape standard and applied mathematics and GIS technology. The result indicates that:(1) Using the indicators from the spot and landscape standard for analizing the fragmentation of farmland, such as CA, PD, NP, AREA-MN, COHESION, SPLIT and DIVISION. Amount of farmland was reduced in Daxing from 2000 to 2004, the fragmentation degree was gradually deteriorated; but from 2004 to 2008, this situation has improved. The fragmentation degree of farmland on both sides of corridor showed the regular change with the different distances to corridor.(2) The cognition and requirement of the farmland function to local government, different social strata have been changing with the rapid economic development and the farmland fragmentation degree was improving gradually. The influencing driving mechanism of farmland fragmentation is the driving-process of output-income driving force and industrial structure driving force. It indicates that the key driving force for the change of farmland fragmentation in metropolitan area is the improvement of output-income level, the optimization of industrial structure and the agricultural structural adjustment.