| In this paper, a concept of urban agro ecological security and its evaluation indicator system are put forward, and comprehensive evaluation for urban agriculture ecological security in Xi'an City has been carried out by applying the entropy value method, obstacle degree analysis model and GIS spatial analysis technique. The result shown that: The safe index of urban agro ecological security has increased from 0.44 in 2002 to 0.68 in 2011, the urban agro ecological security conditions were improved obviously. The urbanization have large negative influence to the sustainable ability and system stability of urban agricultural resources, while more positive influence on output sustainable increase and development ensure ability. In recent ten years, the average obstacle degree of the key factors which impeded the improvement of urban agro ecological security were 12.47%, 7.05% and 4.97% respectively in the years of 2003, 2006, and 2011, which shown that the obstacle degree has gradually decreased in Xi'an City. The ecological security index in Xi′an Region was S≤0.15 in Lianhu, Beilin, and Xincheng district, 0.15<S≤0.27 was in Lantian County. S＞0.35 was in Chang’an and Yanliang District. 0.27<S≤0.35 was in the rest of districts. This indicated the significant spatial differentiation due to the difference of agricultural production condition, the convenience degree of traffic, and linking degree to urban economic in each distric
t of Xi'an City. |