关键词: 单位叶面积滞尘量, 单位叶面积滞尘量

Abstract: The paper in order to study the urban areas, the use of mathematical statistics and the combination of the gis spatial analysis methods, reveals the Langfang City rural-urban fringe areas food security changes in production patterns. The results show that: ① 1996 years -2006 years the township urban food security index was fluctuating trend, that is stable (in 1996 -1999) → diminishing (in 2000 -2004) → slow rise (in 2005 -2006 ) the trend of the maximum coefficient of 2.23 for Kyushu in 1996, is the smallest value in 2003 for 0.50 Chou Zhuang. ②Grain yield is divided into "quantity" and "quality" factor, because different stages of "quantity" and "quality" factors on grain yield in different degrees, resulting in 1996 -2,006 on Food Security in the pattern of center of gravity, from "outside" to "within the" offset of 2.39km.③Cobb-Douglas production function showed that the sown area of grain and the impact of effective irrigation area of food production capacity is an important factor, Urban fringe areas of arable land loss of reserve status of serious shortage of arable land, the future should strengthen the intensive use of arable land to explore the potential of grain production in order to ensure regional food security, promote socio-economic harmful development.