汉中市耕地资源动态变化及驱动力研究

根据汉中市1978～1998年耕地数据,研究汉中市耕地面积变化,以及各区县耕地利用动态度和相对变化率;结合汉中市20年来社会各经济因素,采用主成分分析法,探讨影响汉中市耕地数量变化的驱动力因子。结果表明:1978～1998年,汉中市耕地面积共减少4.22万hm2,累计减少率为14.72%;全市人均耕地面积净减少0.019 7 hm2,累计减少率为22.34%。各区县耕地利用动态度均为负值,动态度最大和最小的分别为南郑县和留坝县;耕地利用相对变化率均大于0,留坝县耕地面积减少率为全市最大。耕地变化驱动力因子主要为社会经济发展、人口、农业技术进步、粮食安全保障和畜牧业生产。

Dynamic Change of Cultivated Lands and Its Driving Forces in Hanzhong City

Based on the farmland data of Hanzhong City from 1978 to 1998,the changes of cultivated area as well as the land use dynamics and relative change rate were studied.The driving factors of cultivated land changes in Hanzhong City were analyzed with the socio-economic factors in the last 20 years using the method of PCA(principal component analysis).As indicated by the results,during 1978-1998,The area of cultivated land has reduced by 4.22×104 hm2,and the total declining rate was 14.72%.The per capita area of cultivated land has reduced by 0.019 7 hm2,and the total declining rate was 22.34%.The cultivated land use dynamic degree in all counties was negative,the maximum and minimum value of cultivated land use dynamic degree was found in Nanzheng County and Liuba County,respectively.The relative change rate of cultivated land use was positive,and the largest declining rate of cultivated land area was in Liuba County.The principal driving factors of cultivated land change were socio-economic development,demographic factor,technological advances in agriculture,food security and livestock production.