为了揭示不同区域土地利用变化之间的空间联系,借鉴经济学中的区域优势理论,提出了区域土地利用优势的概念及其度量方法:进而利用该方法以及国土资源调查数据和统计数据.分析了中国1996-2003年间土地利用的分区优势以及分区优势的演变。研究发现上海、天津、北京、江苏、浙江、山东、广东等建设用地具有明显优势的地区,建设用地优势指数快速上升.上升幅度在0.17以上,使得这些省区建设用地的优势越发明显.而农地优势有所下降:河北、福建、海南、吉林等原本就具有农地利用优势的区域,农地优势上升较大,而广西、云南、宁夏、甘肃、新疆、内蒙等省区农地优势则略有上升。同时河南、安徽、湖南、黑龙江、四川林草地优势明显上升。研究结果表明,中国土地利用的分区优势在其演化过程中存在高端极化机制、梯度外推机制和生态阻拦机制。这三大机制在全国尺度上不仅主导中国土地利用分区优势的演化过程.同时也主导中国近期土地利用格局的变化。
Land use changes in different regions have profound spatial connections. In order to reveal the spatial linkage among land use changes of various provinces in China, the conception of land use advantage index is defined firstly referring to regional advantage theoryin economics, and a method(Di=Bi×Si/Bmi×Smi)is established to measure the index. Based onthe index, land use data, and production value published in statistical yearbook, landuse advantage of different regions in China and its evolution between 1996 and 2003 are analyzed. The results show that the provinces with remarkable advantage in built-up land, including Shanghai, Tianjin, Beijing, Jiangsu, Zhejiang, Shandong and Guangdong, strengthen their advantage in built-up land to an extent higher than the national average. Meanwhile, the advantage in agriculture land decreases in most of those provinces. The provinces with relative advantage in agriculture land, including Hebei, Fujian, Hainan and Jilin, strengthen their advantage in agriculture land to an extent exceeding Guangxi, Yunnan, Ningxia, Gansu, Xinjiang and Inner Mongolia. Advantage index increases in forestland or grassland in Henan, Anhui, Hunan, Heilongiiang and Sichuan. Those results imply that there are three evolvement mechanisms in the evolution process of land use advantage. They are polarization mechanism, gradient extrapolation mechanism and ecological blocking mechanism. By exploring the results of the existing researches on land use changes in China, it is further confirmed that the three mechanisms, at the national scale, not only dominate the evolution process of regional land use advantages in China, but also dominate the changes of land use pattern in China.