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综合采集20世纪前、中期全国多种宝贵的土地利用数据, 特别是早期的一些土地利用资料, 利用聚类分析方法将中国大陆部分省区按土地利用变化差异分为7个区: 东北区、华北区、西北及黄土高原区、东南沿海区、西南区、青藏高原区和蒙新区, 分别对各区的农林土地利用, 即耕地、林地的时空变化进行了分析. 结果表明, 大部分地区耕地面积有较为明显的增加趋势, 20世纪50~60年代, 各区的耕地面积增加较多, 最大年增长率为2.63%, 区域差异较大; 20世纪前、中期林地面积以1949年为界, 此前总体下降、此后有一定的增加趋势. 有林地面积也呈现比较明显的区域差别, 70年代后期多数地区林地面积减小严重. 20世纪前、中期土地利用变化是自然和社会经济条件综合作用的结果, 但是人口增加、粮食生产、政府政策变更等社会经济因素的影响更大, 自然灾害也是土地利用变化的重要因素.
This paper comprehensively collected many valuable land use data of the whole country before and during the 20th century, especially some early land use data. According to the cluster analysis method, some provinces in mainland China were divided into seven regions according to the difference of land use change: Northeast China, North China, Northwest and Loess Plateau, southeastern coast, southwestern region, Qinghai-Tibet Plateau and Mongolia were used to analyze the land use of agriculture and forestry in each area, ie the temporal and spatial changes of arable land and forest land.The results showed that in most areas, There was a clear trend of increase. From the 1950s to the 1960s, the cultivated land area increased greatly in all districts, with the maximum annual growth rate of 2.63% and a large regional difference. In the early and mid-20th century, the area of forestland was bounded by 1949, The area of forest land also showed obvious regional differences, the area of forestland decreased seriously in most of the area in the late 1970s.The change of land use in the first and mid-20th century was the result of the combined effect of natural and socio-economic conditions, However, the impact of socio-economic factors such as population growth, food production and changes in government policies is even greater, and natural disasters are also land Make use of the important elements of change.