摘要: |
本文从分形概念入手,介绍自然界(水系、云、雪、树木)普遍存在分形特征。继而用偏差法求解中国湖泊分布的分形特征。并对其进行地理意义的解释,为湖泊信息分类和湖泊数据库建设服务。 |
关键词: 湖泊 分形特征 偏差法 |
DOI:10.18307/1997.0314 |
分类号: |
基金项目:国家自然科学基金资助项目(编号:49271057) |
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The fractal feature of lake distribution in China |
Zhao Hong1, Zhao An2
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1.Nanjing Institute of Geography & Limnology, CAS, Nanjing 210008;2.Nanjing University, Nanjing 210008
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Abstract: |
Waternet, cloud, snow and forest, etc have fractal features of nature. As compared with pure mathematical conception of Fractal, the fractal features in nature differs in two:1) nature fractal features will be manifest only in certain scales and ranges. 2) there does not exist such a pure conception, that it must be processed by mathematics statistical method. The fractal features of geographical phenomenon in as well as the progress in the research on seacoast, river, topography, town distribution and so on are discussed. Varigram is introduced to compute the fractal feature of Chinese lake distribution. The Chinese Lake Database, in which lakes of over 10 squared kilometres in China are included, is chosen, and the whole country group and the Qinghai-Xizang Pleteau group are selected. The distances of each two lake centres are computed, then 100 groups are divided into according to the distance. In each distance group, the average lake area variance is computed, the log-log plots are drawn. The computed slopes of recursive plot in the two groups provide information on the fractal dimensions of the two lake groups. The results show that the fractal dimension for the whole country group is 2.564 with a regression coefficient of 0.634, while the dimension for the Qinghai-Tibet Pleteau group is 2.359 with a regression coefficient of 0.759. In the end, the geographic explanation on the fractal character of Chinese lakes is given, which can be used in lake classification and lake database establishment in China. |
Key words: Lakes in China fractal feature varigram |