利用Zipf定律与分形理论对我国森林资源规模分布进行了定量分析。结果表明:无论是以有林地面积还是以活立木蓄积量为指标,我国森林资源的规模分布均符合Zipf定律,通过Zipf定律把握森林资源规模的分布是可行的。其中有林地规模分布的无标度区说明我国有林地资源分布具有良好的空间结构;蓄积量规模分布的双分形特征说明蓄积量资源分布的结构仍有进一步优化的空间。
According to the data of 6th national forest inventory, we analyzed the forest resource size distribution by timberland area and forest volume. The log-log plots showed that the forest resource size of China was inconformity with Zipf's law, and it was a feasible way to study the ranking structure of forest resource quantitatively by Zipf's law. Through the research on .timberland area, the plot shows that 26 of 31 units were located in the scaleless band and the Zipf dimension could be known by the fitting equation. The conclusion was that the timberland area size distribution had a fine ordering structure that can be drawn. However, the log-log plot of volume size in China demonstrated that the distribution had the character of double fraetal, which means there were two scaleless bands on the plot. Also it could be deemed as that there exist two subsystems in volume size system of China. And the character of double fraetal illustrated that the ordering structure of volume size in China need to be enhanced. Scaleless band Ⅰ of the volume size system included five units and the Zipf dimension, while 20 units located in scaleless band Ⅱ and the Zipf dimension. The above results interpret that the structural difference of scaleless band Ⅰ is much less than that in scaleless band Ⅱ. Perhaps the reason was that the effect of afforestation was on the primary stage. We could get instant outcome on the ordering structure of timberland area compared with the forest volume. It also reminds us of that enhancing the quality of forest is a long-term mission.