中国森林资源1950-2003年结构变化分析

该文根据1950—2003年6次森林资源清查资料，对中国森林的结构变化进行了分析认为，经过50多年的培育、保护和利用，中国森林面积和蓄积有了大幅度提高，森林面积比建国初增加约111.74%，但蓄积增加仅约17.4%. 森林结构发生了巨大变化:人工林面积和蓄积比重逐渐提高，面积比重由1964年的4.49%提高到2003年的33.77%；天然林面积和蓄积比重明显下降，但天然林蓄积仍占森林蓄积的主体，到2003年仍占89.65%；针叶树面积和蓄积比重由原来的70%以上逐步降低，现在针阔比接近1∶1，而且优势树种结构也发生了较大变化，红松、樟子松和华山松等优质用材林几乎采伐殆尽；森林结构低龄化，单位面积蓄积量降低，可采资源减少；林种结构调整显著，防护林明显增加，用材林大幅度减少，两者的面积和蓄积已接近相等；防护林经营问题凸显，森林资源经营还处在向可持续经营不断接近过程中的森林多资源、多功能利用的初期；20世纪80年代后森林资源开始逐渐恢复，且势态良好，但到2003年森林资源质量仍未达到1962年水平. 因此，加强森林资源的培育，提高森林经营水平，加快林业建设以满足经济社会对森林的需求，依然任重道远. 

Change analysis on Chinese forest construction from year 1950 to 2003

Chinese forest construction was analyzed based on the data of six forest inventories from year 1950 to 2003, and a conclusion was drawn that both the forest area and volume had been increased greatly after more than 50 years of cultivation, protection and utilization, ie. forest area increased by 111.74% compared with that of the early stage of our country founding, while forest volume only increased by 17.4%. Also the forest construction varied enormously: the percentages of artificial forest area and volume had been increased gradually, among which the area percentage of artificial forests had been increased from 4.49% in 1964 to 33.77% in 2003; although the area and volume percentages of natural forests had been decreased obviously, the percentage of the natural forest volume still occupied most of the whole forest volume and it was 89.65% in 2003; the ratios of area and volume of coniferous forests had been decreased gradually from that above 70%. Now the ratio of the coniferous to the broadleaved is almost 1∶1, and the construction of dominant trees has changed extremly: most commercial forests that have good quality, such as Korean pine, Mongolian pine, Armand pine, etc, have been almost cut over; forest construction has changed to younger, per unit volume has decreased, and little forest resources can be cut and used; the structure of forest function types has been adjusted greatly, ie economic and protective forests have been increased obviously, while commercial forests have been decreased enormously, and they almost have equal area and volume. The management problems have been brought out and it is showed that forest management is on the initial stage of forest utilization based on multi_resources and multi_function towarding sustainable management. After 1980s, forest resources have begun to be restored and have a good tendency, but the quality of forest resources in 2003 has not reached the level of 1962 So, the important and heavy task is still there to improve forest cultivation and management in order to meet the economic society’s need.