论文部分内容阅读
对受不同程度干扰的兴安落叶松原始林年龄结构的研究表明,一代林年龄结构动态的特点是初期种群密度增大,年龄变幅加大,后期因自然稀疏而年龄变幅减小。多代林是不同世代的一代林的斑块镶嵌,上层老年世代年龄变差小,中层的中年或成年世代变差大,下层幼年世代变差亦较小。白桦与落叶松在良好立地上混生时,初期因白桦定居早,其平均年龄比落叶松大5—15年,50—70年后,落叶松的平均年龄因部分白桦死去而变得较大。
The studies on the age structure of Larix principis-rupprechtii forest with different degrees of disturbance showed that the dynamics of the age structure of the first generation forests was characterized by the initial population density increasing, the age variation increasing, and the later period decreasing due to natural sparseness. Multi-generational forest is a patch mosaic of a generation of forests of different generations. The upper-aged generations have little variation in age, the middle-aged or adult generations have greatly deteriorated, and the lower generations have less variation in the younger generation. When birch and larch were mixed on a good site, the initial age of birch settled early, the average age was 5-15 years older than larch and 50-70 years later, the average age of larch became larger due to the death of part of Betula platyphylla.