刺槐种群结构及生长动态研究

Study on Population Structure and Growth Dynamics of Robinia Pseudoacacia

研究了刺槐人工林的种群结构与生长动态．研究结果表明，样地内刺槐包括：2～10龄级的灌木层刺槐，17～26龄级的乔木层刺槐，缺少11～16龄级的从灌木向乔木过渡的部分；灌木层刺槐高度均小于4．50m，胸径均小于4．60cm，占总量的52．99％；乔木层刺槐高度均大于7．00m，胸径均大于8．13cm，占总量的47．01％．刺槐幼年时期的相对冠长、相对冠深均大于成年时期，表明刺槐幼年时期高生长、径向生长迅速、并且大于成年时期．种群内11～16龄级个体的缺失表明林下幼苗尚未发育成乔木，这在一定程度上增加了种群继续存在的风险．

The population structure and growth dynamics of Robinia Pseudoacacia plantations is studied. The results indicate that the population structure includes shrub layer with age stage of 2- 10, and arbor layer with age stage of 17-26,but the age stage of 11--16 is lost. The mean height and DBH of R. pseudoacacia in shrub layer are less than 4.50m and 4.60cm,but the proportion is about 52.99% of the total number of population. The mean height and DBH of R. pseudoacacia in arbor layer are larger than 7.00m and 8.13cm,but the proportion is about 47.01% of the total number of population. The relative canopy length and canopy width of seeding are larger than those older in arbor layer, which indicates that the seedling grows faster than the older. The scare of age stage of 11-16 displays that the seedling does not grow well, and becomes arbors,which increases the danger of population.