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通过对吉林省三岔子林业局的野生穿龙薯蓣 (Dioscoreanipponica)年龄结构的调查 ,编制出了其野生种群的静态生命表。结果表明 :3～ 1 5年间 ,死亡率非常低。而 1 5年之后 ,特别是 2 5年之后的死亡率明显升高 ;年龄结构 ,在 30年之前 ,各龄级的株数基本符合正态分布规律 ,而 30年之后却偏离了这个规律 ,表现为各龄级的株数成直线减少 ;生命期望值在 30年之后明显增大。这充分表明了该地区穿龙薯蓣的种群正趋于衰退 ,该物种日趋濒危。
Through the investigation of the age structure of Dioscoreanipponica in Sanchazi Forestry Bureau of Jilin Province, the static life table of its wild population was compiled. The results show that: 3 ~ 15 years, the mortality rate is very low. After 15 years, especially after 25 years, the mortality rate has obviously increased. In the age structure, before 30 years, the number of strains in each age class basically accorded with the law of normal distribution, but after 30 years it deviated from this law, For each age class number of lines into a straight line to reduce; life expectancy increased significantly after 30 years. This fully shows that the population of Dioscorea zingiberensis in the area is declining and the species is becoming increasingly endangered.