秦岭冷杉和巴山冷杉种群年龄结构及动态的比较分析

Comparisons of Age Structure and Population Dynamics of Abies chensiensis and Abies fargesii

在秦岭林区对不同生境条件下濒危种秦岭冷杉(Abies chensiensis)和广布种巴山冷杉(Abies fargesii)种群的年龄结构、生命表、存活曲线以及时间序列预测进行了比较分析。结果表明:秦岭冷杉在各个坡向上幼龄林林木株数均明显小于巴山冷杉。在各个坡向上,秦岭冷杉均呈衰退型,而巴山冷杉均呈稳定型。坡向对秦岭冷杉种群存活曲线的影响比巴山冷杉的影响大。在未来的20、40及60 a,秦岭冷杉种群Ⅱ、Ⅲ龄级的种群表现为先增后减的不稳定趋势,而Ⅳ龄级以后的种群表现为小幅度的增加趋势。巴山冷杉种群各龄级株数在未来的20、40及60 a均呈明显的增加态势。最后,给出了对不同生境的秦岭冷杉应采取的具体管理措施。

An experiment was conducted to study the age structure, life table, survival curve, and time series prediction of the endangered species Abies chensiensis and the widespread species Abies fargesii in different habitats in Mt. Qinling, Shanxi Province. Results showed that young stands of A. chensiensis on different slope aspects presented a decline in population size, but young stands of A. fargesii were stable in population size. And the number of young trees of A. chensiensis was obviously lower than that of A. fargesii. Slope aspect had a stronger influence on the survival curve of A. chensiensis than on A. fargesii. Time series prediction indicated that there would be two different development tendencies for A. fargesii population in 20, 40 and 60 years in the future, namely the tree number of A. fargesii population for the second and the third age classes showed an unstable tendency of early increase and later decrease, while the population for the fourth age class exhibited a slightly increasing tendency. Tile tree number ofA. fargesii population for all age classes showed an obviously increasing tendency in 20, 40 and 60 years in the future. The concrete countermeasures for the management of A. fargesii were given according to different habitats.