亚高山针叶林自然恢复过程中的物种多样性变化

Dynamics of Species Diversity in Natural Restoration Process of Subalpine Coniferous Forest

在亚高山针叶林的恢复与重建中,物种多样性的变化与配置具有极其重要的作用。本研究以自然恢复过程中不同演替阶段的群落为对象,采用空间代替时间的群落学调查方法,对亚高山针叶林自然恢复过程中不同演替阶段群落物种多样性变化进行了对比研究。结果表明:糙野青茅(Deyeuxia scabrescens)、高山柳(Salix paraqple-sia)、白桦(Betula platyphylla)、紫果云杉和桦木(Betulaspp.)混交、岷江冷杉(Abies faxoniana)、紫果云杉(Picea purpurea)和粗枝云杉(P.asperata)群落的物种丰富度(S)分别为46、54、69、38、61、38和26,Shannon-Wienner指数(H)分别为2.42(±0.10)、2.71(±0.06)、2.93(±0.06)、2.59(±0.11)、1.83(±0.43)、1.81(±0.32)和1.75(±0.24),均优丰多样性指数(Z)分别为17.39(±1.81)22.52(±1.09)、23.76(±2.09)、18.13(±1.74)、7.05(±1.75)、6.69(±1.01)和5.26(±2.30)。②在植被恢复的过程中,物种的丰富度、多样性指数和均匀性都在不断波动,其变化趋势是"低-高-低",随着演替的进行,草本逐渐被灌木替代,灌木又逐渐被乔木替代,到顶极时期,群落的物种多样性虽然较少,但结构更完整。③在生态恢复的相邻阶段,群落间的物种相似性高、群落结构类似、共有物种也较多。

Species diversity development and collocation play an important role in the process of restoration and reestablishment of subalpine coniferous forest. The survey on 7 communities of gramineous community （dominated by Deyeuxia scabrescens）, willow shrub （dominated by Salix paraqplesia）, birch forest （dominated by Betula platyphylla）, needle and broadleaf mixed forest （dominated by Betula spp. and Picea purpurea）, fir forest （dominated by Abies faxoniana）, spruce forest （dominated by P. purpurea） and spruce plantation （dominated by P. asperata）, was conducted in order to study the species diversity, community coefficient and community similarity coefficient of different natural restoration stages in subalpine coniferous zone. The results indicated that： ①The species abundance （S） were 46, 54, 69, 38, 61, 38 and 26, the Shannon-Wienner diversity index （H） were 2.42 （±0.10）, 2.71 （±0.06）, 2.93 （±0.06）, 2.59 （±0.11）, 1.83 （±0.43）, 1.81 （±0.32） and 1.75 （±0.24）, the integrated diversity index （Z） was 17.39 （±1.81）,22.52 （±1.09）, 23.76 （±2.09）, 18.13 （±1.74）, 7.05 （±1.75）, 6.69 （±1.01） and 5.26 （±2.30） in gramineous community, willow shrub, birch forest, needle and broad-leaf mixed forest, fir forest, spruce forest and spruce plantation, respectively. ②In the restoration process, the species abundance, diversity and evenness of 7 types communities fluctuated with the natural restoration, and the development trend was ＂low-high-low＂. Following the process of natural restoration, lots of the herb were replaced by shrubs, and then the shrubs were replaced by trees. The structure of climax community was were perfect compared to the earlier restoration communities although its species were lower. ③The neighbor communities in the process of restoration had the higher similarity, and the communities of similar canopy structure had more common species.