森林土壤种子库与天然更新

Forest soil seed bank and natural regeneration.

论述了森林土壤种子库的特点 :(1)森林土壤种子库密度小于耕作土壤和草地 ,并且受森林类型和年龄的影响 ,变化幅度很大 ;(2 )森林土壤种子库的种类组成在森林的不同演替阶段 ,受其地上植被影响的程度不同 ;(3)森林土壤种子库的动态变化是周期性因数和随机性因数的结合 .并从土壤种子库的时间动态和空间分布角度 ,分析了土壤种子库对天然更新的影响 .森林土壤种子库是天然更新的物质基础 ,种子库的结构和功能影响天然更新的能力和方向 ,因此能影响土壤种子库格局变化的各种因子或措施 ,均能显著地促进或妨碍森林的天然更新 .根据森林土壤种子库的时空格局特点及影响更新的障碍因子 ,可以采用人工的辅助措施促进更新 .同时 ,对于森林土壤种子库的研究应着眼于应用干扰生态学的基本理论 ,以退化生态系统的重建和群落交错区的演替为主要内容 ,研究方法应以长期定位观测为宜 .

The characteristics of temporal dynamics and spatial distribution of forest soil seed bank and their effects on natural regeneration were reviewed in this paper.The density of the seed bank of forest soil,which is affected by the types and ages of forest,is lower than that of cultivated land and grassplot,and can vary widely.The extent to which the composition of forest soil seed bank is influenced by its counterpart plantation depends on the stages of succession.The dynamics of forest soil seed bank is the combined effect of periodical and random factors.It is suggested that forest soil seed bank is the material base of forest regeneration,and the configuration and function of forest soil seed bank would influence the ability and the direction of natural forest regeneration.According to the characteristics of forest soil seed bank and obstructive factors influencing regeneration,some artificial measures can be adopted to accelerate natural regeneration.Studies on the forest soil seed bank should focus on the application of basic theories of disturbed ecology,and regard the reconstruction of degenerative ecosystem and the succession of populations in the ecotone as the main contents to study.As for the research method,it is advisable to employ long-term and located observations.