围栏封育在藏北高寒退化草地恢复中的效果研究

通过对西藏安多典型退化草地围栏,研究围栏对植被特征、地下生物量、地下种子库以及多样性等方面的影响。结果表明:经过围栏封育后草地植物高度、盖度、产量均有不同程度的提高。植物多样性有所增加,植被优势种差异较为显著。植物群落地下生物量变化幅度较大,经过围栏草地0～10 cm地下生物量增加明显。土壤种子库测定表明,围栏实验地种子总数明显高于围栏外,且增加的种子数主要分布在0～5 cm的土层中。

Effect of Closed Fencing on the Restoration of Deteriorated Alpine Grasslands in Northern Tibet Plateau

With a case study on the closed fencing of the typical deteriorated grassland in Ando of Tibet,the effect of closed fencing on the vegetation characteristics,underground biomass,underground seed bank and diversity was explored.As indicated by the results,the vegetation height,coverage and grass yield all improved to different extents after the closed fencing,furthermore,plants diversity increased slightly and there were significant differences among the dominant species.Besides that,great changes had taken place in underground biomass of plant communities.It is obviouly evident that biomass of 0-10 cm ascended dramatically after enclosure.In addition,soil seed bank was also studied and determined.It demonstrated that the number of seeds inside of the enclosure outweighed the outside of fence and the increasing seeds were mainly distributed within 0-5 cm soil layer.