西藏退化天然草地改良效果研究

目的]选择拉萨市纯牧业当雄县重度退化天然草地进行补播和围栏封育效果研究，为西藏退化草地的改良与治理提供科学的依据。方法]在补播围封点和实施围栏封育的退化沼泽化草甸草地，均以围栏外为对照，进行围栏封育区、补播区和对照区植物群落盖度、密度、高度、物种数以及地上生物量的测定与比较。结果]结果表明，在补播围栏封育区，除毒草之外的其他草种高度都有所增加，植被总盖度、密度、地上生物量较补播之前分别增加33．00％，101．42％，16．10％（P〈0．05）；退化沼泽化草句草地实施围栏封育的藏嵩草产草量明显高于围栏外对照，围栏内8月份出现藏嵩草最高产量，围栏封育最高产草量可达围栏外自由放牧对照区最高产草量的4—5倍，围栏内最低产量也是围栏外自由放牧区最高产量的4倍。结论]补播和围栏封育见效快、效果好、简便易行，对于西藏特殊环境条件下的退化天然草地恢复改良最容易实施，值得推广应用。

Research on the Improvement of Degraded Natural Grassland in Tibet

Objective] The effect of grass re-sowing and fencing for grass growth on the improvement of severely degraded grassland in Dangxong County of Lasa City in Tibet was studied for the provision of scientific basis of the improvement and management of degraded grassland.Method] In the grass re-sowing and fencing area of degraded swamp meadow,the area outside the area was taken as the control,and the covering degree,density,height,number of species and aerial biomass of the community in enclosed fencing,grass ...