毛乌素沙地飞播区植被动态变化研究

The aerial sowing vegetation dynamic changes in Mu Us sandy land

对毛乌素沙地不同飞播年限的4个播区进行调查研究,通过对盖度、重要值以及生活型的研究和分析,说明飞播对沙地退化植被有明显的改善作用。分析表明:飞播后飞播植被盖度随时间逐年增加,由14%增加到33%,说明飞播后植被得到良好的恢复;飞播后在不同的沙丘部位植被盖度各不相同,但是随着飞播年限的增加沙丘各部位的盖度相差不大;各飞播植物种的盖度和重要值随飞播年限的增加而变化,在飞播后的24年中呈现出不同的消长动态。飞播改良了沙地土壤的性质,使多年生和一年生的草本植物在群落中得以生长,随着飞播年限的增长,飞播群落的结构逐渐复杂,群落更趋于稳定。

The 4 aerial sowing areas in Mu Us sandy land in the different years were investigated. Aerial seeding had obviously improved the degraded sandy grassland showed by analysing the coverage and the importance values and the life form. The results showed： the coverage of aerial sowing vegetation increased year by year, from 14% to 33%. The change illuminated the vegetation of sandy land have a good resume after aerial sowing. The vegetation coverage of different positions of dune were different. But the vegetation coverage of the different positions were almost same some years later. The coverage and importance values of aerial sowing plant species changed with the years. Aerial sowing had modified the soil properties of the sandy land. The perennial herb and annual herb had settled in the community. As the years increasing, the community tended to be complex and become stable.