【摘要】 采用样地调查法对盐池县1991年以来不同时期的老封育区、新封育区和对照区进行半干旱沙地草场的植被特征及其生物量比较研究。结果表明:对沙化草地实施封育后,群落组成发生了规律性变化,随着封育年限的增加,封育区内的物种多样性逐渐增加;老封育区、新封育区和对照区在植物盖度、高度和生物量上差异并不显著,老封育区植被则以多年生草本为主;从3种措施植被的饲用价值来看,新封育区植被的饲用价值高于老封育区,表明长期封育不利于提高草场的放牧利用价值。更多还原

【Abstract】 The vegetation features and biomass of sandy rangeland in semi-arid area of Yanchi county were studied by means of plot investigation methods since 1991.Three treatments were respectively old closed land,new closed land and contrast land of different periods.The results showed that community composition had varied regularly after enclosure and the plant diversity of the grassland community had increased as the enclosing time extended;the vegetation coverage,mean height and biomass in the three areas have no significant differences.The community in old enclosed land was dominated by perennials.In the view of palatability of plant composition,community of new enclosed has higher palatability than old enclosed,which proves partly that long-term enclosure can not increase grazing values for rangeland in semi-arid area.更多还原