围栏内禁牧与轻牧对高寒草原群落的影响

Influence of fencing and light grazing on enclosed alpine steppes in the Qinghai lake area

以青海湖北岸青海省三角城种羊场的天然高寒草原为研究对象,对围栏内全年禁牧与轻牧下草地群落及生物量变化进行了比较研究。结果表明:围栏内全年禁牧虽然提高了草地的初级生产力,但却使草地群落的均匀度、物种多样性及禾草在草群中所占比例下降;而围栏内轻牧,牧压虽轻,但仍没有避开草地春季返青的危机期,并且由于羊群对草地枯落物的啃食以及严重的风蚀,草地退化严重,使草地生态系统的营养物质循环受阻。所以应该优化青海湖区草地生态系统的放牧管理制度,实现高寒草地畜牧业的可持续发展。

A study was conducted at the Sanjiao city sheep breeding grassland area of Qinghai province, which was located on natural alpine grassland of the north bank of Qinghai Lake. The changes of grassland population and biomass of fencing and light grazing were compared. The results showed that a two-successive-year fencing increased primary production, but it decreased species diversity, evenness and the percentage of grasses. Lightly grazed grassland in enclosure has been in a crisis stage of plant germination....