青藏公路多年冻土路段沿线植被及其变化

植被是维持青藏高原多年冻土地区生态系统平衡的关键因素。根据多年来观测调查资料,分析了青藏公路沿线植被的种类、类型及其特征,提出青藏公路沿线最普遍的三类植被是高寒草原、高寒草甸和高原沼泽群落,沿线植被生存环境极为脆弱,一旦破坏,很难恢复。通过样方数据揭示:除取土坑外,公路建设对植被的影响范围一般不超过公路界外50 m;受公路建设的干扰,公路两侧草原植被受到了一定程度的破坏,有明显的退化现象。

Vegetation and Changes Along Qinghai-Tibet Highway in Permafrost Region

The vegetation is the key factor to protect the ecosystem balance in permafrost region of Tibet plateau.On the basis of observation and survey for many years,the vegetation diversity,classification,and characteristics are analyzed.Alpine meadow,alpine steppe and alpine marsh are three general species along Qinghai-Tibet Highway.The fragile ecological environment along the highway is difficult to restoration after destroying.According to field survey,except for borrow pit,the effect distance of highway on vegetation is limit to 50 meters generally.Alpine meadow along the highway is destroyed at some degree and obviously degenerated.