多伦县沙质草原植被的变化趋势分析

在多伦县 1984年草原普查资料的基础上 ,2 0 0 1年又在 2 8个样点上进行了较详尽的野外考察 ,比较了相隔 17a的草原植被变化。结果表明 :潜在沙漠化土地的面积占有相当大的比例 ;中度、重度退化的比例从 5 0 %又有了扩大的趋势 ,这说明多伦县沙漠化的潜在隐患十分严重 ;近年来实施的草原保护起到一定的作用 ,表现在一些退化的样点有了恢复 ,最典型的例子就是黑山嘴乡胜利村 (沙质栗钙土 ,冷蒿 寸草苔 杂类草 ,重度退化 )沙质草原中的冷蒿群落在封育保护下已经恢复为以大针茅为建群种的群落 ;而不合理的利用 ,继续使一些样点上的群落退化。总的趋势仍是局部好转 ,总体恶化 ;挖掘和开垦则具有剧烈性的破坏作用 ,植被表面形成的“破口”在风蚀、水蚀的作用下 ,沙漠化的进程将会迅速发展

Analysis on the Changing Tendency of Sandy Grassland Vegetation in DuoLun County, Inner Mongolia

In 2001 we made an on the spot thorough investigation into the 28 sample spots on grassland of Duolun County. These sample spots had ever been investigated in 1984. Comparison of grassland vegetation clearly shows that: potential desertified land accounts for the majority of the total area; the proportion of medium degenerated and seriously degenerated lands has enlarged to be more than 50 percent of the desertification area. But there are still obvious effects of closing grassland. Vegetation recovered in some degraded spots. The most typical case is Sheng Li village, where the Artemisia frigida community (sandy chestnut soil, Artemisia frigida Cares duriussula rank grass, seriously degenerated) in sandy grassland has recovered to community dominated by Stipa glandis. Community in many sample spots is still degenerating under irrational exploitation. Excavation and reclamation are most destructive. Under the action of wind erosion and water erosion, the gap developed and desertification would be faster and faster.