准格尔黄土丘陵沟壑区杜松疏林特征分析

Characteristics of Juniperus rigida Open Forest in Junger Loess Hill-gully Region

对内蒙古准格尔黄土丘陵沟壑区天然杜松疏林进行了林分胸径、株高、密度和群落结构等的调查.结果表明:发育良好的杜松疏林具有明显的乔木层、灌木层和草本层,如杜松-虎榛子-日阴菅群落、杜松-黄刺玫-日阴菅群落、杜松-黄刺玫-黄囊苔群落;若干扰进一步减弱,它们会演替为辽东栎+杜松或油松+杜松群落;若干扰加强,杜松疏林会逆向演替为灌丛或草原,甚至为裸沟坡地.杜松疏林有高的物种丰富度,但生境脆弱,且林分平均胸径、平均高、密度均较小,故不适合作为用材林,应作为水土保持林和种源林加以保护利用更为合理.

The breast diameter,height,plant number and community structure of Juniperus rigida open forest,distributed in Junger loess hill-gully region of Inner Mongolia were investigated by quadrat method.The result shows that J.rigida open forest has obvious tree,shrub and herb layers,such as the Ass.J.rigida-Ostryopsis davidiana-Carex pediformis,Ass.J.rigida-Rosa xanthina-C.pediformis,Ass.J.rigida-R.xanthina-C.korshinskyi.If the habitat keeps stable continuously,it will be replaced by Ass.Quercus liaotungensis＋J.rigida or Ass.Pinus tabulaeformis＋J.rigida.If the habitat is disturbed continuously,it will be replaced by shrub communities or grassland communities,even bare slope.J.rigida open forest has highly species richness,but its habitat is vulnerable,the stand density is low,the stand average breast diameter and average height is smaller,so J.rigida open forest is not suitable for timber forest,which should been protected as soil and water conservation forest and provenance forest.