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华北地区开发较早,森林资源遭受多次砍伐,毁坏殆尽,以致生态平衡失调。据河北省林业部门调查,太行山区1978年森林覆被率仅为11.62%,低于全国水平。但是,当我们踏上华北荒山秃岭时,常常看到一些乡土树种在茁壮地成长,有的占领了山坡,有的盘根曲枝嵌入崖石缝中。乡土树种在华北分布面积广,一般生长在海拔500—1600米的暖温带落叶阔叶林的林
In northern China, the development was earlier and the forest resources were repeatedly deforested and destroyed, resulting in ecological imbalance. According to a survey conducted by the forestry department of Hebei Province, the forest cover rate in the Taihang Mountains in 1978 was only 11.62%, lower than the national average. However, when we embark on the bald patches of barren hills in the north China, we often see some native species growing robustly, some occupying hillsides, and some packing twigs embedded in cliffs. Native species are widely distributed in North China, generally growing in warm temperate deciduous broad-leaved forest of 500-1600 m