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河北省张家口坝上地区,系内蒙古高原的南缘,气候寒冷、干旱,土壤瘠薄,在历史上为蒙古族游牧区,林木极少。解放后,虽然营造了大面积青杨人工林,但在山地阳坡及干旱丘陵成活率很低,而且成活的大部分均已成为“小老树”,逐年干枯死亡。为给石质山地阳坡引进适宜树种,我场1974年从内蒙引进樟子松,1978年以后又陆续引种。经多年观察,樟子松生长良好,是目前石质山地阳坡生长表现最好的树种。一、引种地概况试验地设在坝头山地,位于北纬41°,东经114°13′,海拔高1,450米。年平均气温2.1℃,极端最高气温35.1℃,极端最低气温-34.4℃;无霜期(?)0天。年降雨量350—400毫米,年蒸发量1,900—2,100毫米。全年大风(≥17米/秒)
Dam area in Zhangjiakou, Hebei Province, is the southern margin of the Inner Mongolia Plateau. The climate is cold and arid with infertile soils. It is a nomadic area in the history of Mongolia, with few trees. After the liberation, although a large area of Populus deltoides plantation was created, the survival rate in the mountainous sunny slopes and dry hills is very low. Most of the surviving ones have become “small old trees,” and have died each year. In order to introduce the suitable tree species for the mountain slope of stony hill, my field introduced Pinus sylvestris from Inner Mongolia in 1974, and introduced one after another from 1978. After years of observation, Pinus sylvestris grows well, which is the best growing tree species in the sunny slope of stony mountainous area. I. INTRODUCTION INTRODUCTION The experimental site is located in the headland of the dam, 41 ° north latitude, 114 ° 13 ’east longitude and 1,450 meters above sea level. The annual average temperature of 2.1 ℃, extreme maximum temperature of 35.1 ℃, extreme minimum temperature of -34.4 ℃; frost-free period (?) 0 days. Annual rainfall of 350-400 mm, the annual evaporation of 1,900-2,100 mm. Annual gale (≥17 m / s)