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一、前言樟子松(Pinus sylvestris L.var.mongolica Litvin.)常绿乔木,主要分布于大兴安岭北部、呼伦贝尔盟草原的沙丘上。树高常达15～20m,最高30m,最大胸径1.0m 左右,寿命高达200年。树干通直,材质良好。耐寒性强,能忍受-40～-50℃低温,旱生,不苛求土壤水分。我区自60年代初,开始在沙地实验造林获得成功。历年沙地4、5、6月都出现程度不同的大气干旱
Foreword Pinus sylvestris L.var.mongolica Litvin. Evergreen trees, mainly distributed in the northern part of the Greater Hinggan Mountains, Hulunbeier grassland dune. Tree often up to 15 ~ 20m, up to 30m, the maximum diameter of about 1.0m, life expectancy of up to 200 years. Trunk straight, good material. Cold-resistant, can withstand -40 ~ -50 ℃ low temperature, drought, not demanding soil moisture. My district since the early 60s, started in the experimental success of afforestation in Saudi Arabia. In the past four years, there were different degrees of atmospheric drought in the sandy land in April, May and June