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青川县地处四川盆地北部边缘,地貌类型以低山和中山为主,丘陵和平坝较少.全县林业用地309万亩,无林地面积约47万亩,其中坡度在25—35°占73%,低山丘陵地带属亚热带湿润季风气候,年平均气温13.7—15.7℃,年降水量866—1471mm,年平均相对湿度75—83%,全年日照时数1100—1500小时,无霜期215—270天.土壤以山地黄壤为主,pH5.0—6.0,土层厚70cm以上者占80%以上.该县定为省营造速生丰产林基地.现将几个树种的野外标准地生长调查资料,经内部计算和综合整理于后.
Qingchuan County is located in the northern margin of the Sichuan Basin, the main types of landscape to low mountain and Zhongshan, the hills and dam less .309 acres of the county forestry land, non-forest land area of about 47 acres, of which slope in the 25-35 ° accounted for 73 The hilly region belongs to the subtropical humid monsoon climate with annual average temperature of 13.7-15.7 ℃, annual rainfall of 866-1471mm and annual average relative humidity of 75-83%. The annual sunshine duration is 1100-1500 hours and the frost-free period is 215-270 days The soil is mainly composed of mountainous yellow soil, with the pH value of 5.0-6.0 and the soil layer thickness over 70cm, accounting for over 80% of the total area. Internal calculation and consolidation after.