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1987年以来,我们作了云杉改造型母树林经营技术试验,现将试验初报如下.一、自然概况:云杉母树林位于丹巴林业局——四林场大坝口,海拔3200m,地形开阔,属沟谷口冲积扇,面积210亩.林地较平坦,坡度4度,土壤为沙质壤土,pH值5.5,气候具高山峡谷区气候特点,光照充足,年降雨量750mm,年平均气温8℃左右.云杉母树林属于天然散生纯林,树种为鳞皮和紫果云杉,伴有少量冷杉和桦木,林龄20—4O年,林分密度1300株/ha,平均胸径12.5cm,平均树高7m,平均树冠8.5m~2,郁闭度0.4—0.8,林木生长良好,10年平均年径生长0.7cm,树高年生长50—80cm,下木为沙棘、枸子、忍冬等.
Since 1987, we have made a trial operation of spruce reformed mother tree experiment, the first report is as follows: First, the natural profile: The spruce tree forest is located in Danba Forestry Bureau - four forest field dam mouth, elevation 3200m, topography Open, is a alluvial fan at the mouth of the valley, an area of 210 mu. Woodland is relatively flat, the slope of 4 degrees, the soil is sandy loam, pH 5.5, climate with mountain gorge climate characteristics, adequate sunshine, annual rainfall 750mm, annual average temperature 8 ℃ spruce forests belong to the natural pure natural forest, the species of scales and purple spruce, with a small amount of fir and birch, age 20-4O years, stand density 1300 / ha, the average diameter of 12.5cm , The average height of tree 7m, the average tree crown 8.5m ~ 2, canopy density 0.4-0.8, trees grow well, the average annual growth of 10 years 0.7cm, tree growing 50-80cm, underglasova, cotoneaster, honeysuckle Wait.