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白龙江属亚高山针叶林区,森林的自然分布具明显垂直带谱,从下到上依次为针阔混交林藓类箭竹针叶林,杜鹃冷杉林,高山灌丛及高山草甸。树种以冷杉、云杉为主,冷杉占总蓄积量的54.7%,云杉占20.7%,随着森林的开发利用,大面积的云杉(以 Picea asperata 为主)人工更新始于1961年。近两年,对云杉人工林进行了一次调查,本文根据部分调查资料整理并进行粗浅分析,以供商榷。一、人工林生育情况林区云杉更新的主要范围是海拔2000～3300米,现有成效面积四十余万亩,有的已郁闭形成稳定群落。由于立地条件和经营措施的差别,群落形态结构相异,有的长势弱,林相参差不齐,有的展现速生趋势,为天然林所莫及。以沙滩林场20年生(包括苗令,下同)为例:海拔2800米以下,一般树高5米胸径6厘米左右,而集约经营的树高达7.57米,胸径10.5厘米,均提高约三分之一。
Bailongjiang sub-alpine coniferous forest area, the natural distribution of the forest with a significant vertical band spectrum, from condolence coniferous and broad-leaved mixed forest moss arrow coniferous forest, azalea fir forest, alpine scrub and alpine meadow. The main species is fir and spruce. Fir trees account for 54.7% of the total stock and spruces account for 20.7% of the total stock. With the development and utilization of the forest, large-area spruce (mainly Picea asperata) artificial regeneration began in 1961. In the past two years, a survey of spruce plantations has been carried out. This article is based on some survey data and is superficially analyzed for discussion. First, the plantation of plantation forest spruce regeneration of the main range is 2000 ~ 3300 meters above sea level, the existing effective area of more than 400000 acres, and some have closed form a stable community. Due to the difference of site conditions and management measures, the community structure is different, some are weak, the forest is uneven, and some show the fast-growing trend, which is beyond the scope of natural forest. Take the 20-year-old sandy beach farm (including Miao Ling, the same below) as an example: Below 2800 meters above sea level, the average tree height is 5 centimeters and the breast diameter is about 6 centimeters. However, the intensive management tree is 7.57 meters high and the diameter at breast height is 10.5 centimeters, one.