论文部分内容阅读
黑茶山林局位于吕梁山脉的西侧中段,海拔1200～2260米,年降水量500毫米左右,冬、春季干旱多风,水土流失严重,给造林工作带来了较大困难。近年来华北落叶松造林成活率不高,经济效益低下。我们针对这个问题在1983、1984两年的造林实践中,首先对华北落叶松苗木高度与造林成活率的关系进行了初步调查研究,其结果表明:来源于同一地理种源的种子育苗后,苗木高度不同,对造林成活率、保存率有着明显的影响。在我局的具体条件下,造林苗木以选用苗高20～50厘米,地径在0.3厘米以上,根系较完整的二年生苗为好。一、造林苗木状况本区上山造林苗木全部采用同一种源的落叶松二年生留床苗,就地育苗,就近造林。造林苗木规格一般高15厘米以上,地径
The Black Tea Forest Bureau is located in the middle of the western Lvliang Mountains with an elevation of 1,200 to 2,260 meters and an annual rainfall of about 500 millimeters. It is arid and windy in winter and spring with serious soil erosion, which brings great difficulties to the afforestation. In recent years, Larix principis-rupprechtii afforestation survival rate is not high, low economic efficiency. In response to this problem in 1983 and 1984, two years of afforestation practice, first of all, Larix principis-rupprechtii seedling height and survival rate of the relationship between the initial investigation, the results showed that: seed germination from the same geographical provenance seedlings Different height, the survival rate of afforestation, preservation rate has a significant impact. Under the specific conditions of our bureau, afforestation seedlings should use the height of 20-50 cm, the diameter of 0.3 cm or more, and the more complete two-year-old seedlings. First, the situation of afforestation seedlings All the afforestation seedlings in this area use the same source of larch two years stay bed seedlings, local nursery, the nearest afforestation. Afforestation seedling specifications generally higher than 15 cm, diameter