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以东北林业大学帽儿山实验林场老爷岭生态站11林班次生林区撂荒地上人工栽植的落叶松与天然侵入的水曲柳混交林为研究对象,在所设置的固定标准地内,分别以落叶松、水曲柳和其它阔叶树为目的树,调查半径1～6m内树木的株数和胸径;并以每株树为圆心测定最近8株树之间的距离、胸径和冠幅,获得基本数据。应用Alemdag模型计算竞争指数,并用方差分析和数量化模型方法进行了分析。结果表明,落叶松的种内竞争大于种间竞争,且落叶松与水曲柳之间的竞争相对最小。就试验地的条件而言,在20～30年生时每公顷保留2800株左右,落叶松与水曲柳混交比以2∶1为宜,这样不仅可以改善林地条件,而且可以提高林分生产力。
Taking Artemisia lanceolata mixed with larch artificial mixed forest in fallow land of secondary forest in No.11 forest of Laoyeling Ecological Station of Maoershan Experimental Forest Farm in Mao’er Mountain, Northeast Forestry University as the research object, in the set standard fixed place, , Fraxinus mandshurica and other broad-leaved trees were selected as the objective tree to investigate the number of trees and the diameter of the trees within the radius of 1 ~ 6m. The distance, diameter at breast height and crown width of the nearest eight trees were measured with each tree as the center to obtain the basic data. The Alemdag model was used to calculate the competition index and analyzed by ANOVA and quantitative models. The results showed that the interspecific competition of larch was greater than interspecific competition, and the competition between larch and ash was the least. In terms of experimental conditions, about 2 800 plants per hectare are preserved at 20 to 30 years of age, and the ratio of larch to ash is 2: 1, which can not only improve the woodland conditions but also improve the stand productivity.