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山杨是我省次生林区的主要树种之一,具有生长快、分布广、面积大的特点。研究山杨的生长过程,与合理经营山杨林,特别是抚育间伐,提供科学依据。本文根据山杨的年令与树高、年令与树径是二次抛物线相关,年令与材积呈三次抛物线相关、与生长率呈幂函数相关;阳坡与阴坡有显著差异的特性,分别提出了相应的生长模型。
Aspen is the secondary tree forest in our province one of the main species, with fast growth, wide distribution, large area characteristics. To study the growth process of Populus euphratica and to provide a scientific basis for the rational management of Populus euphratica, especially for tending thinning. In this paper, according to the annual and tree height of aspen, the year and year are related to the quadratic parabola, and the annual parabola is related to the volume by cubic parabola and the growth rate is a power function. There are significant differences between sunny slope and shady slope, Respectively, the corresponding growth model.