柳杉苗木生物量初步研究

Approaching to Stock Biomass of Cryptomeria

以生物量为指标,把柳杉苗圃生产力划分成高、中、低三等,生物量大于300kg/亩的属高生产力苗圃,200～300kg/亩的属中等生产力苗圃,小于200kg/亩属低生产力苗圃。以苗高、地径与苗木根、茎、枝、叶各器官干重的相关性来确定适宜的育苗密度和苗木分级标准,即采用经验公式W=a(D^2H)~b来确定苗木生物量和茎、根、枝、叶各器官产量与苗高、地径间的回归关系。适宜的育苗密度为6～7万株/亩,苗木分级以茎根比2.5～3.0为标准。

Taking biomass as index, the productivity of cryptomeria Nurseries was divided into three grades: (1) biomass more than 300kg permu belonging to high-productivity nurseries; (2) biomass range from 200 to 300 kg permu belong to mid-productivity nurseries(3) biomass less than 200 kg permu belong to low-productivity nurseries. The correlation between the biomass propation among plants for root, sterm, branch and foliage dry weight and height of plants and groudline basal area was described in this study. The mathematical models (based on W = a(D2H)b were deveioped for determining appropriate density of breeding and ratio between sterms and roots.