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油松是我国西北、华北和东北南部的黄土高原和沟壑区营造用材林、水土保持林和农田防护林的良好树种。当前,确定合理的造林密度是生产上急待解决的技术问题之一。为探求人工油松幼林间伐抚育的适宜密度,我们对桥山林区不同密度的人工油松幼林进行了调查。现将调查结果,简述如下。一、造林密度对林木生长的影响1.造林密度与幼林郁闭期的关系:幼林郁闭的迟早,与初植密度有关。一般是密者早,疏者迟。据调查,不同密度的人工幼林,达到郁闭状态所需要的年限不同(表1),
Pinus tabulaeformis is a good tree species for planting timber forest, soil and water conservation forest and farmland shelterbelt in the Loess Plateau and the gully region of Northwest, North China and South East of China. Currently, determining the reasonable planting density is one of the technical problems to be solved urgently in production. In order to explore the appropriate density of artificial sapling young thinning, we conducted a survey on different density artificial Pinus tabulaeformis young plantation in Qiaoshan. The survey results are summarized below. First, the impact of planting density on the growth of trees 1. Afforestation density and young canopy relationship: young plant canopy closed sooner or later, and the initial planting density. Generally close early, sparse late. According to the survey, different density of young plantations to reach the canopy state need different years (Table 1),