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抚育间伐是从幼林郁闭到林木成熟之前一个龄级的时期内,在林内多次适时地伐除部分林木,给目的树种创造良好的生长环境,藉以调整林分的组成、密度,改善林分的卫生状况,缩短林分的工艺成熟期,提高林木生长量和木材质量,增强森林的多种效益,并通过间伐获得一部分木材,以满足当地生产生活对木材的需求,还从中获得一些经济收入,扩大林业再生产。我区人工林的树种组成,主要有杨、柳、榆等阔叶树种,还有落叶松、油松、樟子松等针叶树种。现就杨柳类和落叶松的幼中龄人工林抚育间伐标准的典型调查,介绍如下。一、杨柳类: 乌兰察布盟商都县西井子公社,在干旱草原非灌区营造杨树农田防护林,初植密度为每亩333株,第
Tending thinning is the period from the standstill of young forests to the stage of one age before maturity of trees, and the timely removal of some forest trees in the forest to create a good growth environment for the purpose of tree species, in order to adjust the composition, density and forest stand improvement Of the state of health, shorten the maturity of the forest stand, improve forest growth and timber quality and enhance the forest’s multiple benefits, and get some wood through thinning to meet the local production and demand of timber, but also get some economic income , Expand forestry reproduction. Tree species composition of the plantation in our district mainly includes broadleaf species such as poplar, willow and elm, as well as coniferous species such as larch, Chinese pine and Pinus sylvestris var. Mongolica. Now on the willow classes and larch juvenile plantation tending thinning standard survey, described below. First, the willow categories: Ulan Qab League Shangxi Xijingzi commune, in the arid steppes non-irrigated area to create poplar farmland shelterbelt planting density of 333 plants per acre, the first