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世界上很多地区基于桉树的商业价值开展了桉树人工林的经营。密度管理在桉树人工林经营管理中往往成为很重要的手段。该研究以不同林龄的桉树人工林为研究对象,在森林郁闭和树木生长竞争期,量化其森林郁闭度和冠层结构。通过对桉树人工林的调查,研究了其林地指数对其林冠郁闭度的影响。结果表明:立地指数对郁闭度影响不大,在好的立地条件下森林郁闭度有轻微的影响。基于树冠投影面积比和树冠直径和胸径的比值研究表明:桉树林在4年生时开始郁闭。对不同林龄的相对间距RS值的研究表明:相对间距值在第4年时表现出快速降低,到21年的时候逐渐变得相对平缓。桉树林在前3年表现出快速的高生长,由于速生,其在密度上没有多大变化。4年生桉树林由于死亡率导致树木个体数量的减少,影响了RS值,导致其逐渐下降。
Eucalypt plantations are operated in many parts of the world based on the commercial value of eucalyptus. Density management often becomes a very important tool in the management of eucalypt plantations. In this study, Eucalyptus plantations of different ages were taken as research objects to quantify the forest canopy and canopy structure in the period of forest canopy and tree growth competition. Through the investigation of Eucalyptus plantation, the influence of forest index on its canopy density was studied. The results showed that the site index had little effect on the canopy density, and had a slight influence on the forest canopy density under the good site conditions. Based on the crown area ratio and crown diameter and DBH ratio studies show that: eucalyptus forest 4 years old began to close. Studies on the RS value of relative distance between different stand ages showed that the relative spacing value showed a rapid decrease at the 4th year and gradually became relatively flat by 21 years. Eucalyptus forests showed rapid high growth in the first three years and did not change much in density due to their fast growing. 4-year-old eucalyptus forest as a result of mortality led to a reduction in the number of trees individuals, affecting the RS value, resulting in its gradual decline.