基于结构优化的择伐对锐齿槲栎天然林结构与生长的影响

以甘肃小陇山林区锐齿槲栎天然林为对象，分析基于结构优化的择伐方式林分和未择伐林分的树种组成、生物多样性、径级结构、空间结构及生长之间的差异。结果表明：1)2008-2018年，择伐后的林分密度、平均胸径、平均树高、胸高断面积和树种数均呈现出先下降后增加的趋势，而Shannon-Wiener指数值和Pielou均匀度指数呈现增加的趋势；未择伐样地林分的密度、树种数、Shannon-Wiener指数值和Pielou均匀度指数呈现下降的趋势，而平均胸径、平均树高和断面积呈现增加的趋势；2)择伐样地和未择伐样地10 a间林木径级分布结构和林木的分布格局没有改变；而择伐样地的林木混交程度不断提高，未择伐样地的林木混交程度下降；3)2次调查间隔期内，择伐样地的胸径平均相对生长率分别较未择伐高18.4%和55.2%,胸高断面积相对生长率分别较未择伐高18.2%和54.4%;4)2008-2013年，择伐样地的进阶率和死亡率均高于未择伐样地，而在2013-2018年，择伐样地死亡率大幅下降。5)择伐样地和未择伐样地内各径级间的胸径平均生长率呈现随径级的增加而下降的趋势，且各径级间差异显著。择伐样地和未...

Effects of Structural Optimization Based Thinning on the Structure and Growth of Quercus aliena var.acuteserrata Natural Forest

This study explored the influences of selective thinning on the structure and growth dynamics of Quercus aliena var.acuteserrata natural forest which was managed based on structural optimization to provide a basis for the management of Q.aliena var.acuteserrata natural forest.We analyzed and compared the basic forest stand factors,composition and diversity,diameter structure,spatial structure and growth in both the managed and control plots by using the K-S significant difference test method and the non-repetitive two-way ANOVA method.The results present that:1)After selective thinning,stand density,average DBH,average tree height,average basal area and the number of tree species in the treatment plot showed the trend of decreasing at the beginning and then increasing,and the Shannon-Wiener index and Pielou evenness indices showed an increasing trend.However,the density,tree species,Shannon-Wiener index and Pielou evenness index in the control plots showed a decreased trend,while the average DBH,average tree height and basal area showed an increasing trend.2)There were no fundamental changes in the patterns of diameter distribution and the spatial distribution of forest trees in the treatment and the control plots during the 10-year period.The mingling index in the management plot increased continuously,while the control plot decreased.3)During the two survey intervals,the relative growth rates of DBH in the managed plot were 18.4% and 55.2 % higher than the control plot,and the relative growth rates of basal area in the managed plot were 18.2% and 54.4% higher than control plot.4)The tree ingrowth rate and mortality rate of the managed plot were higher than the control plots from 2008 to 2013 and the mortality rate of the managed plot decreased significantly between 2013 to 2018,while the change in the ingrowth rate and mortality of the control plot were less variable from 2008 to 2018.5)Both the relative average growth rate of DBH of the management plot and control plot decreased with the increase of the diameter classes,and the difference between the internal diameter classes was significant,but the difference was not significant during the two survey intervals.There was no significant difference in the relative average growth rate of DBH between the management plot and the control plot from 2008 to 2013,and the difference was significant from 2013 to 2018.The selective thinning method based on structural optimization can maintain the stability of the continuity stand structure,promote the growth and renewal of forest trees,and improve the diversity and the degree of mixture of forest stands.Future research are needed to systematically evaluate and monitor the long-term change in the dynamics of the population,the competitive situation,and the growth of subject trees.