不同修枝强度对红锥马尾松混交林幼林生长及光环境的影响  

Effects of Different Pruning Intensities on Growth and Light Environment of Castanopsis hystrix and Pinus massoniana Mixed Plantation

作　　者：罗创福 李万年 邓冬莲 杜旭 杨梅[2] 梁燕芳 LUO Chuangfu;LI Wannian;DENG Donglian;DU Xu;YANG Mei;LIANG Yanfang(Guangxi Zhuang Autonomous Region Qipo State-owned Forest Farm,Nanning 530031,China;College of Forestry,Guangxi University,Nanning 530004,China)

机构地区：[1]广西壮族自治区国有七坡林场,广西南宁530031 [2]广西大学林学院,广西南宁530004

出　　处：《北华大学学报（自然科学版）》2021年第5期665-671,共7页Journal of Beihua University（Natural Science）

基　　金：广西林业科技推广示范项目(gl2020kt01,gl2018kt04);广西创新驱动发展专项(桂科AA17204087-6).

摘　　要：以修枝2 a后的8 a生混交林为研究对象,设置不修枝和修掉树高1/3、1/2、2/3以下枝条4种修枝处理(分别记为T_(0)、T_(1)、T_(2)、T_(3)),采用单因素随机区组设计,研究修枝对红锥-马尾松混交林生长及光环境的影响,以针对不同树种筛选适宜的修枝强度.结果表明:1)修枝显著促进了两树种的平均树高、胸径和单株材积增长,红锥和马尾松分别在T_(3)和T_(2)处理下达到最高值;两树种的冠幅变化表现为红锥T_(0)>T_(1)>T_(2)>T_(3),马尾松T_(3)>T_(2)>T_(1)>T_(0).2)适度修枝提高了红锥和马尾松树干的干物质积累量和地上总生物量,两树种分别在T_(3)和T_(2)处理下达到最大值;树枝、树叶生物量均表现为T_(0)>T_(1)>T_(2)>T_(3).3)随着修枝强度的增大,两树种的叶面积指数显著减小,但平均叶倾角、透光率显著增大,增加了冠层有效光合面积,改善了林内光环境.相关性分析表明,修枝对红锥生长发育的影响比马尾松更大,促生效果更佳.综合来看,红锥和马尾松分别修枝至树高的2/3和1/2处是最适修枝高度,有利于培育红锥-马尾松复层混交林.In order to investigate the effects of pruning on the growth and light environment of Castanopsis Hystrix and Pinus Massoniana mixed plantation,and to select suitable pruning intensity for different tree species,the 8-year-old mixed plantation was studied after 2 years of pruning.A single factor random block design was adopted to set up four pruning treatments as follows:no pruning,pruning branches under the 1/3,1/2 and 2/3 of the tree height,marked as T_(0),T_(1),T_(2) and T_(3) respectively.The results showed that:1)Pruning significantly promoted the growth of average height,DBH and individual volume of the two species and the above indicators reached the highest value under T_(3) and T_(2) treatments,respectively in C.hystrix and P.massoniana;The crown width of the two tree species showed as follows:T_(0)>T_(1)>T_(2)>T_(3) for C.hystrix,T_(3)>T_(2)>T_(1)>T_(0) for P.massoniana.2)Moderate pruning increased the dry matter accumulation and aboveground biomass of C.hystrix and P.massoniana,which reached the maximum under T_(3) and T_(2) treatments,respectively,while the biomass of branches and leaves showed the following order:T_(0)>T_(1)>T_(2)>T_(3).3)With the increase of pruning intensity,the leaf area index of two species decreased significantly,but the average leaf angle and light transmittance increased significantly,which increased the canopy effective photosynthetic area and improved the light environment in the plantation.In conclusion,the optimal pruning height was 2/3 and 1/2 of tree height for C.hystrix and P.massoniana,respectively,which was beneficial to stratify the mixed plantation.

关 键 词：红锥 马尾松 修枝强度 生长 光环境 

分 类 号：S750[农业科学—森林经理学]