目标树经营对火炬松人工林天然更新的初期影响  

Early Effect of Crop Tree Management on Natural Regeneration of Pinus taeda Plantation

作　　者：高涛 陈兴国 陈明泉 吴金虎 周瑜 史帅 汪洋[2] Gao Tao;Chen Xingguo;Chen Mingquan;Wu Jinhu;Zhou Yu;Shi Shuai;WangYang(Panshiling Forest Farm of Zhongxiang City,Zhongxiang,Hubei 431900,China;Hubei Ecology Polytechnic College,Wuhan,Hubei 430200,China)

机构地区：[1]湖北省钟祥市盘石岭林场,湖北钟祥431900 [2]湖北生态工程职业技术学院,湖北武汉430200

出　　处：《绿色科技》2022年第23期173-177,共5页Journal of Green Science and Technology

基　　金：中德财政合作林业重大研究项目(编号:zdczhz2021ky08,zdczhz2021ky09)。

摘　　要：火炬松人工林是钟祥市盘石岭林场造林面积最大的人工林,火炬松种植15 a后生长缓慢。为探究林下天然更新能力以实现火炬松人工林近自然化改造,以盘石岭林场1 hm^(2)固定样地内62个25 m^(2)样方(5 m×5 m)天然更新数据为基础,对比目标树经营1 a后不同间伐强度即:轻度间伐LT(14.4%)、中度间伐MT(25.3%)、强度间伐HT(36.0%)和对照CK(0%)对林下天然更新的影响。结果表明:不同间伐强度天然更新物种种数均高于CK,乔木更新种的植物种数的增幅大于灌木层物种;增大间伐强度促进了天然更新的乔木物种优势,落叶更新物种在数量和优势度上均远高于常绿物种,且平均苗高逐渐增大。物种丰富度随间伐强度增大而增大;随间伐强度增大,物种多样性指数均呈减小—升高—减小趋势;不同间伐强度天然更新株树密度均高于CK。据此可见,间伐促进了物种天然更新,目标树经营适合火炬松人工林的近自然化改造目标。Pinus taeda plantation is the largest plantation in size in the Panshiling forest farm of Zhongxiang City, and the growth potential of Pinus taeda declines after 15 a planting. In order to investigate the natural regeneration capacity of the understory to realize the near-naturalization transformation of Pinus taedast, the natural regeneration data from 62 sample squares(each 25 m^(2) with 5 m×5 m in size) in 1 hm^(2) fixed sample plots of Panshiling forest were used as the basis for comparison of the effects of different thinning intensities, namely, light thinning LT(14.4%), moderate thinning MT(25.3%), heavy thinning HT(36.0%) and control CK(0%), on natural regeneration in the understory after 1 a period of operation of crop tree management. The number of naturally regenerated species was higher than that of CK at different thinning intensities, and the number of tree regeneration species increased more than that of shrub layer species;increasing thinning intensity promoted the dominance of naturally regenerated tree species, and deciduous regeneration species were much higher in number and in dominance than evergreen species, and the average seedling height gradually increased. The species richness increased with increasing thinning intensity;the species diversity index showed a decreasing-increasing-decreasing trend with increasing thinning intensity;the density of naturally regenerated trees with different thinning intensities was higher than that of CK. Therefore, it is believed that thinning promotes the natural regeneration of species;the target tree management is suitable for the close-to-nature transformation target of Pinus taeda stands.

关 键 词：目标树经营 天然更新 间伐强度 多样性 火炬松 

分 类 号：S791.255[农业科学—林木遗传育种]