不同经营模式对油松人工林林分生长短期影响

Initial Effect of Different Managements on the Growth Dynamics of Pinus tabuliformis Plantations

为了探究不同森林经营方式林分生长动态变化情况,于内蒙古赤峰市旺业甸林场油松人工林中选取油松中龄林和近熟林设置近自然经营、常规经营和未经营样地,根据2013、2016年和2019年3次调查,分析对比不同经营模式下林分蓄积生长量、胸径、胸高断面面积和单木材积量单木生长量,林分胸径分布和林分垂直分层生长量的动态变化。结果表明,中龄林近自然经营和常规经营方式下的PAI(年蓄积生长量)均大于未经营,近熟林6 a间近自然经营方式下PAI为12.31 m^(3)·hm^(-2)·a^(-1),大于常规经营和未经营;中龄林平均胸径单木生长量6 a间表现为近自然经营(0.58 cm·a^(-1))>常规经营(0.48 cm·a^(-1))>未经营(0.31 cm·a^(-1)),近熟林表现为近自然经营(0.69 cm·a^(-1))>未经营(0.49 cm·a^(-1))>常规经营(0.46 cm·a^(-1));近自然经营方式下油松人工林6 a间单株胸高断面面积生长量、单株立木材积生长量均显著大于常规经营和未经营;近自然经营方式下的油松人工林上层胸径、胸高断面、蓄积年生长量都大于其他经营方式,近自然经营大径阶树木比例增长幅度最大。由此得出结论,近自然经营有利于林木胸径、林木单株胸高断面面积和单株立木材积量的生长,同时还会提高林分大径级林木株数比例,更有助于提高人工林木质量。

In order to explore the growth dynamic changes of stand growth under different forest management modes,in this study,middle-aged and near mature Pinus tabuliformis plantations in Wangyedian Forest farm of Chifeng,Inner Mongolia were selected as research objects to conduct 3 types of forest management:close-to-natural management(CNM),conventional management(CM),and non-management(control).According to the data of three surveys in 2013,2016 and 2019,the dynamic changes of diameter at breast height(DBH),basal area at breast height(BABH),volume,single tree growth,stand horizontal structure growth and stand vertical structure growth were analyzed and compared among different management types.The results showed that the periodic annual increment(PAI)of middle-aged forest under CNM and CM was higher than that of the control,and PAI of nearly mature forest under CNM was 12.31 m^(3)·hm^(-2)·a^(-1),which was higher than that of CM and the control.The average DBH growth of the single tree of middle-aged forest was in the order of CNM(0.58 cm·a^(-1))>CM(0.48 cm·a^(-1))>control(0.31 cm·a^(-1))in 6 years;for the near mature forest,the order was CNM(0.69 cm·a^(-1))>control(0.49 cm·a^(-1))>CM(0.46 cm·a^(-1));under CNM,the growth of breast height section area of individual tree in 6 years was significantly larger than that of CM and control.The upper DBH,BABH and volume annual growth under CNM were higher than CM and the control.It was concluded that compared with other management methods,the CNM mode was conducive to the growth of DBH,BABH of single tree and volume of single tree,CNM was beneficial to the increase of the proportion of large diameter trees,and was more helpful to improve the quality of artificial trees.