生态营林桉树人工林林木生长动态分析

Dynamic Analysis of Tree Growth in Ecological Management in Eucalyptus Plantation

关键词:  桉树  珍贵树种  混交类型  林分生长  动态变化

Key words:  Eucalyptus spp.  precious tree species  mixed type  stand growth  dynamic change

摘要:

为阐明轮伐期内不同类型桉树(Eucalyptus spp.)人工混交林的生长动态特征及变化规律，选择于2012年在中国林业科学研究院热带林业实验中心青山实验场采用生态营林制度营造的桉树×降香黄檀混交林(Eucalyptus×Dalbergia odorifera，MED)、桉树×望天树混交林(Eucalyptus×Parashorea chinensis，MEP)、桉树×红锥混交林(Eucalyptus×Castanopsis hystrix，MEC)和桉树纯林(PEU)为研究对象，设置固定监测样地，基于桉树第一轮伐期内的3次林分调查(2014、2016、2018年)，分析不同混交林桉树和珍贵树种的胸径、树高、单株材积和林分蓄积量动态变化特征。结果表明，监测期内，4种林分类型林木胸径、树高、单株材积和林分蓄积量均随林龄显著增加；混交林中降香黄檀、红锥及望天树均可显著促进桉树胸径、树高、单株材积及林分蓄积量的生长，促进作用大小表现为MED＞MEC＞MEP；不同混交类型中珍贵树种的胸径、树高、单株材积及林分蓄积量均表现为MEC＞MEP＞MED，林分总蓄积量表现为MED (212.0 m³/hm²)＞MEC (203.7 m³/hm²)＞MEP (184.9 m³/hm²)＞PEU (141.1 m³/hm²)；4种类型林分中桉树的胸径、树高、单株材积和林分蓄积量年平均生长量总体表现为MED＞MEC＞MEP＞PEU,珍贵树种则表现为MEC＞MEP＞MED。研究表明，混交可以明显促进桉树的生长，3种混交林分中桉树的胸径、树高、单株材积及林分蓄积量生长均显著高于桉树纯林，其中MED林分中桉树的生长更具优势，珍贵树种的生长则以红锥最优，望天树次之，降香黄檀最低。3种混交林均可作为今后桉树混交林经营的参考模式。

Abstract:

In order to clarify the growth dynamic characteristics and variation rules of different types of Eucalyptus spp.artificial mixed forests during the rotation period,the Eucalyptus×Dalbergia odorifera mixed forest (MED),Eucalyptus×Parashorea chinensis mixed forest (MEP),Eucalyptus×Castanopsis hystrix mixed forest (MEC) and Eucalyptus pure forest (PEU) were selected as the research objects,which were constructed by using the ecological forest management system in Qingshan Experimental Farm of Experimental Center of Tropical Forestry of Chinese Academy of Forestry in 2012.The fixed monitoring plots were set up based on three stand surveys during the first rotation period of Eucalyptus (2014,2016 and 2018).The dynamic change characteristics of DBH,tree height,individual volume and stand volume of Eucalyptus and precious tree species in different mixed forests were analyzed.The results showed that during the monitoring period,the DBH,height,individual volume and stand volume of the four stand types increased significantly with the age.In mixed forest,D.odorifera,C.hystrix and P.chinensis all significantly promoted the growth of DBH,tree height,individual tree volume and stand volume of Eucalyptus,and the promoting effect was shown as MED>MEC>MEP.The DBH,tree height,individual tree volume and stand volume of precious tree species in different mixed types were shown as MEC>MEP>MED.The whole stand volume was MED (212.0 m³/hm²)>MEC (203.7 m³/hm²)>MEP (184.9 m³/hm²)>PEU (141.1 m³/hm²).The annual average growth of DBH,tree height,individual volume and stand volume of Eucalyptus in the four types of stands was MED>MEC>MEP>PEU,while that of precious tree species was MEC>MEP>MED.The results showed that mixing could significantly promote the growth of Eucalyptus. The growth of DBH,tree height,individual volume and stand volume of Eucalyptus in the three mixed forests were significantly higher than those of Eucalyptus pure forest.Among them,the growth of Eucalyptus in MED forest was more advantageous.The growth of precious tree species was the best,followed by P.chinensis,and the lowest was D.odorifera. The three mixed forests can be used as a reference model for the management of Eucalyptus mixed forests in the future.