南京林业大学学报（自然科学版）2017，Vol.41Issue(4)：101-107,7.DOI:10.3969/j.issn.1000-2006.201606040
近自然化改造对桂南马尾松和杉木人工林结构特征的影响
Effects of close-to-nature transformation on structure characteristics of Pinus massoniana and Cunninghamia lanceolata plantations
摘要
Abstract
[Objective] The close-to-nature transformation changes the forest composition and stand structure and thus,affects the tree growth and stand stability.Therefore,a study on the effects of close-to-nature transformation on stand structure has important significance in improving the quality of degrading plantations and producing large-diameter timber.[Method]This study focused on Pinus massoniana and Cunninghamia lanceolata plantations,afforested in 1993 and close-to-nature transformated in 2008.Three parameters (mingling,uniform angle index,and neighborhood comparison) were considered to compare the changes in stand spatial structure before and after close-to-nature transformation.[Results] ① The diameter of control stands followed normal distribution,while the close-to-nature transformation stands showed the reversal “J” type.The tree height of control stands was a single peak type,whereas that of close-to-nature transformation plantations showed a double peak.② The close-to-nature transformation improved stand mingling significantly,the average mingling increased from 0.00 and 0.16 to 0.82 and 0.89 in the P.massoniana and C.lanceolata control stands and their close-to-nature stands respectively.③ Close-to-nature transformation has little effect on the uniform angle index,it changed from uniform distribution to reunion distribution in C.lanceolata stands;however,it has been in a random distribution state in P.massoniana stands.④ The number of dominant and sub-dominant individuals were increased after close-to-nature transformation.The average neighborhood comparison of P.massoniana and C.lanceolata close-to-nature stands was 0.40 and 0.46 respectively,whereas there were generally medium individuals in the control stands.[Conclusion] In the perspective of non-spatial structure,close-to-nature transformation improves the composition of forest species,and the diameter of trees is transferred to an inverted “J” type as uneven aged forest.In terms of the stand spatial structure,the characteristic of artificial pure forests which were zero or less mixed with uniformly and evenly distributed tree species has been weakened by the transformation.In the close-to-nature forests,interplanted and natural regenerated species are growing well to increase the stand mingling,biodiversity,and optimize the forest spatial structure,where could become different-aged multilayer compound forests.关键词
人工林/近自然化改造/林分结构/角尺度/混交度/大小比数Key words
plantation/close-to-nature transformation/stand structure/uniform angel index/mingling/neighborhood comparison分类
农业科技引用本文复制引用
刘志龙,明安刚,贾宏炎,蔡道雄,马跃,王亚南,孙冬婧..近自然化改造对桂南马尾松和杉木人工林结构特征的影响[J].南京林业大学学报（自然科学版）,2017,41(4):101-107,7.基金项目
中国林科院基本科研业务费专项资金项目(CAFYBB2014QA033) （CAFYBB2014QA033）
广西林业科技项目(桂林科字[2014]第41号) （桂林科字[2014]第41号）
广西自然科学基金项目(2014GXNSFBA118084) （2014GXNSFBA118084）
