立地指数及密度对杉木幼龄林凋落物分解特征和热值的影响  

Site indices and densities on growth of young Cunninghamia lanceolata plantation influence of litter decomposition characteristics and calorific value

作　　者：朱琴 关恒锋 杨浩 许祖元 曹光球[1,2] 曹世江 ZHU Qin;GUAN Hengfeng;YANG Hao;XU Zuyuan;CAO Guangqiu;CAO Shijiang(College of Forestry,Fujian A&F University,Fuzhou 350002,Fujian,China;Chinese Fir Engineering Research Center of National Forestry and Grassland Administration,Fujian A&F University,Fuzhou 350002,Fujian,China)

机构地区：[1]福建农林大学林学院,福建福州350002 [2]福建农林大学国家林业和草原局杉木工程技术研究中心,福建福州350002

出　　处：《中南林业科技大学学报》2025年第4期87-97,共11页Journal of Central South University of Forestry & Technology

基　　金：国家重点研发计划项目(2021YFD2201302)。

摘　　要：【目的】探讨不同立地指数及密度下杉木幼龄林的养分流动和能量循环,筛选出养分与能量流动最快的立地指数和林分密度,为杉木幼龄林可持续经营提供重要理论基础。【方法】选取永安国有林场永浆工区7年生杉木人工林为试验林,采用双因素完全随机区组法设计,设置3种立地指数:16立地指数(S)、18立地指数(E)、20立地指数(T);同时设置3种林分密度:1200株·hm^(-2)(12)、1500株·hm^(-2)(15)、1800株·hm^(-2)(18);共9种处理:S12、S15、S18、E12、E15、E18、T12、T15、T18。【结果】9种处理凋落物残留率随分解时间不断下降,其中E15的凋落物分解最快,凋落物分解50%、95%所需时间最短,分别为1.22、5.26 a。凋落物养分含量的变化规律各不相同,随着分解时间的推移,凋落物碳含量呈现下降—上升—下降的趋势,氮含量总体呈减少趋势,磷含量呈波动中有所增加的状态。各处理随着凋落物的分解,凋落物热值总体上呈现出波动下降的趋势,S18、E15、T12处理凋落物热值分解速度快。可见,凋落物热值下降能促进能量归还与循环。【结论】T12、E15、T18处理凋落物养分释放与能量流动速度更快。【Objective】In order to explore the nutrient flow and energy cycling of young Cunninghamia lanceolata under site index and density,and to screen out the site index and stand density with the fastest nutrient and energy flow,which is of great significance for the sustainable management of young Cunninghamia lanceolata forest.【Method】The 7-year-old Cunninghamia lanceolata plantation in the Yongjiang area of Yong’an state-owned forest farm was selected as the experimental forest,and three site indices were set by twofactor complete random block design:16 site index(S),18 site index(E)and 20 site index(T).At the same time,three stand densities were set:1200 plants·hm^(-2)(12),1500 plants·hm^(-2)(15),1800 plants·hm^(-2)(18),and a total of 9 treatments(S12,S15,S18,E12,E15,E18,T12,T15,T18).【Result】The residue rate of litter in the nine treatments decreased with the decomposition time,among which E15 had the fastest litter decomposition,and the time required for 50%and 95%litter decomposition was the shortest,which were 1.22 and 5.26 years,respectively.With the passage of decomposition time,the litter C content showed a decreasing-rising-decreasing trend,the N content showed a decreasing trend,and the P content showed a fluctuating state.With the decomposition of litter,the calorific value of litter showed a fluctuating and decreasing trend in general.S18,E15 and T12 treated litter calorific value decomposition rate quickly,which can be seen that the calorific value of litter decreases quickly,which can promote energy return and circulation.【Conclusion】T12,E15 and T18 treatments resulted in faster nutrient release and energy flow in litter.

关 键 词：杉木 凋落物 养分 热值 

分 类 号：S723.1[农业科学—林木遗传育种]