摘要
【目的】探究1973—2018年我国桉树人工林资源变化情况、生产力及碳汇能力,揭示桉树人工林连续种植下土壤肥力消耗问题和生产力变化规律,客观评价桉树人工林对保障我国木材供给、保护天然林资源、增强森林碳汇能力和缓解气候变化的贡献,并为制定桉树人工林可持续经营政策提供科学依据。【方法】基于1973—2018年9次全国森林资源清查3 564块桉树样地调查数据以及2003、2016年2期全国林地一张图数据和气象资料等,分析桉树人工林空间分布动态变化,并连续跟踪固定样地桉树变化,根据1994—2018年5期25年桉树人工林固定样地蓄积量数据,定量评价我国桉树人工林的生产力、碳积累能力、弃种率及其原因,构建桉树人工林弃种率模型和生产力模型。【结果】桉树在我国的适宜栽植范围为年均气温19^21℃、年降水量1 400^1 600 mm、海拔0^300 m的区域。全国桉树人工林年均生产力一般为4.14^8.57 m^3·hm^(-2)a^(-1),以海南、广东、广西和福建4省(区)较高,2^3年生桉树人工林接近40 m^3·hm^(-2)a^(-1);据第九次(2014—2018年)全国森林资源清查数据,桉树人工林每公顷年均固碳量为5.29 t·hm^(-2)a^(-1),比同地区速生树种马尾松和杉木人工林分别高2.95和2.18倍。尽管桉树人工林采伐年龄低,46%的采伐量用于造纸,但仍有54%的采伐量以板材形式长期固碳,碳汇功能仍很强。桉树是重要用材树种,虽然全国桉树人工林面积占人工林总面积的6.85%,但木材年采伐量占全国人工林采伐量的17.96%以上,其中广东和广西桉树人工林面积占其人工林总面积的30.32%和34.91%,采伐量分别占66.29%和49.97%。桉树生长旺盛,地力消耗较大,每隔5年原桉树种植面积弃种率25%以上,10和20年时的累计弃种率分别接近50%和75%,存在长期连续种植后地力严重衰退、难以再造林的风险。【结论】通过控制桉树人工林连载经营周�
【Objective】It is important to study the resource changes,productivity and carbon sink capacity of Eucalyptus plantation forests in China during 1973—2018,with a view to revealing the soil fertility depletion of Eucalyptus plantation forests,objectively evaluating the contribution of Eucalyptus plantation forests to increasing timber supply and enhancing forest carbon sink capacity in China,and providing a scientific basis for formulating sustainable management policies.【Method】In this study,we collected the sample plot data from 9 national forest inventories(NFIs)during 1973—2018,China forest-land database map in 2003 and 2016,as well as climate and elevation data,and analyzed the dynamic changes in the spatial distribution of Eucalyptus plantation forests and continuously tracked the changes of Eucalyptus in fixed sample plots,and quantitatively evaluated Eucalyptus in China based on the accumulation data of eucalyptus fixed sample plots for 5 periods of 25 years(from 1994 to 2018).The productivity,carbon accumulation capacity,and abandonment rate of Eucalyptus in China were quantitatively evaluated based on the accumulation of Eucalyptus in fixed sample plots for five periods of 25 years.【Result】The results showed that regions with annual mean air temperature of 19-21℃,annual precipitation of 1400-1600 mm,and elevation of 0-300 m above sea level suit the growth of Eucalyptus plantations best.The average annual productivity of Eucalyptus trees nationwide generally ranges from 4.14 to 8.57 m^3·hm^(-2)a^(-1),which is higher in four provinces of Hainan,Guangdong,Guangxi,and Fujian,with 2-3-year-old Eucalyptus forests approaching 40 m^3·hm^(-2)a^(-1);according to the 9th inventory(2014—2018)data,the average annual carbon sequestration per hectare of Eucalyptus was 5.29 t·hm−2a^(−1),which was 2.95 and 2.18 times higher than that of fast-growing tree species,horsetail pine and fir plantations in the same region.Despite the low harvesting age of Eucalyptus and the fact that 46%of the harvesti
作者
张煜星
王雪军
Zhang Yuxing;Wang Xuejun(Academy of Forest and Grassland Inventory and Planning,National Forestry and Grassland Administration, Beijing 100714;Forest Resource Management Department,National Forestry and Grassland Administration ,Beijing 100714)
出处
《林业科学》
EI
CAS
CSCD
北大核心
2023年第3期54-64,共11页
Scientia Silvae Sinicae
基金
国家重点研发计划区域人工林资源遥感动态监测技术研究(2017YFD0600903)。
关键词
桉树
森林资源清查
地理分布
森林生产力
碳储量
碳汇能力
Eucalyptus plantations
national forest inventory(NFI)
geographical distribution
forest productivity
carbon storage
carbon sink capacity
