摘要
本研究选择巨尾桉纯林(对照)、巨尾桉与杉木(桉杉)混交林、巨尾桉与福建柏(桉柏)混交林以及巨尾桉与杉木、福建柏(桉杉柏)混交林4种林分,将巨尾桉新鲜凋落桉树树皮放置于4种林分中,在540 d的分解周期内,每隔60 d回收一次分解袋,研究分解袋中残留凋落树皮的干重以及碳、氮、磷、纤维素和木质素含量,分析凋落桉树树皮的分解特征、主场效应以及养分释放动态及关键驱动因子。结果表明:混交林的凋落桉树树皮分解速率均显著高于桉树纯林,主场效应指数为负值,其中以桉杉混交林的分解最快,桉杉柏混交林次之,桉柏混交林略高于桉树纯林。3种混交林均促进了凋落桉树树皮分解过程中有机碳(C)、氮(N)、磷(P)的矿化及纤维素的降解,但对凋落桉树树皮木质素的分解影响较小,并伴随着C/N、C/P、N/P的下降和木质素/N的提升。在凋落桉树树皮分解过程中,有机碳和纤维素在主场与客场均表现为持续释放模式,N和P则呈现“释放-积累-释放”模式。养分残留量、化学计量比、难分解物含量共同解释了凋落桉树树皮分解变异的76.6%,其中,较高的C残留量会加速桉树树皮的分解,而较高的P残留率和C/N、N/P值会抑制分解。桉杉混交林对巨尾桉凋落桉树树皮的分解具有显著促进作用,建议未来桉树林林分结构改造时可优先考虑桉杉混交林。
Senesced bark litter of Eucalyptus collected from pure Eucalyptus plantation was placed in four stand types,including pure Eucalyptus urophylla plantation(control),E.urophylla-Cunninghamia lanceolata mixed plantation(Eucalyptus-Cunninghamia),E.urophylla-Fokienia hodginsii mixed plantation(Eucalyptus-Fokienia),and E.urophylla-C.lanceolata-F.hodginsii mixed plantation(Eucalyptus-Cunninghamia-Fokienia).During a 540-day decomposition period,litterbags were retrieved every 60 days to measure remaining dry mass and the contents of carbon(C),nitrogen(N),phosphorus(P),cellulose,and lignin.We analyzed decomposition characteristics,home-field advantage(HFA),nutrient release,and key drivers in mixed plantations.The results showed that decomposition rates in the mixed plantations were significantly higher than in the pure plantation,with negative HFA indices.Decomposition was fastest in the Eucalyptus-Cunninghamia mixed plantation,followed by the Eucalyptus-Cunninghamia-Fokienia mixed plantation and the Eucalyptus-Fokienia mixed plantation,which slightly exceeded the pure plantation.The three Eucalyptus-conifer mixed plantations promoted the mineralization of C,N,P,and the degradation of cellulose during bark litter decomposition,but had little effect on lignin degradation,accompanied by decreases in C/N,C/P,N/P and an increase in lignin/N.During the decomposition process,C and cellulose showed a continuous release pattern in both home and away fields,while N and P exhibited a“release-accumulation-release”pattern.Nutrient remaining amounts,stoichiometric ratios,and recalcitrant compound contents collectively explained 76.6%of the variation in bark litter decomposition.Higher C remaining amount is positively related with decomposition,while higher P remaining rate,C/N,and N/P negatively related with decomposition.The Eucalyptus-Cunninghamia mixed plantation significantly enhanced the decomposition of Eucalyptus bark litter.In future structural transformations of Eucalyptus plantations,it is recommended that Eucalyptus-Cunninghamia mixed plantation be prioritized.
作者
康婷婷
钟全林
梁锋娜
杨彬峰
徐朝斌
程栋梁
姚舒舒
赖雁南
KANG Tingting;ZHONG Quanlin;LIANG Fengna;YANG Binfeng;XU Chaobin;CHENG Dongliang;YAO Shushu;LAI Yannan(College of Geographical Sciences,Fujian Normal University,Fuzhou 350007,China;State Key Laboratory Breeding Base of Humid Subtropical Mountain Ecology,Fuzhou 350007,China;Fujian Province Key Laboratory of Plant Ecophysiology,Fujian Normal University,Fuzhou 350007,China)
出处
《应用生态学报》
北大核心
2025年第8期2325-2334,共10页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(32371859,31971643,32071555)
中央财政项目(闽2023TG29)
福建省科技厅中央引导地方专项(2024L3009)
福建省科技厅产学合作项目(2023N5006)
福建省科技厅重点项目(2021FKJ29,2023FKJ29,2024FKJ26)资助。
关键词
凋落桉树树皮分解
主场效应
养分释放
桉针混交林
亚热带
Eucalyptus bark litter decomposition
home-field advantage(HFA)
nutrient release
Eucalyptus-conifer mixed plantation
subtropical zone
