摘要
发展桉树(Eucalyptus spp.)人工林对保障国家木材安全,应对全球气候变化以及推动林业高质量发展具有重要意义。本研究在桉树生态营林试验示范基地开展,采用随机区组试验设计,以生态营林方式下的尾巨桉纯林(Pure Eucalyptus urophylla×E.grandis plantation,PE)、尾巨桉×降香黄檀混交林(Mixed E.urophylla×E.grandis and Dalbergia odorifera plantation,MED)、尾巨桉×红锥混交林(Mixed E.urophylla×E.grandis and Castanopsis hystrix plantation,MEC)、尾巨桉×望天树混交林(Mixed E.urophylla×E.grandis and Parashorea chinensis plantation,MEP)为研究对象,并以传统营林方式下的尾巨桉纯林作为对照(CK),探究生态营林对表层土壤有机碳组分和酶活性的影响。结果表明:与传统营林方式下的尾巨桉纯林相比,生态营林林分均能显著提高土壤有机碳(SOC)、颗粒态有机碳(POC)、矿物结合态有机碳(MAOC)和难氧化有机碳(NOC)含量,同时显著提高POC占SOC的比例(P<0.05)。此外,生态营林林分显著提高了土壤全氮(TN)含量,其中以尾巨桉×降香黄檀混交林增幅最大。在土壤酶活性方面,生态营林林分增强了N-乙酰-β-D-氨基葡萄糖苷酶(NAG)和酸性磷酸酶(ACP)的活性,但降低了亮氨酸氨基肽酶(LAP)的活性。通过土壤酶化学计量分析发现,桉树人工林土壤微生物生长代谢活动存在磷限制现象,且传统营林林分的磷限制更为严重。冗余分析表明,TN、LAP和ACP是影响表层土壤有机碳组分含量及其占SOC比例的主要因子。综上所述,生态营林方式通过提高POC、MAOC含量来促进土壤有机碳的稳定积累,同时增强NAG和ACP活性。其中,桉树与乡土树种混交能显著促进土壤氮素养分积累,并维持较高的土壤全磷(TP)和速效磷(AP)含量,这不仅有效缓解了土壤微生物的磷限制,还显著改善了林分土壤质量并促进林木生长。
The development of Eucalyptus spp.plantations is essential for ensuring national timber security,responding to global climate change,and achieving high-quality forestry development.A randomized block design was adopted to conduct the field trial in the eco-silviculture demonstration base of Eucalyptus spp.plantations.The Pure Eucalyptus urophylla×E.grandis plantation(PE),Mixed E.urophylla×E.grandis and Dalbergia odorifera plantation(MED),Mixed E.urophylla×E.grandis and Castanopsis hystrix plantation(MEC),and Mixed E.urophylla×E.grandis and Parashorea chinensis plantation(MEP)under eco-silviculture regime were taken as the research subjects,with pure E.urophylla×E.grandis plantation under the conventional management regime as the control(CK).The effects of eco-silviculture on the organic carbon fractions and enzyme activities in the surface soil were studied.The results showed that compared with the pure Eucalyptus spp.plantation under the conventional forest management regime,the stands under eco-silviculture regime presented significantly increased content of Soil Organic Carbon(SOC),Particulate Organic Carbon(POC),Mineral-Associated Organic Carbon(MAOC),and Noble Organic Carbon(NOC)and enzyme activities in the surface soil,as well as increased proportion of POC in SOC(P<0.05).Furthermore,eco-silviculture significantly increased the content of Total Nitrogen(TN)in soil,with the largest increase observed in E.urophylla×E.grandis and Dalbergia odorifera mixed plantation.Furthermore,eco-silviculture enhanced the activities of N-Acetyl-β-D-Glucosaminidase(NAG)and Acid Phosphatase(ACP),while decreasing the Leucine Aminopeptidase(LAP)activity.The stoichiometric analysis of enzyme activities showed that the soil microbial growth and metabolic activity in Eucalyptus spp.plantations was limited by phosphorus,which was more serious in the Eucalyptus spp.plantations under the conventional management regime.Redundancy analysis revealed that TN,LAP and ACP were the primary influencing factors of SOC fractions and their proportions in SOC.In summary,eco-silviculture promoted the stable accumulation of SOC by increasing POC and MAOC content and enhancing NAG and ACP activities.The mixing of Eucalyptus and native tree species can obviously promote the accumulation of soil nitrogen and maintain high content of Total Phosphorus(TP)and Available Phosphorus(AP),which is conducive to alleviating the phosphorus restriction of soil microbial growth,improving soil quality,and facilitating tree growth.
作者
杨婷
周晓果
温远光
邓少虹
陈静文
陈金磊
许峻模
吴衍霖
陈秋海
孙冬婧
黄勇杰
喻素芳
YANG Ting;ZHOU Xiaoguo;WEN Yuanguang;DENG Shaohong;CHEN Jingwen;CHEN Jinlei;XU Junmo;WU Yanlin;CHEN Qiuhai;SUN Dongjing;HUANG Yongjie;YU Sufang(School of Forestry,Guangxi University,Nanning,Guangxi,530004,China;Institute of Eco-Environment Research,Guangxi Academy of Sciences,Nanning,Guangxi,530007,China;Guangxi Youyiguan Forest Ecosystem Research Station,Pingxiang,Guangxi,532600,China)
出处
《广西科学》
北大核心
2025年第3期426-438,共13页
Guangxi Sciences
基金
国家自然科学基金项目(32160358,32360284)
广西自然科学基金项目(2023GXNSFBA026328,2024GXNSFBA010328)资助。
关键词
土壤有机碳组分
颗粒态有机碳
矿物结合态有机碳
生态营林
桉树人工林
soil organic carbon fractions
particulate organic carbon
mineral-associated organic carbon
eco-silviculture
Eucalyptus spp.plantation
