根系-菌根-土壤微生物对毛竹林土壤氮矿化过程的贡献  

Contribution of roots-mycorrhizae-free-living microorganisms to soil nitrogen mineralization in moso bamboo forest

作　　者：包涛涛 李丝雨 王一 蒋文婷 蔡延江 孙连鹏 栾军伟 BAO Taotao;LI Siyu;WANG Yi;JIANG Wenting;CAI Yanjiang;SUN Lianpeng;LUAN Junwei(State Key Laboratory of Subtropical Forest Cultivation,College of Environment and Resources,Zhejiang A&F University,Hangzhou 311300,China;Institute of Bamboo and Rattan Resources and Environment,International Centre for Bamboo and Rattan,National Forestry and Grassland Administration/Beijing Key Laboratory of Bamboo and Rattan Science and Technology,Beijing 100102,China;Sanya Research Base,International Center for Bamboo and Rattan,Sanya 572022,Hainan,China)

机构地区：[1]浙江农林大学省部共建亚热带森林培育国家重点实验室,浙江农林大学环境与资源学院,杭州311300 [2]国际竹藤中心竹藤资源与环境研究所,国家林业和草原局/北京市共建竹藤科学与技术重点实验室,北京100102 [3]国际竹藤中心三亚研究基地,海南三亚572022

出　　处：《生态学杂志》2024年第5期1234-1242,共9页Chinese Journal of Ecology

基　　金：国家自然基金面上项目(31971461);十四五重点研发计划课题(2021YFD2200405)和(2021YFD2200403);中央公益性科研院所基本科研业务费学科发展项目(1632019006和1632021023)资助。

摘　　要：土壤氮矿化是土壤氮素循环的关键过程之一,决定了土壤的供氮能力。然而,有关植物根系、共生菌根菌丝体和土壤微生物等不同生物因素对土壤氮矿化的贡献缺乏了解。本研究以浙江省庙山坞自然保护区毛竹(Phyllostachys edulis)林为对象,利用阴阳离子树脂芯原位培养技术研究毛竹林土壤氮矿化过程,并结合不同网孔大小(1.45 mm:允许所有组分进入,53μm:排除根但允许菌丝进入,1μm:排除根和菌丝进入)微宇宙进一步区分根系、菌丝体和土壤微生物的作用。结果表明:(1)通过不同孔径微宇宙装置处理,53μm微宇宙较1.45 mm微宇宙对根系的排除效果达到了100%,1μm微宇宙较53μm微宇宙对菌丝的排除效果达到了70%;(2)不同生物组分参与土壤氮循环过程主要改变了土壤氨化速率,增加根系参与土壤氮循环过程后(1.45 mm微宇宙)土壤净氨化速率较排除根系参与时(53μm微宇宙)低36.58%;而不同孔径微宇宙装置间土壤净硝化速率、净矿化速率无显著差异;(3)1.45 mm微宇宙中土壤亮氨酸氨基肽酶(LAP)和酚氧化物酶(POX)较53μm微宇宙分别高27.59%和61.54%,可能是土壤净氨化速率降低的主要原因。本研究量化了根际(根系、菌根真菌)介导驱动对毛竹林土壤氮矿化过程贡献,土壤微生物是影响毛竹林土壤净硝化作用和矿化作用的重要生物因子,而根系和共生菌根则在土壤净氨化作用中发挥重要作用。As a key process of soil nitrogen(N)cycle,soil N mineralization drives N supply capacity of soil.However,the contribution of different biological factors such as roots,mycorrhizal mycelia,and asymbiotic microorganisms to soil N mineralization is poorly understood.In this study,we examined soil N mineralization of moso bamboo forest(Phyllostachys edulis)in Miaoshanwu Nature Reserve in Zhejiang Province,employing in situ incubation technique with anionic and cationic resin cores.Combined with different mesh sizes(1.45 mm:allowing all components to enter;53μm:excluding roots but allowing mycelium to enter;and 1μm:excluding roots and mycelium to enter while only allowing free-living microorganisms to enter),the microcosm further distinguished the effects of roots,mycelium and free-living microorganisms.The results showed that:(1)In the treatments of different mesh size microcosms,the exclusion effect of 53μm microcosm on roots reached 100%compared with 1.45 mm microcosm,and the exclusion effect of 1μm microcosm on hyphae reached 70%compared with 53μm microcosm.(2)The participation of different biological components in the soil N cycling mainly changed soil ammonification rate.Soil net ammonification rate after root system participated in the soil N cycle process(1.45 mm microcosm)was 36.58%lower than that when the roots were excluded(53μm microcosm).However,there was no significant difference in soil net nitrification rate and net mineralization rate among microcosm devices with different mesh sizes.(3)The soil leucine aminopeptidase(LAP)and phenoloxidase(POX)activities were significantly higher in the 1.45 mm microcosm compared to the 53μm microcosm by 27.59%and 61.54%,respectively,which in turn led to a decrease in soil net ammonification rate.This study quantified the contribution of rhizosphere(root,mycorrhizal mycelia)-mediated soil N mineralization process of bamboo forest.Free-living microorganisms are important biological factors affecting soil net nitrification and mineralization,while roots and mycor

关 键 词：竹林 土壤氮循环 根际 菌根真菌 净硝化速率 净氨化速率 净矿化速率 

分 类 号：S714[农业科学—林学]