氮磷添加对杉木根叶分解残余物微生物群落结构及酶活性的影响  

Effects of nitrogen and phosphorus additions on microbial community structure and enzyme activity in root and leaf debris of Cunninghamia lanceolata

作　　者：王玉鑫 付晓莉[1] 王辉民[1,2] 戴晓琴 寇亮[1] 方向民[3] WANG Yuxin;FU Xiaoli;WANG Huimin;DAI Xiaoqin;KOU Liang;FANG Xiangmin(Qianyanzhou Ecological Research Station,Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;College of Resource and Environment,University of Chinese Academy of Sciences,Beijing 100049,China;School of Forestry,Jiangxi Agricultural University,Nanchang 330045,China)

机构地区：[1]中国科学院地理科学与资源研究所生态系统网络观测与模拟重点实验室千烟洲生态站,北京100101 [2]中国科学院大学资源与环境学院,北京100049 [3]江西农业大学林学院,南昌330045

出　　处：《生态学报》2021年第13期5408-5416,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金重点项目(41830646);江西省重点研发计划项目课题(20181ACH80006-01)。

摘　　要：为揭示根、叶分解残余物对生态系统养分循环相关过程的影响,研究了分解第3年杉木根残余物(凋_(R))和叶残余物(凋_(L))中的微生物群落结构(环丙基脂肪酸/前体结构,Cy/pre;单不饱和脂肪酸/饱和脂肪酸,Mono/sat;真菌/细菌,F/B;革兰氏阳性菌/革兰氏阴性菌,G^(+)/G^(-))、酶活性(β-葡萄糖苷酶,βG;β-N-乙酰氨基葡糖苷酶,NAG;酸性磷酸酶,AP)、化学元素含量及计量比对氮磷添加的响应。结果表明:(1)与凋_(R)相比,凋_(L)中的Cy/pre、F/B、G^(+)/G^(-)低,Mono/sat高。氮磷添加对分解残余物微生物群落结构影响不显著。(2)与凋_(R)相比,凋_(L)中的βG和NAG活性高、βG/AP大。氮磷添加抑制了AP活性,提高了βG/NAG及βG/AP。且氮磷添加对凋_(R)的AP活性抑制作用更强,对凋_(L)的βG/NAG提升幅度更大。(3)分解残余物中的Mono/sat、G+/G、F/B分别与锰含量、磷/钙、氮含量正相关;AP、βG/NAG分别与氮/磷、磷/铁正相关;βG/AP、NAG、βG分别与氮/锰、磷/镁、氮/钙负相关。表明根、叶分解残余物仍可对生态系统养分循环相关过程产生不同影响,考虑分解残余物类型可提高全球变化背景下生态系统养分循环过程预报精度。Root and leaf litters are two important litter sources in ecosystems,providing carbon sources and nutrients for microorganisms.The decompositions of root and leaf litters are highly sensitive to the environmental availability of nutrients.The simultaneous deposition of nitrogen and phosphorus is one of the most critical challenges in ecosystems worldwide.Changes of nitrogen and phosphorus inputs can affect both the decomposition rates of root and leaf litter and other responses of the ecosystem.The long⁃term patterns of mass loss during leaf and root litter decomposition are well documented,but the responses of microbial community structure and enzyme activity in root and leaf debris to the simultaneous deposition of exogenous nitrogen and phosphorus are not known.Understanding the influence of simultaneous inputs of exogenous nitrogen and phosphorus on the microbial community structure and enzyme activity in root and leaf debris can help us to precisely predict shifts in ecosystem processes in nitrogen and phosphorus deposition enriched regions.We investigated the responses of microbial community structure(cyclopropyl fatty acids/precursor structure,Cy/pre;monounsaturated fatty acids/saturated fatty acid,Mono/sat;fungus/bacteria,F/B;Gram⁃positive bacteria/Gram⁃negative bacteria,G^(+)/G^(-)),enzyme activity(glucosidase,βG;β⁃N⁃Acetylglucosaminidase,NAG;acid phosphatase,AP),chemical element content and stoichiometry in root and leaf debris(3 years after decomposition)of Cunninghamia lanceolata to nitrogen and phosphorus additions.Results showed that Cy/pre,F/B,G^(+)/G^(-)were lower and Mono/sat was higher in the leaf debris than those in the root debris.However,nitrogen and phosphorus additions had no significant effect on the microbial community structure of the debris.The leaf debris had higherβG and NAG activity andβG/AP compared with the root debris.Nitrogen and phosphorus additions decreased the AP activity and increasedβG/NAG andβG/AP.Moreover,nitrogen and phosphorus additions resulted in a gr

关 键 词：氮磷添加 微生物群落结构 酶活性 化学计量 凋落物分解 

分 类 号：S714[农业科学—林学]