福建省杉木人工林土壤亚硝酸盐还原基因丰度及其主要环境驱动因子  

Abundance of nitrite reducing genes and their primary driving factors in soilsof Chinese fir plantation from Fujian Province

作　　者：邓米林 郑勇 张晗烁 韩风毅 杨浩 贺纪正[1,2] 林永新 DENG Milin;ZHENG Yong;ZHANG Hanshuo;HAN Fengyi;YANG Hao;HE Jizheng;LIN Yongxin(Cultivation Base of State Key Laboratory for Subtropical Mountain Ecology,Fuzhou 350007;School of Geographical Sciences,Fujian Normal University,Fuzhou 350007)

机构地区：[1]湿润亚热带山地生态国家重点实验室培育基地,福州350007 [2]福建师范大学地理科学学院,福州350007

出　　处：《环境科学学报》2024年第2期406-412,共7页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.42077041,31971447)。

摘　　要：杉木在我国南方亚热带地区被大面积种植,导致土壤性质发生巨大变化.为揭示福建省杉木人工林土壤中亚硝酸盐还原基因(nirS和nirK)的分布特征及其主要环境驱动因子,本研究选取福建省9个主要林场的杉木人工林土壤为研究对象,使用荧光定量PCR分析了nirS和nirK基因丰度,同时测定反硝化潜势.结果表明:福建省杉木人工林土壤理化性质呈较大的变异特征,其中,pH值为4.02~5.05,为典型的酸性森林土壤.各采样点杉木人工林土壤nirS丰度均显著高于nirK,表明nirS在酸性杉木人工林土壤中占主导.随机森林和逐步回归分析均表明,土壤含水率是影响nirS基因丰度最主要的环境因子,而nirK基因丰度则主要受土壤pH值调控.相关性分析表明,nirS和nirK基因丰度分别与土壤含水率和pH值呈显著正相关.此外,土壤反硝化潜势与SOC、DOC、TN、NO_(3)^(-)、MC等环境因子呈显著相关,同时与nirK丰度呈显著正相关,但与nirS丰度无显著相关.综上,福建省杉木人工林土壤nirS和nirK基因丰度存在较大空间变异,土壤含水率和pH值分别是其主要环境驱动因子.Cunninghamia lanceolata(Chinese fir)is widely planted in subtropical regions of south China,resulting in substantial alteration of soil properties.In order to reveal the distribution patterns of two nitrite reducing genes(nirS and nirK)and their primary driving factors in soils of Chinese fir plantation in Fujian Province,soil samples from nine major forest farms of Chinese fir plantation in Fujian Province were collected to determine the abundance of nirS and nirK genes using real-time quantitative PCR and the potential denitrification rate.Results showed that soil properties varied substantially in Chinese fir plantations in Fujian Province.The pH values range from 4.02 to 5.05,being typical acidic forest soils.The abundance of nirS gene was significantly higher than that of nirK in the soils of all sampling points,indicating that nirS dominated in the acidic Chinese fir plantation soils.Random forest and stepwise regression analysis showed that soil moisture content was a primary factor regulating the abundance of nirS gene,whereas the abundance of nirK gene was mainly regulated by soil pH.Correlation analysis showed that nirS and nirK gene abundances were positively correlated with soil moisture content and pH,respectively.Moreover,soil potential denitrification rate was positively associated with soil environmental factors,such as SOC、DOC、TN、NO_(3)^(-)and MC.It also positively associated with the abundance of nirK,rather than nirS.Taken together,the abundance of nirS and nirK gene varies substantially in the soils from Chinese fir plantation in Fujian Province,with moisture content and pH as the key environmental driving factor,respectively.

关 键 词：杉木人工林 反硝化 反硝化潜势 nirS NIRK 

分 类 号：S154.36[农业科学—土壤学]