不同水分含量下黑土硝化反硝化微生物群落结构的变化  

Variation of nitrification and denitrification microbial community structures in black soil under different moisture content

作　　者：丛兢兢 马君玲[1] 李顺和 高威 鲍雪莲[3] 朱雪峰 解宏图[3] 王连峰[1] CONG Jing-jing;MA Jun-ling;LI Shun-he;GAO Wei;BAO Xue-lian;ZHU Xue-feng;XIE Hong-tu;WANG Lian-feng(School of Environment and Chemical Engineering,Dalian Jiaotong University,Dalian,Liaoning 116028,China;Key Laboratory of Agro-ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha,Hunan 410125,China;Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang,Liaoning 110016,China)

机构地区：[1]大连交通大学环境与化学工程学院,辽宁大连116028 [2]中国科学院亚热带农业生态研究所亚热带农业生态重点实验室,湖南长沙410125 [3]中国科学院沈阳应用生态研究所,辽宁沈阳110016

出　　处：《植物营养与肥料学报》2023年第8期1400-1410,共11页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金项目(41471205,41977048);黑土地保护与利用科技创新工程专项(XDA28090100);辽宁省“百千万人才工程”项目(2019B39)。

摘　　要：【目的】阐明土壤水分含量的变化对土壤硝化与反硝化微生物数量的影响,揭示土壤微生物群落结构对土壤水分含量的响应规律,为黑土区农田合理水分管理提供参考。【方法】依托长期定位试验平台,采集典型黑土区表层土壤样品进行室内微宇宙试验,设置4个土壤水分含量梯度(40%WHC、60%WHC、80%WHC和100%WHC)模拟土壤湿度环境,土壤样品在(25±1)℃下连续培养7天后,采用实时荧光定量q-PCR和高通量测序技术,分析黑土硝化与反硝化微生物数量,揭示不同土壤水分含量下黑土微生物群落结构的变化规律。【结果】土壤水分对农田黑土硝化与反硝化微生物数量影响显著。硝化微生物AOA基因拷贝数在60%WHC下最低,随着土壤水分含量的升高而显著增加(P<0.05)。AOB基因拷贝数变化随土壤水分状况的变化由多到少依次为100%WHC、60%WHC、80%WHC和40%WHC。反硝化微生物nirS和nosZ基因拷贝数均随土壤含水量的升高而增加,在土壤含水量为100%WHC条件下均达到最高值,分别是40%WHC条件下的38和2.7倍。高通量测序及分析结果表明,不同土壤水分状况下土壤微生物群落结构发生明显分异,微生物物种组间差异分析发现,不同土壤水分状况微生物群落组成差异显著,80%WHC处理条件下土壤微生物群落的物种丰富度和多样性较高,而100%WHC处理条件下土壤微生物群落的多样性较低。低土壤水分(40%WHC和60%WHC)状况下土壤中的优势微生物属为难培养的RB41和硝化螺菌(Nitrospira),高土壤水分(80%WHC和100%WHC)状况下为根瘤杆菌(Rhizobacter)、假单胞菌(Pseudomonas)和黄色土源菌(Flavisolibacter)。土壤水分含量与优势微生物类群的相关分析结果表明,变形菌门(Proteobacteria)与土壤水分含量呈现极强的正相关关系,根瘤杆菌属和假单胞菌属与土壤水分含量呈显著正相关关系。【结论】较低的土壤水分含量增加硝化微生物丰度,�【Objectives】The abundance of nitrification and denitrification microorganisms under different soil moistures was studied to reveal the response of soil microbial community structure to soil moisture content,and serve the water management of farmland in black soil area.【Methods】The tested soil was collected from a long-term experiment station in a typical black soil.Microcosmic controlled laboratory culture experiment was conducted and soil samples were loaded into tubes,four soil moisture treatments were setup to simulate field soil moisture environments of 40%WHC,60%WHC,80%WHC and 100%WHC.After incubated for 7 days at(25±1)℃,the abundance of nitrification and denitrification microorganisms in soils was determined using real-time fluorescence quantitative q-PCR and high-throughput sequencing technology,to reveal the change of microbial community structure under different soil moisture contents.【Results】Soil moisture significantly affected the abundance of nitrification and denitrification microorganisms in black soil.For nitrification microorganisms,the copy number of AOA gene was the lowest at 60%WHC,and then increased significantly with the increase of soil moisture.The AOB gene copy number was in descending order of 100%WHC,60%WHC,80%WHC and 40%WHC.For denitrification microorganisms the copy number of nirS and nosZ genes increased with the increase of soil water content.The highest values were under 100%WHC,38 and 2.7 times of those under 40%WHC.The results of high-throughput sequencing analysis showed that soil microbial community structure and composition changed significantly under different water conditions.The species richness and diversity of soil microbial community under 80%WHC treatment were relatively high,while the diversity of soil microbial community under 100%WHC treatment was relatively low.RB41 and Nitrospira were the dominant genera under 40%WHC and 60%WHC,while Rhizobacter,Pseudomonas and Flavisolibacter were the dominant genera under 80%WHC and 100%WHC.Proteobacteria had a str

关 键 词：黑土 水分含量 实时荧光定量q-PCR 高通量测序 硝化微生物 反硝化微生物 

分 类 号：S152.7[农业科学—土壤学]