土壤盐渍化对稀有和常见细菌群落结构和功能的影响  

Effects of Soil Salinization on the Structure and Function of Rare and Common Bacteria

作　　者：林力涛 刘煜杰[1] 冯文婷 王玉刚[3,4] 张超 马斌 韩风 王龙龙 耿建阳 李福杰 LIN Litao;LIU Yujie;FENG Wenting;WANG Yugang;ZHANG Chao;MA Bin;HAN Feng;WANG Longlong;GENG Jianyang;LI Fujie(Center for Ecological Civilization Research,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;School of Grassland Science,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Desert and Oasis Ecology,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China;Fukang Station of Desert Ecology,Chinese Academy of Sciences,Fukang 831505,China;Urumqi Comprehensive Survey Center on Natural Resources,Urumqi 830057,China;Field Observation and Research Station of Water Resources and Ecological Effect in Lower Reaches of Tarim River Basin,China Geological Survey,Urumqi 830057,China)

机构地区：[1]中国环境科学研究院生态文明理论研究中心,北京100012 [2]北京林业大学草业与草原学院,北京100083 [3]中国科学院新疆生态与地理研究所,荒漠与绿洲生态国家重点实验室,新疆乌鲁木齐830011 [4]中国科学院新疆阜康荒漠生态系统国家野外科学观测研究站,新疆阜康831505 [5]中国地质调查局乌鲁木齐自然资源综合调查中心,新疆乌鲁木齐830057 [6]自然资源部塔里木河流域下游水资源与生态效应野外科学观测研究站,新疆乌鲁木齐830057

出　　处：《环境科学研究》2024年第10期2126-2137,共12页Research of Environmental Sciences

基　　金：国家重点研究计划项目(No.2021YFE0114500);中国地质调查局项目(No.DD20220887);国家自然科学基金项目(No.42077023)。

摘　　要：土壤盐渍化是全球干旱区防护林长期固存的主要胁迫因子,影响着防护林细菌群落结构及其驱动的物质循环和养分活性,细菌群落由常见物种和稀有物种组成,为明晰二者在环境胁迫响应中的功能作用,该文以塔里木沙漠公路防护林长期咸水灌溉形成的土壤盐分梯度为研究系统,测定土壤细菌群落和土壤碳氮磷酶活性,使用0.01%相对丰度阈值法确定稀有物种和常见物种,使用酶多功能性和向量法表征土壤功能,探究稀有和常见细菌对盐渍化响应的敏感性及二者对土壤功能的驱动作用。结果表明:①防护林稀有细菌物种丰富度随盐分含量增加呈显著下降趋势(P<0.05);稀有细菌(ρ=0.293,P<0.01)和常见细菌群落组成(ρ=0.205,P<0.01)均受土壤盐分变化的影响,但稀有细菌群落组成呈现更大的变幅。②土壤细菌活性受磷而非氮元素的限制(向量角度>45°),随盐分含量增加,磷代谢/氮代谢功能呈显著下降(r=-0.190,P<0.05)的趋势,酶多功能性呈显著增加(r=0.253,P<0.01)的趋势。③常见细菌物种丰富度(r=0.173,P<0.05)及群落组成(r=0.181,P<0.05)显著提升了碳代谢功能(向量长度),群落组成显著改善了土壤酶多功能性(partial r=0.177,P<0.01)。研究显示,沙漠公路防护林稀有细菌而非常见细菌主导群落对盐渍化的响应,二者对土壤功能的调控路径存在差异,而常见细菌是土壤功能变化的主要驱动者。Soil salinization is a common stress on shelterbelts in arid regions around the world,which affects the cycling and maintenance of soil nutrients mediated by bacteria and threatens the stability of desert shelterbelt ecosystems.Bacterial communities consist of both common and rare species,but their roles in salinity stress responses remain unclear.The purpose of this study was to determine how rare and common bacteria respond to salinization,as well as the effects on soil function.Thus,soil bacterial community and carbon,nitrogen,and phosphorus-related enzyme activities along the salinity gradient in the Tarim Desert Highway shelterbelt formed by long-term saline irrigation were investigated.The rare and common bacteria were identified using the 0.01%relative abundance threshold method,and the soil function was characterized using the multifunctionality and vector methods.The results showed that:(1)The species richness of rare bacteria in the shelterbelts decreased significantly with soil salinity(P<0.05).Soil salinization significantly altered the community composition of rare bacteria(ρ=0.293,P<0.01)and common bacteria(ρ=0.205,P<0.01),with rare bacteria exhibiting greater variation.(2)Soil bacteria in the shelterbelts were limited by phosphorus but not nitrogen(vector angle>45°).As soil salinity increased,soil phosphorus/nitrogen cycling function(r=−0.190,P<0.05)and enzyme multifunctionality(r=0.253,P<0.01)decreased and increased,respectively.(3)The common bacteria were positively correlated with soil carbon cycle function(vector length)for species richness(r=0.173,P<0.05)and community composition(r=0.181,P<0.05),as well as soil enzyme multifunctionality(partial r=0.177,P<0.01)for community composition.The findings imply that the rare taxa,rather than common taxa,dominated the responses of the bacterial community in shelterbelts to salinization,and that the mechanisms of these two groups in shaping the soil function were different,with common bacteria acting as the primary driving force.

关 键 词：稀有物种 常见物种 土壤盐渍化 细菌群落 防护林 结构-功能关系 

分 类 号：X172[环境科学与工程—环境科学] S154[农业科学—土壤学]