湿地土壤微生物功能多样性及碳氮组分对长期氮输入的响应  

Response of soil microbial functional diversity and soil carbon and nitrogen components to long⁃term nitrogen input in wetlands

作　　者：李孟婷 宋艳宇[2] 宫超[2] 高思齐 刘桢迪 朱梦圆 袁佳宝 刘吉平[1] LI Mengting;SONG Yanyu;GONG Chao;GAO Siqi;LIU Zhendi;ZHU Mengyuan;YUAN Jiabao;LIU Jiping(College of Geographical Sciences and Tourism,Jilin Normal University,Siping 136000,China;Key Laboratory of Wetland Ecology and Environment,Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun 130102,China;College of Resources and Environment,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]吉林师范大学地理科学与旅游学院,四平136000 [2]中国科学院东北地理与农业生态研究所中国科学院湿地生态与环境重点实验室,长春130102 [3]中国科学院大学资源与环境学院,北京100049

出　　处：《生态学报》2023年第20期8544-8555,共12页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(41871090);吉林省科技发展计划项目(20210101091JC);“一带一路”国际科学组织联盟项目(ANSO⁃PA⁃2020⁃14)。

摘　　要：氮输入对湿地生态系统碳氮循环具有重要影响,研究湿地土壤微生物功能多样性及碳氮组分对氮输入的响应,对于明确湿地土壤碳氮循环微生物驱动机制具有重要意义。依托长期野外氮输入模拟试验,利用Biolog⁃ECO微平板技术,分析不同浓度氮输入:N1(6 g N m^(-2)a^(-1))、N2(12 g N m^(-2)a^(-1))和N3(24 g N m^(-2)a^(-1))对湿地土壤表层(0—15 cm)和亚表层(15—30 cm)微生物碳源代谢活性、功能多样性和碳氮组分的影响。结果表明:N2处理显著提高了亚表层土壤微生物碳源代谢活性和McIntosh指数,N3处理显著降低了表层土壤微生物Shannon指数和Shannon⁃evenness指数。随氮输入浓度增加湿地表层土壤微生物对糖类的利用率显著降低,N3处理表层土壤微生物对胺类的利用率以及亚表层土壤微生物对醇类的利用率显著提高。N1处理显著提高了湿地表层土壤全氮和微生物量碳含量;N2、N3处理显著提高了土壤铵态氮、硝态氮含量;N3处理显著降低了土壤pH值。湿地土壤pH、总碳、溶解性有机碳含量是影响微生物碳源代谢活性和功能多样性的重要因素,土壤溶解性有机碳、铵态氮、全氮含量、含水率是影响微生物碳源利用变化的主要因子。Wetland is a huge reservoir of carbon and nitrogen and plays an important role in the global carbon and nitrogen cycling.Soil microorganisms are the main medium for organic matter decomposition and nutrient cycle.Nitrogen input has significant effects on soil nutrient,carbon and nitrogen cycling as well as soil microbial community structure and function.Therefore,to better understand the microbial driving mechanism of carbon and nitrogen cycling in wetland soil,it is crucial to clarify the characteristics of soil microbial functional diversity as well as the carbon and nitrogen components under nitrogen input.The effects of different nitrogen input concentrations,including N1(6 g N m^(-2)a^(-1)),N2(12 g N m^(-2)a^(-1)),and N3(24 g N m^(-2)a^(-1)),on microbial carbon source metabolic activities,functional diversity,and carbon and nitrogen components in the surface(0—15 cm)and subsurface(15—30 cm)of wetland soil were examined using Biolog⁃ECO microplate technology based on long⁃term field nitrogen input simulation experiment.The results showed that the metabolic activity of soil microbial carbon source increased gradually with the extension of culture time under different nitrogen input treatments.The Shannon index,Shannon⁃Evenness index,and McIntosh index were significantly higher in surface soil than in subsurface soil under CK treatment.N3 treatment significantly decreased the microbial Shannon index and Shannon⁃Evenness index in surface soil,while N2 treatment significantly increased the microbial carbon source metabolic activity and McIntosh index in subsurface soil.There were differences in the utilization capacity and preference of soil microorganisms with different nitrogen concentrations.With the increase of nitrogen input concentration,the utilization rate of carbohydrates by microorganisms in wetland surface soil significantly decreased,while the utilization rates of amines and phenolic compounds by microorganisms in surface and subsurface soil were significantly increased under N3 treatment.

关 键 词：湿地 氮输入 Biolog⁃ECO 碳源利用 土壤微生物多样性 

分 类 号：S154.3[农业科学—土壤学]