氮添加对巴音布鲁克高寒湿地土壤微生物量和酶活性的影响  

Effects of nitrogen addition on soil microbial biomass and enzymatic activity in Bayinbuluk alpine wetland

作　　者：胡洋 丛孟菲 陈末 买迪努尔·阿不来孜 愚广灵 申志博 杨再磊 朱新萍[1,3] 贾宏涛 HU Yang;CONG Mengfei;CHEN Mo;MAIDINUER Abulaizi;YU Guangling;SHEN Zhibo;YANG Zailei;ZHU Xinping;JIA Hongtao(College of Resources and Environment,Xinjiang Agricultural University,Urumqi 830052,China;College of Grassland Science,Xinjiang Agricultural University,Urumqi 830052,China;Xinjiang Key Laboratory of Soil and Plant Ecological Processes,Urumqi 830052,China)

机构地区：[1]新疆农业大学资源与环境学院,乌鲁木齐830052 [2]新疆农业大学草业学院,乌鲁木齐830052 [3]新疆土壤与植物生态过程重点实验室,乌鲁木齐830052

出　　处：《生态学报》2022年第13期5328-5339,共12页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31560171,31960258)。

摘　　要：随着全球氮沉降速率的快速增加,已对陆地生态系统微生物群落活性和代谢产生了深刻的影响。因此迫切需要了解全球气候变化敏感区土壤中微生物量和酶活性对氮添加的响应。为此,以中亚干旱区巴音布鲁克高寒湿地为研究对象,在保护良好的高寒湿地选择沼泽(S)、沼泽草甸(SM)和草甸(M)3种湿地类型布设野外原位氮添加试验(施氮浓度分别为0、8、16 kg N hm^(-2) a^(-1)),探究短期氮添加对土壤微生物生物量碳(MBC)、微生物生物量氮(MBN)、微生物生物量碳/氮(MBC/MBN)、微生物商(QMB)、土壤蛋白酶、脲酶、碱性磷酸酶、H_(2)O_(2)酶和蔗糖酶活性的影响。结果表明:(1)高寒湿地不同湿地类型土壤微生物量和酶活性存在显著差异,其中SM土壤MBC、MBN、MBC\N、QMB较S和M区高,对酶活性而言,SM和M区土壤蛋白酶和碱性磷酸酶活性较高,M区H_(2)O_(2)酶和脲酶活性较高。(2)氮添加显著增加了3种湿地类型中土壤MBC和MBN,其中MBC增加了7.00%—119.00%,MBN增加了8.03%—38.26%。氮添加仅显著增加了S和SM区土壤MBC/N和QMB(增加了24.68%—113.10%),但抑制了M区土壤MBC/N和QMB(抑制了8.93%—10.36%)。(3)氮添加显著增加了3种湿地类型土壤中脲酶、蛋白酶和H_(2)O_(2)酶活性,分别增加了7.25%—59.63%、4.71%—58.55%和34.70%—157.27%。但是氮添加对土壤碱性磷酸酶活性无显著影响。对蔗糖酶而言,N1处理增加了S区土壤蔗糖酶活性(增加了58.58%),而N2处理显著降低了22.72%。氮添加对SM和M区蔗糖酶活性无显著影响。(4)结构方程模型的结果显示,氮添加直接增加了土壤微生物量和酶活性。而随着湿地类型的变化(S⁃SM⁃M)直接和间接(通过pH)增加了酶活性;湿地类型的变化还通过影响pH、有机碳和有效养分间接增加了土壤微生物量。总之,氮添加和湿地类型可直接或间接的影响着土壤微生物量和酶活性。其中,土壤pH和有机碳是微生物�With the rapid increase of global nitrogen deposition rate,it had a profound impact on the activity and metabolism of microbial community in the terrestrial ecosystem.Therefore,it is urgent to understand the response of soil microbial biomass and enzyme activity to nitrogen addition in the sensitive areas of global climate change.Therefore,taking Bayinbuluk alpine wetland in the arid region of the Central Asia as the research object,this study selected 3 types of well protected alpine wetlands:Swamp(S),Swamp meadow(SM)and Meadow(M),and arranged field in situ nitrogen addition experiments(nitrogen application concentrations are 0,8 and 16 kg N hm^(-2) a^(-1),respectively).The aim is to explore the effects of short-term nitrogen addition on soil microbial biomass carbon(MBC),microbial biomass nitrogen(MBN),microbial biomass carbon/nitrogen(MBC/MBN),microbial quotient(QMB),soil protease,urease,alkaline phosphatase,H_(2)O_(2) enzyme and sucrase activities.Results showed that:(1)there were significant differences in soil microbial biomass and enzyme activities among different wetland types in alpine wetland.The MBC,MBN,MBC/N and QMB in the SM were higher than those in S and M.For enzyme activities,soil protease and alkaline phosphatase activities in the SM and M were higher,and H_(2)O_(2) enzyme and urease activities in M were higher.(2)Nitrogen addition significantly increased soil MBC and MBN in the 3 wetland types,in which MBC increased by 7.00%—119.00%and MBN increased by 8.03%—38.26%.Nitrogen addition only significantly increased soil MBC/N and QMB in S and SM area(increased by 24.68%—113.10%),but inhibited soil MBC/N and QMB in M area(inhibited by 8.93%—10.36%).(3)Nitrogen addition significantly increased the activities of urease,protease and H_(2)O_(2) in the soil of the 3 areas,by 7.25%—59.63%,4.71%—58.55%,and 34.70%—157.27%,respectively.However,nitrogen addition had no significant effect on soil alkaline phosphatase activity.For sucrase,N1 treatment increased soil sucrase activity in the S area(

关 键 词：氮添加 高寒湿地 微生物量 酶活性 

分 类 号：S154[农业科学—土壤学]