农牧交错带草地生态系统N_(2)O通量对短期氮、磷添加的响应  

Responses of N_(2)O flux to short-term nitrogen and phosphorus addition in grassland ecosystem of agro-pastoral ecotone

作　　者：燕学东 陈晓鹏 郝杰[1,2,3] 刁华杰 李红玉 董宽虎 王常慧[1,2,3] YAN Xue-dong;CHEN Xiao-peng;HAO Jie;DIAO Hua-jie;LI Hongyu;DONG Kuan-hu;WANG Chang-hui(College of Grassland Science,Shanxi Agricultural University,Taigu,Shanxi 030801,China;Shanxi Key Laboratory of Grassland Ecological Protection and Native Grass Germplasm Innovation,Taigu,Shanxi 030801,China;Youyu Loess Plateau Grassland Ecosystem Research Station,Youyu,Shanxi 037200,China;Office of Research Administration,Shanxi Agricultural University,Taigu,Shanxi 030801,China)

机构地区：[1]山西农业大学草业学院,山西太谷030801 [2]草地生态保护与乡土草种质创新山西省重点实验室,山西太谷030801 [3]山西右玉黄土高原草地生态系统国家定位观测研究站,山西右玉037200 [4]山西农业大学科研管理部,山西太谷030801

出　　处：《草地学报》2022年第12期3199-3206,共8页Acta Agrestia Sinica

基　　金：山西农业大学高层次引进人才项目资助(2021XG008);国家重点研发计划(2017YFA0604802);山西省重点实验室项目(202104010910017)资助。

摘　　要：氮(N)、磷(P)是维持陆地生态系统生产力的重要营养元素,为探求磷添加和氮、磷的交互作用如何影响农牧交错带草地生态系统N_(2)O通量及调控机制,本研究设置对照(CK)、氮添加(N:缓释尿素10 g·m^(-2)·a^(-1))、磷添加(P:磷酸二氢钙10 g·m^(-2)·a^(-1))以及氮、磷同时添加(NP)4个处理,通过静态暗箱-气相色谱法测定2018和2019年生长季N_(2)O通量,通过结构方程模型等寻求氮、磷及其互作效应对N_(2)O通量的影响。结果表明:氮添加显著降低了2018年生长季N_(2)O排放,而磷添加显著降低了两年生长季N_(2)O排放;氮、磷同时添加削弱了单独氮或磷添加对N_(2)O排放的抑制作用;硝态氮、铵态氮和土壤含水量是N_(2)O通量的主要影响因素。因此,氮、磷添加对农牧交错带草地N_(2)O通量的影响存在显著的交互作用,并且受年际间温度和降水的调控,农牧交错带草地养分管理对N_(2)O通量的影响应考虑降水格局的变化。Nitrogen(N) and phosphorus(P) are two important nutrients for maintaining the productivity of terrestrial ecosystems.To investigate how P addition and the interaction of N and P affect N_(2)O flux and regulatory mechanisms of grassland ecosystems in agro-pastoral ecotone,four treatments(CK:control,N:nitrogen addition(N:urea 10 g·m^(-2)·a^(-1)),P:phosphorus addition(calcium dihydrogen phosphate 10 g·m^(-2)·a^(-1)),NP:(simultaneous addition of nitrogen and phosphorus) were set up in this study.The N_(2)O flux were measured by static dark box-gas chromatography in the growing seasons of 2018 and 2019,and the effects of N,P,and their interaction on N_(2)O fluxes were investigated by structural equation model(SEM).The results showed that N addition significantly reduced the N_(2)O emission in the 2018 growing season,while P addition significantly reduced the N_(2)O emission in both 2018 and 2019 growing seasons,and the simultaneous addition of N and P weakened the inhibitory effect of single nitrogen or phosphorus addition on N_(2)O emission;NO^(-)_(3)-N,NH^(+)_(4)-N and soil moisture content were the main factors that affected N_(2)O flux.In total,there was a significant interaction between N and P addition on N_(2)O flux of grassland in the agro-pastoral ecotone,and it was regulated by interannual temperature and precipitation.The change of precipitation patterns should be considered in the study of the effect of nutrient management on N_(2)O flux in the agro-pastoral ecotone.

关 键 词：养分添加 农牧交错带 N_(2)O排放 温室气体 

分 类 号：S812[农业科学—草业科学]