盐渍化草地根际土壤理化性质对降水改变和氮添加的响应  

Response of Rhizosphere Soil Properties to Changed Precipitation and Nitrogen Addition in a Salinized Grassland

作　　者：赵芳草 陈鸿飞 王一昊 董宽虎[1,2,3] 王常慧 陈晓鹏[1,2,3] ZHAO Fang-cao;CHEN Hong-fei;WANG Yi-hao;DONG Kuan-hu;WANG Chang-hui;CHEN Xiao-peng(College of Grassland Science,Shanxi Agricultural University,Taigu,Shanxi Province 030801,China;Shanxi Key Laboratory of Grassland Ecological Protection and Native Grass Germplasm Innovation,Taigu,Shanxi Province 030801,China;Youyu Loess Plateau Grassland Ecosystem National Research Station,Youyu,Shanxi Province 037200,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

出　　处：《草地学报》2022年第9期2430-2437,共8页Acta Agrestia Sinica

基　　金：国家自然科学基金(31800402);山西省高等学校科技创新项目(2020L0144);山西农业大学科技创新基金(2018YJ34)资助。

摘　　要：为揭示盐渍化草地根际效应及其对降水改变和氮添加的响应,对增水、减水和氮添加及其交互处理下晋北盐渍化草地根际和非根际土壤理化性质进行分析。研究发现:与对照相比,减水及减水+氮添加显著提高了土壤交换性Na^(+)含量,氮添加提高了非根际土壤208.1%的硝态氮和105.3%的无机氮含量(P<0.05);增减降水与氮添加交互对根际和非根际土壤理化性质均无显著影响;根际土壤pH值比非根际低0.25个单位,铵态氮、硝态氮、有机酸、氨基酸、全碳和全氮含量分别比非根际高412.0%,81.4%,37.5%,22.4%,37.3%和43.6%(P<0.05);主成分分析发现根际和非根际土壤理化性质对水、氮交互处理的响应具有明显差异。表明盐渍化草地植物具有较强的根际效应,但其对增加降水及水、氮交互的响应不敏感,结果可为预测未来降水变化和大气氮沉降增加情境下盐渍化草地根际效应和土壤理化性质变化提供理论依据。To reveal the soil rhizosphere effect and its response to changed precipitation and nitrogen(N)addition,we analyzed the rhizosphere and non-rhizosphere soil properties in a salinized grassland under six treatments including increasing precipitation by 50%,decreasing precipitation by 50%,N addition(10g N·m^(-2)·a^(-1)),increasing precipitation by 50%plus N addition,decreasing precipitation by 50%plus N addition.The results showed that decreasing precipitation by 50%and decreasing precipitation by 50%plus N addition significantly increased the concentration of exchangeable Na^(+) in rhizosphere and non-rhizosphere soil(compared to control),respectively.The N addition increased nitrate and inorganic N concentrations in non-rhizosphere soil by 208.1%and 105.3%,respectively.There has been no interaction found between changed precipitation and nitrogen addition on soil properties in rhizosphere and non-rhizosphere soil.The pH of rhizosphere soil was significantly lower than that of nonrhizosphere soil by 0.25units,and the concentrations of ammonium,nitrate,organic acids,amino acids,total carbon,and total N in rhizosphere soil were significantly higher than those of non-rhizosphere soil by 412.0%,81.4%,37.5%,22.4%,37.3%,and 43.6%,respectively.Through principal component analysis,it was found that there were significant differences in the response of rhizosphere and non-rhizosphere soil properties to changed precipitation and N addition.The results showed that plants in salinized grassland had a strong rhizosphere effect,but they were not sensitive to increased precipitation and interaction between changed precipitation and N addition.The results can provide a theoretical basis for predicting the rhizosphere effect and soil properties of salinized grassland under the scenario of future precipitation change and atmospheric nitrogen deposition increase.

关 键 词：根际效应 盐碱土壤 降水改变 氮输入 土壤养分 

分 类 号：S156.44[农业科学—土壤学]