不同形式氮添加对草甸草原土壤磷素含量和碳氮磷化学计量特征的影响  

Effects of adding different types of nitrogen on soil phosphorus content and stoichiometric carbon,nitrogen,and phosphorus characteristics in meadow grassland

作　　者：汪梦寒 闫雨欣 李富翠 董利利 张亚楠 韩烈保[1] WANG Menghan;YAN Yuxin;LI Fucui;DONG Lili;ZHANG Ya’nan;HAN Liebao(School of Grassland Science,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学草业与草原学院,北京100083

出　　处：《草业科学》2023年第7期1793-1801,共9页Pratacultural Science

基　　金：北京林业大学大学生创新训练项目(S202110022171);中央高校基本科研业务费专项资金(BLX201940)。

摘　　要：由无机氮和有机氮沉降共同构成的大气氮沉降已成为全球变化的重要现象之一,影响着草原土壤磷循环过程。以内蒙古额尔古纳草甸草原为研究对象,进行了5年不同形式氮添加试验,设置的无机氮和有机氮比例分别为10꞉0(N_(1))、7꞉3(N_(2))、5꞉5(N_(3))、3꞉7(N4)、0꞉10(N5)和对照处理0꞉0(CK)。通过测定土壤有效磷含量、全磷含量及酸性磷酸酶活性,结合生态化学计量学来探究不同形式氮添加对草甸草原不同土层磷素含量和碳氮磷化学计量特征的影响。结果表明,不同形式氮添加对土壤全磷含量和酸性磷酸酶活性无显著影响(P>0.05);0-10 cm表层土壤有效磷含量在N_(2)处理下显著高于对照和其他氮添加处理(P<0.05)。土壤碳氮比(C/N)、碳磷比(C/P)、氮磷比(N/P)均不受氮添加形式的影响;0-10 cm表层土壤C/N、C/P、N/P均值低于全国平均水平。因此,有必要在更长的时间尺度上继续跟进不同形式氮添加对草原土壤磷循环的影响。Deposition of atmospheric nitrogen(N),which includes inorganic and organic N sources,has become an important phenomenon causing global change and affecting the grassland soil phosphorus(P)cycle.To study effects of different types of N addition on the soil P cycle,a five-year N addition experiment was carried out in the meadow steppe in Inner Mongolia.The inorganic(IN)to organic(ON)nitrogen ratios examined were 10꞉0(N_(1)),7꞉3(N_(2)),5꞉5(N_(3)),3꞉7(N4),0꞉10(N5)and 0꞉0(CK).By combining determination of soil available P content,total P content,and acid phosphatase activity with ecological chemometrics,this study explored the effects of different types of N addition on P content and stoichiometric characteristics in different soil layers of a meadow grassland.The results indicate that addition of different N types exerted no significant effect on soil total P content or acid phosphatase activity.The available P content in 0-10 cm topsoil under N_(2) treatment was significantly higher than that of control soil and soil receiving other N addition treatments.Soil C/N,C/P,and N/P were not affected by the type of added N.The average topsoil C/N,C/P,and N/P values in 0-10 cm topsoil are lower than the national average level,necessitating follow-up research spanning a longer time scale.

关 键 词：有机无机氮添加 全磷 有效磷 酸性磷酸酶 氮碳磷比 

分 类 号：S812.2[农业科学—草业科学]