氮沉降对贝加尔针茅草原土壤酶活性的影响  

Effects of Nitrogen Deposition on Soil Enzyme Activities of Stipa baicalensis Steppe

作　　者：刘红梅[1] 周广帆 李洁[1] 王丽丽[1] 王慧[1] 杨殿林[1] LIU Hongmei;ZHOU Guangfan;LI Jie;WANG Lili;WANG Hui;YANG Dianlin(Agro-Environmental Protection Institute,Ministry of Agriculture,Tianjin 300191,China)

机构地区：[1]农业部环境保护科研监测所,天津300191

出　　处：《生态环境学报》2018年第8期1387-1394,共8页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(31170435)

摘　　要：草原土壤酶作为土壤中最活跃的组分,影响生态系统的物质循环过程,其活性能快速反映氮沉降对土壤环境的变化。以内蒙古贝加尔针茅草原为研究对象,于2010年开始实施模拟氮沉降试验,设置对照(N0,0 kg·hm^(-2)·a^(-1))、低氮(N30,30 kg·hm^(-2)·a^(-1);N50,50 kg·hm^(-2)·a^(-1))、高氮(N100,100 kg·hm^(-2)·a^(-1);N150,150 kg·hm^(-2)·a^(-1);N200,200 kg·hm^(-2)·a^(-1))6种氮处理,研究不同氮沉降水平对贝加尔针茅草原土壤6种酶(脲酶、酸性磷酸酶、过氧化氢酶、过氧化物酶、多酚氧化酶和蔗糖酶)活性影响。结果表明,0~10 cm土层,与对照相比,氮沉降处理均降低了土壤脲酶(1.32%~24.54%)、过氧化氢酶(10.34%~46.41%)、过氧化物酶(40.54%~271.43%)和蔗糖酶(2.88%~7.31%)活性。同一氮处理水平,不同深度土层的脲酶、酸性磷酸酶、多酚氧化酶和蔗糖酶活性表现为0~10 cm>10~20 cm。相关分析表明,土壤含水量、p H、有机碳、全氮、铵态氮、硝态氮、微生物生物量碳和微生物生物量氮含量与酶活性具有显著相关性(P<0.05)。以上结果表明,氮沉降通过改变草原土壤的环境因子,影响土壤酶活性。As one of the most active components of grassland soil,soil enzymes contribute to the processes of material circulation in the ecosystem which can quickly reflect the changes of soil environment caused by nitrogen deposition.An in-situ field experiment was established to examine the effects of increased nitrogen deposition on the activities of soil enzymes of Stipa baicalensis Steppe in Inner Mongolia.Nitrogen was added at six levels,a control(N0,0 kg·hm^-2·a^-1),low-N(N30,30 kg·hm^-2·a^-1;N50,50 kg·hm^-2·a^-1),high-N(N100,100 kg·hm^-2·a^-1;N150,150 kg·hm^-2·a^-1;N200,200 kg·hm^-2·a^-1)to simulate increasing nitrogen deposition starting in june 2010.Effects of different nitrogen addition on soil urease,acid phosphtase,catalase,peroxidase,polyphenol oxidase and invertase actiities in 0~10 cm and 10~20 cm soil layer were quantified.The results showed that,increased nitrogen deposition decreased soil urease(1.32%~24.54%),catalase(10.34%~46.41%),peroxidase(40.54%~271.43%)and invertase(2.88%~7.31%)activities compared with the control at 0~10 cm soil layer.For different soil layers under the same degrees of nitrogen depositon,soil urease,acid phosphtase,polyphenol oxidase and invertase activities in 0~10 cm soil layer was higher than those in 10~20 one.Significant correlations of soil enzyme activities with soil water content,pH,total organic C,total N,NH4^+-N,NO3^--N,microbial biomass carbon,and microbial biomass nitrogen were established(P<0.05).These results suggest that increased nitrogen deposition could affect the soil enzymatic activities by influencing environmental factors of grassland soil.

关 键 词：氮沉降 贝加尔针茅草原 土壤理化性质 土壤酶活性 

分 类 号：S154.1[农业科学—土壤学] X171[农业科学—农业基础科学]