氮添加对东祁连山高寒草甸土壤养分及地上生产力的影响  

Effects of nitrogen addition on soil nutrients and above-ground productivity in alpine meadow of east Qilian Mountains

作　　者：张玉琪 吴玉鑫 周会成 姜哲浩[1] 张德罡[1] 陈建纲[1] ZHANG Yu-qi;WU Yu-xin;ZHOU Hui-cheng;JIANG Zhe-hao;ZHANG De-gang;CHEN Jian-gang(College of Pratacultural Science,Gansu Agricultural University,Key Laboratory for Grassland Ecosystem of Min-istry of Education,Pratacultural Engineering Laboratory of Gansu Province,Sino-U.S.Centers for Grazingland Ecosystem Sustainability,Lanzhou 730070,China)

机构地区：[1]甘肃农业大学草业学院,草业生态系统教育部重点实验室,甘肃省草业工程实验室,中‐美草地畜牧业可持续发展研究中心,甘肃兰州730070

出　　处：《草原与草坪》2022年第6期50-55,共6页Grassland and Turf

基　　金：甘肃省草原技术推广总站“草原生态状况评价技术规范研究”(034-036272);甘肃省草原技术推广总站“中国两大草原分类系统在甘肃草原普查中的耦合研究”(034-036237)。

摘　　要：为探讨氮添加对退化高寒草甸土壤养分和地上生产力的影响,以祁连山东段高寒草甸草原为研究对象,在样地内分别施入0,10,20,30,40 g/m^(2)的尿素,测定不同施氮水平下地上生产力和不同土层土壤养分含量。结果表明:随着施氮量增加,地上生产力呈现升高趋势,施氮量在40 g/m^(2)下达到最大值194 g/m^(2);但过高的施氮量不能显著增加地上生产力,在施氮量大于30 g/m^(2)之后,地上生产力增加不显著;随着施氮量增加,0~20 cm土层土壤全氮和有机质含量降低,在施氮量40 g/m^(2)时最低,相比未施氮分别降低了19.95%和14.04%;在0~20,20~40,40~60 cm土层,铵态氮含量呈现先升高后降低的趋势,在20 g/m^(2)尿素下达到最大值;4个土层中,硝态氮的含量均呈现升高的趋势,在30 g/m^(2)尿素水平下达到最大值;在各个土层中,速效磷含量整体呈现随土层深度增加先升高后降低的趋势,施氮量与土壤全磷,全钾和速效钾之间均没有显著相关性。In order to explore the effects of nitrogen application on soil nutrients and above-ground productivity of degraded alpine meadow,this study took the alpine meadow in the eastern section of Qilian Mountains as the research object,and applied 0,10,20,30,40 g/m^(2) urea to measure above-ground productivity and soil nutrient content in different soil layers under different nitrogen application levels. The results showed that the aboveground productivity increased with the increase of nitrogen application rate,but too low or too high nitrogen application rate did not significantly increase aboveground productivity. With the increase of nitrogen application rate,the contents of soil total nitrogen and organic matter decreased;however the contents of ammonium nitrogen,nitrate nitrogen and available phosphorus increased significantly. There was no significant correlation between N application rate and soil total P,total K and available K. In this area,the optimal amount of nitrogen application was 30 g/m^(2).

关 键 词：氮添加 高寒草甸 生产力 土壤养分 

分 类 号：S812[农业科学—草业科学]