施肥对黄土高原紫花苜蓿草地N2O通量及生产性能的影响  

Effects of Nitrogen Addition on N_(2)O Fluxes and Productivity of Lucerne Grasslands on the Loess Plateau

作　　者：李渊 张清平 王涛 沈禹颖 LI Yuan;ZHANG Qing-ping;WANG Tao;SHEN Yu-ying(College of Pastoral Agriculture Science and Technology,State Key Laboratory of Grassland Agro-ecosystems,Lanzhou University,National field scientific obserlation and research station of grassland agro-ecosytems in Gansu Qingyang,Lanzhou,Gansu Province 730020,China)

机构地区：[1]兰州大学草地农业科技学院草地农业生态系统国家重点实验室甘肃庆阳草地农业生态系统国家野外科学观测研究站,甘肃兰州730020

出　　处：《草地学报》2022年第6期1584-1589,共6页Acta Agrestia Sinica

基　　金：国家自然科学基金(31872416,32101431);国家牧草产业技术体系(CARS-34)资助。

摘　　要：以黄土高原旱区5年龄的紫花苜蓿为(Medicago sativa)研究对象,设置4个施氮处理水平:0 kg·hm^(-2)(N0),50 kg N·hm^(-2)(N50),100 kg N·hm^(-2)(N100)和150 kg N·hm^(-2)(N150)。选取排放系数、N肥利用率和氧化亚氮(N_(2)O)通量作为N利用效率及N_(2)O排放的评价指标,选择叶面积指数、干物质(Dry matter,DM)产量、粗蛋白(Crude protein,CP)、中性洗涤纤维(Neutral detergent fiber,NDF)和酸性洗涤纤维(Acid detergent fiber,ADF)、相对饲用价值(Relative feed value,RFV)作为生产性能和营养品质指标,探究不同施N量对苜蓿草地N_(2)O通量及生产性能的影响,并通过灰色关联分析法对其进行评估,以期获得协调N_(2)O减排与提高生产性能的最佳施N量。结果表明:施N增加苜蓿草地每公顷DM产量,N150处理下头茬产量最高,达到8885 kg·hm^(-2);N肥施入能提高苜蓿CP含量,并提高饲用品质(降低ADF和NDF含量);灰色关联分析结果中N50排序最优,并与N150归为一类。因此,综合考虑N_(2)O通量和生产性能,该地区苜蓿草地最佳施N量为50 kg N·hm^(-2)。To understand the effects of nitrogen(N)application on nitrous oxide(N_(2)O)flux and production performance(leaf area index,dry matter(DM)yield,crude protein,acid detergent fiber,neutral detergent fiber,and relative feed value)of lucerne(Medicago sativa)grasslands,four levels of N addition:N0(0 kg N·hm^(-2)),N50(50 kg N·hm^(-2)),N100(100 kg N·hm^(-2))and N150(150 kg N·hm^(-2))were applied in 5-years lucerne grasslands at the Lanzhou University Loess Plateau Research Station.Results showed that N addition enhanced DM yield of lucerne,DM yield of first harvest reached the highest for 8885 kg·hm^(-2) with N150.N addition raised lucerne crude protein contents,and reduced acid detergent fiber and neutral detergent fiber content;grey correlation analysis showed that the N50 treatment was optimal since it comprehensively reduced N_(2)O flux and increased productivity of lucerne grasslands.

关 键 词：氮肥 温室气体 灰色关联评价 黄土高原 

分 类 号：S963.223.3[农业科学—水产养殖]