黄土高原紫花苜蓿土壤氮素丰缺指标和推荐施氮量初步研究  

Preliminary study of a sufficiency index of soil N and recommended N fertilizer application rates for alfalfa in the Loess Plateau of China

作　　者：孙洪仁[1] 王显国[1] 卜耀军[2] 乔楠[2] 任波 SUN Hong-ren;WANG Xian-guo;BU Yao-jun;QIAO Nan;REN Bo(College of Grassland Science and Technology,China Agricultural University,Beijing 100193,China;College of Life Sciences,Yulin University,Yulin 719000,China;Grassland Workstation of Yuyang District,Yulin 719000,China)

机构地区：[1]中国农业大学草业科学与技术学院,北京100193 [2]榆林学院生命科学学院,陕西榆林719000 [3]陕西省榆林市榆阳区草原工作站,陕西榆林719000

出　　处：《草业学报》2022年第4期32-42,共11页Acta Prataculturae Sinica

基　　金：国家现代农业产业技术体系建设项目(CARS-35)资助。

摘　　要：为了给黄土高原紫花苜蓿测土施肥奠定科学基础,搜集黄土高原紫花苜蓿施肥试验文献,提取土壤氮素含量、施氮处理和缺氮处理的产草量数据,采用零散试验数据整合法和养分平衡-地力差减法新应用公式,开展了该自然区域紫花苜蓿土壤氮素丰缺指标和推荐施氮量研究。结果表明,黄土高原生长第1年紫花苜蓿土壤碱解氮第1~6级丰缺指标为≥73、55~73、39~55、26~39、13~26和<13 mg·kg^(-1),土壤全氮第1~5级丰缺指标为≥1.5、1.1~1.5、0.7~1.1、0.4~0.7和<0.4 g·kg^(-1),土壤有机质第1~6级丰缺指标为≥19、13~19、9~13、5~9、2~5和<2 g·kg^(-1);生长第2年及以上紫花苜蓿土壤碱解氮第1~5级丰缺指标为≥79、51~79、30~51、13~30和<13 mg·kg^(-1);未区分生长年限紫花苜蓿土壤全氮第1~4级丰缺指标为≥1.9、1.2~1.9、0.5~1.2和<0.5 g·kg^(-1),土壤有机质第1~5级丰缺指标为≥24、13~24、6~13、2~6和<2 g·kg^(-1)。当目标产量为9.0~22.5 t·hm^(-2)、氮肥利用率为40%时,第1~6级土壤的推荐施氮量分别为0~0、68~169、135~338、203~506、270~675和338~844 kg·hm^(-2)。本研究初步建立了黄土高原紫花苜蓿土壤氮素丰缺指标推荐施肥系统,为该区域紫花苜蓿测土施氮提供了科学依据。The aim of this research was to lay a scientific basis for alfalfa(Medicago sativa)soil testing and fertilizer recommendation in the Loess Plateau region of China.The research methodology included a literature survey of alfalfa fertilization experiments conducted on the Loess Plateau,extracting data on soil nitrogen content and forage yield of N fertilizer treatments and where no N fertilizer was added.An algorithm for scattered experimental data integration and a new formula based on nutrient balance were employed to develop a sufficiency index(SI)of soil N with a scale of 1 to 6 and the recommended N fertilizer application rates(RNFAR)for alfalfa in the study region.It was found that for the planting year of an alfalfa crop(Y1)on the Loess plateau,the values for soil alkali-hydrolyzable nitrogen for SI levels 1 to 6 were,respectively,≥73,55-73,39-55,26-39,13-26 and<13mg·kg^(-1).Values for soil total nitrogen for SI levels 1 to 5 for Y1 were,respectively,≥1.5,1.1-1.5,0.7-1.1,0.4-0.7 and<0.4 g·kg^(-1).Values for soil organic matter for SI levels 1 to 6 for Y1 were,respectively,≥19,13-19,9-13,5-9,2-5 and<2 g·kg^(-1).For second and subsequent seasons,values for soil alkali-hydrolyzable nitrogen for levels 1 to 5 were,respectively,≥79,51-79,30-51,13-30 and<13 mg·kg^(-1).For the whole crop life(WCL)of alfalfa,values for soil total nitrogen for SI levels 1 to 4 were,respectively,≥1.9,1.2-1.9,0.5-1.2 and<0.5 g·kg^(-1).Values of soil organic matter for SI levels 1 to 5 for the WCL were,respectively≥24,13-24,6-13,2-6 and<2 g·kg^(-1).For a target yield of 9.0 t DM·ha^(-1) and an N fertilizer use efficiency of 40%,the RNFAR for SI levels 1 to 6 were,respectively,0,68,135,203,270 and 338 kg N·ha^(-1),while for a target yield of 22.5 t DM·ha^(-1) and an N fertilizer use efficiency of 40%,the corresponding values were,respectively,0,169,338,506,675 and 844 kg N·ha^(-1).This research has provisionally developed a system for calculating recommended fertilization rates for alfalfa crops on the Loess Plateau

关 键 词：紫花苜蓿 测土施肥 有机质 全氮 碱解氮 丰缺指标 施肥指标 施肥量 

分 类 号：S541.9[农业科学—作物学] S153.6