旱地土壤铵态氮和硝态氮累积特征及其与小麦产量的关系  

Characteristics of ammonium N and nitrate N accumulation in dryland soil in relation with wheat yield

作　　者：苗艳芳[1] 李生秀[2] 扶艳艳[1] 王朝辉[2] 徐晓峰[1] 罗来超[1] 

机构地区：[1]河南科技大学农学院,河南洛阳471003 [2]西北农林科技大学资源环境学院,陕西杨凌712100

出　　处：《应用生态学报》2014年第4期1013-1021,共9页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(30971866);洛阳市科技攻关项目(1203206B)资助

摘　　要：在陕西永寿和河南洛阳分别进行了11处和7处小麦大田试验，设对照（不施氮）和施氮（150kgN·hm-2）2个处理，测定了小麦生物量、籽粒产量及不同土层（0—20、20—40、40～60、60—80、80～100cm）土壤铵态氮、硝态氮浓度．结果表明：两地土壤铵态氮浓度均很低，而硝态氮浓度较高，其中硝态氮数量占铵态氮、硝态氮总量的91％，在反映土壤供氮特性方面与两者之和有完全一致趋势．不施氮情况下，永寿0～40、0—60、0～80和0～100cm土层累积的硝态氮与小麦生物量和产量显著相关；而洛阳无显著相关关系．施氮后，永寿不同深度土层累积的硝态氮与小麦生物量和产量的相关关系显著下降，而洛阳出现负相关；两地小麦产量增量与0—80和0—100cm土层累积的硝态氮显著或极显著相关．小麦苗期主要依赖0～20em土层硝态氮；返青期、拔节期分别利用0—40cm和0—60cm土层硝态氮，成熟期则能利用0—100cm土层累积硝态氮．小麦收获后对照土壤的铵态氮浓度与播前起始值无明显差异，而硝态氮大幅下降．A total of eleven field trials in Yongshou, Shaanxi Province and seven in Luoyang, Henan Province were conducted with two treatments （without N as control and with 150 kg N· hm-2 addition）. The wheat biomass and seed yield were determined, and so were the nitrate and ammonium N concentrations in five layers （0-20, 20-40, 40-60, 60-80, 80-100 cm） at each trial site. Results showed that soil ammonium concentrations in the two provinces were very low while nitrate N concentrations were relatively high. Soil nitrate N occupied 91% of the total mineral N, and exhibited the same trend as the total mineral N in reflecting soil N supplying capacity. Without N application, the cumulative nitrate N amounts in the 0-40, 0-60, 0-80 and 0-100 cm layers in Yongshou were significantly correlated with wheat biomass and seed yield while no such correlation existed in Luoyang. With N addition, the relations of cumulative nitrate N of the differ- ent layers to wheat biomass and yield were greatly declined in Yongshou whereas those of Luoyang were changed to be negative. The yield increases were significantly correlated with the amount of ni- trate N accumulated in the 0-80 and 0-100 cm layers of the two sites under N addition. Wheat mainly depended on nitrate N from the 0-20 em layer at seedling stage, 0-40 cm at reviving, and 0-60 cm at elongation stages, and could utilize 0-100 cm nitrate N at maturity. After wheat har- vest, the concentration of ammonium N was not significantly different from the initial value while that of nitrate N greatly decreased.

关 键 词：小麦 硝态氮 铵态氮 

分 类 号：S512.1[农业科学—作物学]