冬小麦冠层-大气氨交换的季节性特征及其影响因素  

Seasonal characteristics of canopy-atmosphere ammonia exchange and its influencing factors in a winter wheat field

作　　者：王吕[1] 景建元 李惠通 郑天义 李嘉[1] 吕慎强 周春菊[3] 王林权[1] WANG Lv;JING Jianyuan;LI Huitong;ZHENG Tianyi;LI Jia;LV Shenqiang;ZHOU Chunju;WANG Linquan(College of Resources and Environment,Northwest A&F University,Yangling,Shaanxi 712100,China;Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081,China;College of Life Sciences,Northwest A&F University,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]中国农业科学院农业资源与农业区划研究所,北京100081 [3]西北农林科技大学生命科学学院,陕西杨凌712100

出　　处：《干旱地区农业研究》2019年第6期256-264,273,共10页Agricultural Research in the Arid Areas

基　　金：国家重点研发计划项目(2017YFD0200105);陕西省重点研发计划(2018ZDCXL-SF-02-05)

摘　　要：为探究冠层氨交换对麦田氨挥发的贡献,从农学和生理角度揭示冠层氨挥发的机理,本文以冬小麦‘小偃22’和‘郑麦366’为材料,研究了不同生育期冬小麦冠层NH 3交换动态;枯、黄叶和根茬对冠层NH 3挥发的影响;监测了不同生育期的叶片硝酸盐含量、硝酸还原酶活性、谷氨酰胺合成酶活性、质外体铵浓度及可溶性蛋白含量等氮代谢指标,考察了其与冠层氨交换的关系。结果表明:冬小麦孕穗~扬花之前冠层吸收氨,为氨汇,其对农田氨挥发的消减率可达23%~40%;孕穗~扬花之后以冠层释放氨,为氨源,其对农田氨挥发的贡献率达17%~27%。小偃22冠层氨的吸收与挥发分别较郑麦366高28%~47%和19%~68%。氮肥施用下的土壤和冠层氨交换比不施氮处理高2.82~3.19 kg·hm-2和0.972~1.463 kg·hm-2,高肥力土壤和冠层氨交换比低肥力土壤高15.18~15.55 kg·hm-2和0.947~1.438 kg·hm-2。枯、黄叶对冠层氨挥发的作用受品种、生育期及土壤肥力等的影响。在高肥力和施氮(N180)条件下,收获后的麦茬也是氨释放源。冠层氨挥发与土壤温度、质外体铵浓度和可溶性蛋白呈显著线性正相关,与谷氨酰胺合成酶活性和硝酸盐含量呈显著线性负相关。结论:冬小麦营养生长期冠层与大气的氨交换以吸收为主,进入灌浆期后,以释放为主,氨交换方向受到生育期及氮素代谢过程的影响,同时也受到小麦品种和土壤肥力的影响。This study aimed to further explore the contribution of canopy ammonia exchange to ammonia volatilization in wheat field,and to reveal the mechanism of canopy ammonia emission in agronomic and physiological perspectives.In this paper,winter wheat‘Xiaoyan 22’and‘Zhengmai 366’were used as test materials to exam the effects of NH 3 exchange on NH 3 volatilization in wheat field at growing seasons,the effects of dry and yellow leaves on NH 3 emission,and the relationships between NH 3 volatilization and nitrogen metabolism indicators including nitrate reductase,glutamine synthetase activity,apoplast NH+4 and soluble protein content etc in leaves.The results showed that the NH 3 was absorbed by the shoots before booting-flowering,which reduced ammonia volatilization in wheat field by 23%~40%while NH 3 emission was from the shoots after the booting-flowering,which contributed to total field ammonia volatilization 17%~27%.The absorption and emission of canopy ammonia in Xiaoyan 22 were 28%~47%and 19%~68%higher than those of Zhengmai 366.Soil and canopy ammonia exchange under nitrogen application were 2.82~3.19 and 0.972~1.463 kg·hm-2 higher than that under no-nitrogen treatment.Soil and canopy ammonia exchange of fertile soil were 15.18~15.55 and 0.947~1.438 kg·hm-2 higher than that of infertile soil.The effects of dry and yellow leaves on the canopy NH 3 emission were affected by variety,growth period,and soil fertility.Under fertile soil and nitrogen application(N180),wheat stubble was also sources of ammonia release after post-harvest.The canopy NH 3 emission had a significantly positive linear relationship with soil temperature,apoplast NH+4 concentration,and soluble protein,and a negative linear relationship with glutamine synthetase activity and nitrate content significantly.It is concluded that the canopy absorbed ammonia from the atmosphere in the vegetative growth period of winter wheat,then it emitted ammonia during the reproduce stage,especially at late filling stage and maturity.The direction of am

关 键 词：冠层氨交换 硝酸盐含量 谷氨酰胺合成酶 质外体NH+4 可溶性蛋白 

分 类 号：S181.3[农业科学—农业基础科学]