摘要
通过研究苹果园生态条件下减施化学氮肥与有机无机配施N2O排放规律,为准确估算渭北旱塬区域N2O排放提供数据支撑。采用静态箱-气相色谱法对渭北旱塬苹果园不同施肥制度下(2017年10月-2018年10月)N2O排放通量进行田间监测。结果表明:苹果膨大期是渭北旱塬苹果园N2O排放的主要时期;各施肥处理N2O年累积排放总量在1.14~4.46 kg·hm^-2之间,与常规施肥处理相比,优化减氮和有机无机配施处理N2O排放总量分别降低了43.3%、42.6%;常规高氮、优化减氮与有机无机配施处理年排放系数分别为0.27%、0.22%、0.22%;温度是限制苹果成熟期和膨大期土壤N2O排放的决定因子;施肥后,随着时间的推移,底物浓度不足将逐渐成为限制N2O排放的重要因子。因此,有机无机配施作为苹果园推荐施肥模式的同时能够显著降低N2O排放,并且降雨前施肥可以降低N2O排放峰值。
Studying N2O emission characteristics of reducing chemical nitrogen(N)fertilizer and organic substitution in apple orchards under ecological conditions can provide data support for estimating regional N2O emissions in Weibei dry land.In this experiment,static box-gas chromatography was used to monitor N2O emission flux under different fertilization systems in apple orchards in Weibei dryland for a period of one year(Oct.2017-Oct.2018).The results showed that the apple expansion period was the main period of N2O emission from apple orchards on Weibei dry plateau.The total annual cumulative N2O emission of each fertilization treatment was between 1.14 kg·hm^-2 and 4.46 kg·hm^-2.Compared with conventional fertilization treatment,the total N2O emission of optimized N reduction and organic-inorganic combined fertilization treatments decreased by 43.3%and 42.6%,respectively.The annual emission coefficients of conventional high nitrogen,optimized N reduction,and organic-inorganic combined treatments were 0.27%,0.22%,and 0.22%,respectively.Temperature was the decisive factor limiting N 2 O emission from soil during apple maturity and expansion.After fertilization,with the passage of time,insufficient substrate concentration gradually became an important factor to limit N2O emission.Therefore,as the recommended fertilization mode for apple orchards,organic and inorganic fertilizers can significantly reduce N2O emission,and fertilization before rainfall can reduce N2O emission peak value.
作者
朱志军
杨莉莉
冯涛
同延安
ZHU Zhijun;YANG Lili;FENG Tao;TONG Yan’an(College of Resources and Environment,Northwest Agriculture and Forestry University,Yangling,Shaanxi 712100)
出处
《干旱地区农业研究》
CSCD
北大核心
2020年第1期59-65,共7页
Agricultural Research in the Arid Areas
基金
国家重点研发计划项目(2017YFD0200106)。
关键词
N2O排放
减氮施肥
有机无机配施
苹果园
N 2O emission
nitrogen reduction and fertilization
organic fertilizer substitution
apple orchard
