%0 Journal Article
%T Utilization rate of fertilizer N and dynamic changes of soil NO3--N in summer maize field in semi-humid area of Northwest China<br>半湿润地区农田夏玉米氮肥利用率及土壤硝态氮动态变化
%A FAN Ya-ning
%A LI Shi-qing
%A LI Sheng-xiu
%A <br>范亚宁
%J 应用生态学报
%D 2008
%I 
%X A field experiment on manual loessial soil was conducted to study the dynamic changes of NO3(-)-N in soil profile, utilization rate of fertilizer N, and relationships between N application rate and soil residual N accumulation during the growth period of summer maize under different N application rates (0, 45, 90, 135, and 180 kg hm(-2)). The results showed that in the whole growth period of summer maize, the NO3(-)-N concentration in the soil profile was the highest in 0-20 cm layer, and increased with increasing N application rate. The NO3(-)-N concentration in 0-60 cm soil layer changed significantly, but no significant change was observed in 60-100 cm soil layer. In the growth season of summer maize, soil NO3(-)-N accumulation presented a fluctuated decreasing trend due to the N uptake by crop and the precipitation. The N utilization rate (NUR) increased with increasing N application rate when the application rate was less than 135 kg hm(-2), but tended to decrease when the application rate exceeded 135 kg hm(-2). With the increase of N application rate, the N agronomy efficiency (NAE) decreased but the N physiology efficiency (NPE) increased. There was a significant positive correlation between soil residual N accumulation and N application rate (R2 = 0.957**, n = 5). The grain yield under N application was significantly higher than that without N application (P <0.05), and there existed a significant positive correlation between grain yield and N application rate (R2 = 0.934**, n = 5). In our experiment, the optimal application rate of fertilizer N was 135 kg hm(-2), which could harmonize the relationship between economic benefits and environment.
%K 施氮
%K 夏玉米
%K 氮肥利用率
%K 硝态氮
%K 半湿润地区
%K 农田
%K 夏玉米
%K 氮肥利用率
%K 土壤
%K 硝态
%K 氮动态变化
%K Northwest
%K China
%K area
%K field
%K summer
%K maize
%K soil
%K dynamic
%K changes
%K fertilizer
%K rate
%K 双赢
%K 环境
%K 效益
%K 施氮水平
%K 适宜施氮量
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=42FEDDFE54F8BCD9D5FD1926ABDD7722&aid=B0AB88550133FA4BFD0748ACA8A17F91&yid=67289AFF6305E306&vid=2A8D03AD8076A2E3&iid=E158A972A605785F&sid=5EEA08EFB4616D1C&eid=EDAEFEDAC1DCCBA4&journal_id=1001-9332&journal_name=应用生态学报&referenced_num=1&reference_num=29