摘要
【目的】对于农田指定地头模拟滴灌施肥,研究不同灌水和施氮处理下硝态氮的分布规律。【方法】设置4种灌水方式:27(W1)、54(W2)、81(W3)、108(W4)mm;4种施氮方式:0(N0)、52.5(N1)、105(N2)、157.5(N3)kg/hm2。【结果】常规施氮(52.5 kg/hm2)时,灌水量达81和108 mm会引起硝态氮在70 cm土层大量积累,容易造成淋失;常规灌水(54 mm)时,施氮量低于或高于常规处理(52.5 kg/hm2)同样引起硝态氮在同一土层深度的显著降低。【结论】常规灌水条件下不同氮肥处理硝态氮平均含量在垂直方向随土层深度增加而减小,70 cm处硝态氮残留量为N1<N2<N3;水平方向0～30 cm硝态氮平均含量逐渐减小,在湿润峰处未发现硝态氮累积现象。常规施氮条件下,W1(27 mm)和W2(54 mm)处理硝态氮平均含量分别随土层深度的增加而减小,主要集中在0～30 cm土层;当灌水量达W3(81 mm)和W4(108 mm)时硝态氮含量沿土层竖直方向逐渐增大,70 cm处残留量大小为W3<W4,发生了严重的淋洗下渗;增大灌水量在水平方向湿润峰附近同样出现硝态氮累积现象。
[ Objective ] Simulation of drip fertigation on the specified field was carried out and the regularities of nitrate nitrogen distribution of different irrigation and nitrogen was discussed. [ Method ] Four irrigation were set as 27 （ W1 ）, 54 （ W2 ）, 81 （ W3 ） and 108 （ W4 ） mm ; four nitrogen application rates were set as 0 （ N0 ）, 52.5 （ N1 ）, 105 （ N2 ）, 157.5 （ N3 ） kg/hm^2, and among them zero rate meant that only water was irrigated without nitrogen. [ Results ] The results indicated that when the irrigation amount reached 81 mm and 108 mm, significant amount of residual soil nitrate was found in the 70 cm soil layers, which would result in the eluviation. The normal irrigation （54mm）, lower or higher than the conventional treatment （52.5 kg/ hm^2） would also lead to significant nitrate decrease in the same soil depth. [ Conclusion ] In the normal irrigation condition, different nitrogen treatments of nitrate nitrogen content in the vertical direction decreased with the increase of soil depth, residual nitrate at 70 cm was N1 〈 N2 〈 N3 ; the average content of nitrate nitrogen decreased slowly in 0 - 30 cm in horizontal direction in soil, and there was no accumulation phenomenon at the soil wetness peak. In the conventional nitrogen condition, nitrate nitrogen content in the vertical direction decreased with the increasing soll depth under the W1 （27 mm） and W2 （54 mm） treatment, mainly in the 0 - 30 cm soil layer. While nitrate nitrogen average content increased vertically in soil under the W3 （81 mm）and W4 （108 mm）treatment, and residual nitrate at 70cm was W3 〈 W4, nitrate nitrogen would leak down. The increase of irrigation volume would also lead to the phenomenon of accumulation of nitrate nitrogen near the soil wetness peak.
出处
《新疆农业科学》
CAS
CSCD
北大核心
2013年第5期875-881,共7页
Xinjiang Agricultural Sciences
基金
国家高技术研究发展计划("863"计划)"棉花规模化生产精准作业技术与装备"(2012AA101902)
国家科技支撑计划"棉花田间精准作业技术规模化与示范"(2012BAD41B02)
关键词
滴灌施肥
灌水施肥量
土层剖面
硝态氮累积
dripping fertigation
irrigation volume
soil profile
accumulation of nitrate nitrogen
