|
|
|
| Effects of nitrogen application rates on soil water, temperature, carbon nitrogen, and maize yield in Yanghuang irrigation area |
| MIAN Youming, MIAO Fangfang, WU Pengnian, WANG Yuening, HOU Xianqing* |
| School of Agriculture, Ningxia University, Yinchuan, Ningxia 750021, China |
|
|
|
|
Abstract To solve some problems that low precipitation and low temperature in spring are not conducive to maize emergence and growth, and high temperature stress in the middle and late stage of crop growth leads to the low productivity of maize in Yanghuang irrigation area of Ningxia, a field experiment was conducted to investigate the effects of total straw returning(9 000 kg/hm2)combined with three different pure nitrogen application rates under the condition of drip irrigation on soil moisture, temperature, soil carbon and nitrogen(soil organic carbon, total nitrogen content and carbon-nitrogen ratio), maize yield and water productivity. The nitrogen fertilization was applied with three different rates: 150, 300 and 450 kg/hm2(i.e. treatment N1, N2, N3)in present study, while the no nitrogen fertilizer application was marked the control treatment(CK). The results show that N3 treatment has the best effect on increasing soil organic carbon and total nitrogen contents in 0-40 cm soil layer, which are significantly increased by 41.5% and 41.7% compared to CK treatment, respectively.While N2 treatment has the most significant effect on regulating soil C/N, which is significantly increased by 5.2% compared to CK treatment. The application of nitrogen fertilizer can improve the soil temperature at 0-25 cm layer during the seedling stage(20 days after sowing), and it has a good soil water conservation effect on the soil of 0-100 cm layer during the growth stage of maize. The soil temperature adjustment and water conservation under N2 treatment is the best. Treatment N1 and N2 can significantly affect the maize yield components, and significantly increase the yield by 46.2%-63.7% compared to CK treatment. Meanwhile, N2 treatment can significantly improve the maize water productivity by 36.1%, compared with CK treatment. It can be seen that straw returning combined with pure nitrogen 300 kg/hm2 has the best effect on regulating soil water and heat environment, soil carbon-nitrogen ratio, and promoting maize yield and water productivity in Yanghuang irrigation area of Ningxia.
|
|
Received: 15 November 2019
|
|
|
|
|
|
|
