Response of irrigated wheat to residual and fertilizer nitrogen

1981 ◽  
Vol 60 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Abdel-Hakeem M. Gomah ◽  
Fathi Amer
Keyword(s):  
Fertilizer Nitrogen ◽  
Irrigated Wheat

scholarly journals Supplementing Fertilizer Nitrogen Application to Irrigated Wheat at Maximum Tillering Stage Using Chlorophyll Meter and Optical Sensor

2013 ◽  
Vol 2 (1) ◽  
pp. 81-89 ◽  
Author(s):  
Bijay-Singh ◽  
Varinderpal-Singh ◽  
Yadvinder-Singh ◽  
H. S. Thind ◽  
Ajay-Kumar ◽  
...  
Keyword(s):  
Optical Sensor ◽  
Nitrogen Application ◽  
Fertilizer Nitrogen ◽  
Chlorophyll Meter ◽  
Irrigated Wheat

Site-Specific Fertilizer Nitrogen Management Using Optical Sensor in Irrigated Wheat in the Northwestern India

2017 ◽  
Vol 6 (2) ◽  
pp. 159-168 ◽  
Author(s):  
Bijay-Singh ◽  
Varinderpal-Singh ◽  
Yadvinder-Singh ◽  
H. S. Thind ◽  
Ajay Kumar ◽  
...  
Keyword(s):  
Optical Sensor ◽  
Nitrogen Management ◽  
Site Specific ◽  
Fertilizer Nitrogen ◽  
Northwestern India ◽  
Irrigated Wheat ◽  
Fertilizer Nitrogen Management

scholarly journals Responses of N<sub>2</sub>O and CH<sub>4</sub> fluxes to fertilizer nitrogen addition rates in an irrigated wheat-maize cropping system in northern China

2012 ◽  
Vol 9 (2) ◽  
pp. 839-850 ◽  
Author(s):  
C. Liu ◽  
K. Wang ◽  
X. Zheng
Keyword(s):  
Crop Yield ◽  
Crop Yields ◽  
Northern China ◽  
Field Studies ◽  
N2o Emissions ◽  
Fertilizer Rate ◽  
Fertilizer Nitrogen ◽  
Nitrogen Inputs ◽  
Irrigated Wheat ◽  
Fertilizer Rates

Abstract. Model and field studies generally posit that when the application rates of nitrogen fertilizer exceed crop needs, nitrous oxide (N2O) emissions will increase nonlinearly, though linear responses are also extensively reported by field studies. We conducted year-round measurements of crop yield, N2O and methane (CH4) fluxes for treatments of six fertilizer nitrogen levels (0, 135, 270, 430, 650 and 850 kg N ha−1 yr−1 in the form of urea) in a typical irrigated wheat-maize rotation field in northern China. Linear models characterized the responses of cumulative N2O emissions to fertilizer rates well; therefore, the calculated N2O emission factors of 0.17 ± 0.02%, 0.73 ± 0.05% and 0.49 ± 0.02% for the wheat season, maize season and annual scale, respectively, were appropriate for the different fertilizer rates. The cumulative CH4 uptake by the soil tended to be enhanced at higher fertilizer rates (≥350 kg N ha−1) in the maize season whereas no effect was observed for the wheat season. When the annual fertilizer rates increased from 270 to 430, from 270 to 650, and from 270 to 850 kg N ha−1 yr−1, the crop yields increased only 3 ∼ 15% (0.5 ∼ 2.1 t ha−1 yr−1), but cumulative N2O emissions increased 35 ∼ 115% (0.9 ∼ 3.0 kg N ha−1 yr−1). We recommend 270 kg N ha−1 yr−1 as the locally optimum fertilizer rate. Considering the nitrogen inputs by fertilization (270 kg N ha−1 yr−1), irrigation (4.3 ± 0.2 kg N ha−1 yr−1) and deposition (wet deposition: 30.5 ± 1.5 kg N ha−1 yr−1), the slightly positive soil nitrogen balance could maintain the current crop yield (∼13.8 t ha−1 yr−1) and reduce the present high N2O emissions (>3.51 kg N ha−1 yr−1) of the local farmers' practice (fertilizer rate > 430 kg N ha−1 yr−1).

Sign in / Sign up

Export Citation Format

Share Document