Estimation of economic and environmental potentials of variable rate versus uniform N fertilizer application to spring barley on morainic soils in SE Norway |
| |
| Authors: | Audun Korsaeth Hugh Riley |
| |
| Institution: | (1) Arable Crops Division, Norwegian Institute for Agricultural and Environmental Research, N-2849 Kapp, Norway |
| |
| Abstract: | Spring barley was grown for 4 years (2001–2004) in field trials at two sites on morainic soil in central SE Norway, with five N level treatments: 0, 60, 90, 120 and 150 kg N ha-1. Regression analyses showed that a selection of soil properties could explain 95–98% of the spatial yield variation and 47–90% of the yield responses (averaged over years). A strategy with uniform fertilizer application of 120 kg N ha−1 (U
N120) was compared with two variable-rate (VR) strategies, with a maximum N rate of either 150 kg N ha−1 (VRN150) or 180 kg N ha−1 (VRN180). These strategies were tested using either Norwegian prices (low price ratio of N fertilizer to yield value; PN/PY), or Swedish prices (high PN/PY). The VRN180 strategy had the highest potential yield and net revenue (yield value minus N cost) at both sites and under both price regimes. Using this strategy with Norwegian prices would increase the profit of barley cropping as long as at least 40 and 31% of the estimated potential increase in net revenue was realized, respectively. Using Swedish prices, uniform application appeared to be as good as or even better economically than the VR methods, when correcting for extra costs of VR application. The environmental effect of VR compared with uniform application, expressed as N not accounted for, showed contrasting effects when using Norwegian prices, but was clearly favourable using Swedish prices, with up to 20% reduction in the amount of N not accounted for. |
| |
| Keywords: | Environmental impact Fertilizer strategy Net revenue Price ratio effect Spatial variation Variable N rate Yield Yield response |
| 本文献已被 SpringerLink 等数据库收录！ |
|
