Application of Controlled Release Urea Increased Maize N Uptake, Environmental Benefits and Economic Returns Via Optimizing the Temporal and Spatial Distribution of Soil Mineral N
The controlled-release urea (CRU) can provide an effective technical approach to improve the nitrogen use efficiency (NUE) and reduce environmental risks by formulating them to synchronize nitrogen (N) release according to the N demand of crops over the entire growing period. The evaluation of the effects of CRU on the maize yield and its application mechanism is of great importance to the development and utilization of CRU in the future. Field experiments were conducted for three maize growing seasons (2018-2020) in two places in Northeast China to investigate the effects of CRU on the yield, N uptake of maize and mineral N (Nmin) dynamics. The N balance of soil-crop system, ammonia (NH 3 ) volatilization, and economic benefit were also evaluated to illustrate the environmental and economic efficiency with CRU application. Four treatments were established including (1) no N fertilizer input (CK), (2) application of conventional urea at the optimum N application rate of 210 kg N ha -1 (U), (3) application of CRU (polyurethane-coated urea with an about 3-month N release period) at the equivalent N rate of U (PCU); and (4) application of CRU with 20% N reduction rate of PCU at 168 kg N ha -1 (0.8PCU). Our results indicated that the yield and NUE of maize in PCU treatment were increased by 4.3% (not significant) and 17.6% ( P< 0.05) compared with those in U. Even under 0.8PCU treatment with 20% reduction of N application rate, the maize yield was still sustained and NUE was increased by 20.6% ( P< 0.05). As for soil-crop N balance in agro-ecosystem, apparent N recovery rate was increased by 18.1% and apparent N losses rate was decreased by 36.2% in PCU compared to those in U in 2018 ( P< 0.05). Furthermore, it was observed that higher Nmin contents in 0-60 cm especially in 0-20 cm soil layer was improved under PCU compared to U at different growing stages, and the soil NO 3 - -N concentrations reached 9.8 mg kg -1 in PCU, but only 1.1 mg kg -1 in U in 0-20 cm soil layer at the maturity stage of maize. At the same time, the application of CRU decreased cumulative NH 3 volatilization loss during 17 days after base fertilization by 26.2%, and achieved 8.8% higher net profit compared with the application of conventional urea. It could be concluded that applying CRU could promote N uptake by maize, achieve better environmental and economic benefit through optimizing the temporal and spatial distribution of soil Nmin. And reasonable utilization of CRU (0.8PCU) can get better yield response to N nutrient supply. We suggested that CRU should be encouraged to further promote and popularize in maize production in the sustainable agriculture
Year of publication: |
[2022]
|
---|---|
Authors: | Sun, Mingxue ; Li, Juan ; Zhang, Lili ; Su, Xiaomeng ; Liu, Ning ; Han, Xiaori ; Wu, Songjiang ; Sun, Zhentao ; Yang, Xiangdong |
Publisher: |
[S.l.] : SSRN |
Saved in:
freely available
Saved in favorites
Similar items by person
-
Sun, Mingxue, (2021)
-
Su, Xiaomeng, (2021)
-
Xiwei, Zhong, (2007)
- More ...