Blending urea and slow-release nitrogen fertilizer increases dryland maize yield and nitrogen use efficiency while mitigating ammonia volatilization

Long−term excessive nitrogen fertilizer input has resulted in several environmental problems, including an increase in N2O emissions and the aggravation of nitrate leaching; monitoring nitrogen fertilizer is crucial for maize with high yield. This study aimed to optimize the amount of nitrogen applied to maize by Climate−Smart Agriculture (CSA) so as to continuously improve agricultural productivity and reduce or eliminate N2O emissions as much as possible. Field experiments with a completely randomized design were conducted to examine the effects of six nitrogen treatments (N application levels of 0, 120, 180, 240, 300, 360 kg·ha−1, respectively) on N2O emissions, residual concentration of nitrate and ammonium nitrogen, maize yield, and nitrogen utilization efficiency in 2018 and 2019. The results indicated that the residual concentration of nitrate nitrogen (NO3-−N) in the two seasons significantly increased; N2O emissions significantly increased, and the nitrogen fertilizer agronomic efficiency and partial productivity of maize fell dramatically as the nitrogen application rate increased. The maize grain yield rose when the N application amount was raised (N application amount <300 kg·ha−1) but decreased when the N application amount > 300 kg·ha−1. An increase in the nitrogen application rate can decrease nitrogen use efficiency, increase soil NO3-−N residual, and N2O emissions. Reasonable nitrogen application can increase maize yield and reduce N2O emissions and be conducive to improving nitrogen use efficiency. By considering summer maize yield, nitrogen use efficiency, and farmland ecological environment, 173.94~178.34 kg N kg·ha−1 could be utilized as the nitrogen threshold for summer maize in the North China Plain.

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Application of biochar-coated urea controlled loss of fertilizer nitrogen and increased nitrogen use efficiency

Chemical and Biological Technologies in Agriculture ◽

10.1186/s40538-020-00205-4 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Yiman Jia ◽

Zhengyi Hu ◽

Yuxin Ba ◽

Wenfang Qi

Keyword(s):

Oilseed Rape ◽

Nitrogen Uptake ◽

Nitrogen Use Efficiency ◽

Nitrogen Fertilizer ◽

Ammonia Volatilization ◽

Nitrogen Loss ◽

Nitrogen Use ◽

Coated Urea ◽

Use Efficiency ◽

The Impact

Abstract Background The use of biochar-based N fertilizers have been considered among the most effective strategy for reducing nitrogen loss and improving nitrogen use efficiency (NUE). However, effect and mechanism of biochar-coated urea (BCU) controlling the loss of nitrogen from soil and NUE are rarely reported. Methodology In this study, a 65-d culture pot experiment of oilseed rape was used to investigate the impact of BCU on nitrogen leaching, ammonia volatilization, soil nitrogen concentrations, soil pH, nitrogen uptake, NUE and oilseed rape biomass as compared with urea and urea combined with biochar at same nitrogen level. Results Results showed that the application of BCU could minimize nitrogen loss mainly by reducing nitrate leaching loss; which could be attributed to the slow-release performance of BCU, followed by biochar induced adsorption/fixation of nitrogen due to the porous nature and surface functional groups of biochar. However, the application of BCU enhanced ammonia volatilization due to the increase of soil NH4+–N concentration and pH value of microenvironment around urea by BCU. The application of BCU increased NUE by about 20% when compared with urea, since BCU reduced losses of nitrogen fertilizer and increased concentration of nitrogen in the soil as well as nitrogen uptake in oilseed rape. Furthermore, the reduction of nitrogen application by 20% when BCU served as a nitrogen source not only reduced nitrogen loss but significantly improved NUE, with no negative effect on the biomass of oilseed rape. Conclusion BCU can serve as a promising control release nitrogen fertilizer for reducing loss of nitrogen and increasing NUE. However further investigations are required to validate the dosage-effect relationship of BCU on crop yield at the field scale.

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Growth, grain yield, water and nitrogen use efficiency of rainfed maize in response to straw mulching and urea blended with slow-release nitrogen fertilizer: A two-year field study

Archives of Agronomy and Soil Science ◽

10.1080/03650340.2021.1912323 ◽

2021 ◽

Author(s):

Jinjin Guo ◽

Junliang Fan ◽

Fucang Zhang ◽

Shicheng Yan ◽

You Wu ◽

...

Keyword(s):

Grain Yield ◽

Field Study ◽

Nitrogen Use Efficiency ◽

Nitrogen Fertilizer ◽

Slow Release ◽

Nitrogen Use ◽

Straw Mulching ◽

Use Efficiency

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Impacts of Slow-Release Nitrogen Fertilizer Rates on the Morpho-Physiological Traits, Yield, and Nitrogen Use Efficiency of Rice under Different Water Regimes

Agriculture ◽

10.3390/agriculture12010086 ◽

2022 ◽

Vol 12 (1) ◽

pp. 86

Author(s):

Alaa AL Aasmi ◽

Jiuhao Li ◽

Yousef Alhaj Hamoud ◽

Yubin Lan ◽

Kelvin Edom Alordzinu ◽

...

Keyword(s):

Nitrogen Use Efficiency ◽

Nitrogen Fertilizer ◽

Slow Release ◽

Rice Production ◽

Growth And Yield ◽

Specific Information ◽

Nitrogen Use ◽

Water Regimes ◽

Use Efficiency ◽

Fertilizer Rates

The efficient use of water and fertilizer is vital for optimizing plant growth and yield in rice production. To achieve sustainable rice production and resource management, the ways in which applied water and nitrogen affect the root and shoot morpho-physiology, as well as yield, must be understood. In this study, a pot experiment was conducted to investigate the effects of slow-release nitrogen fertilizer (sulfur-coated urea) application at three levels (light nitrogen (NL), medium nitrogen (NM), and heavy nitrogen (NH)) on the growth, yield, and nitrogen use efficiency (NUE) of rice grown under three water regimes (wetting and soil saturation (WSS), wetting and moderate drying (WMD) and wetting and severe drying (WSD)). The results revealed that differences in water regimes and fertilizer rates led to significant differences in the roots, shoots, yield, and NUE of rice. Increasing the N dosage by 5% enhanced the root and biomass production by 16% in comparison with that of the other groups. The NH×WSS treatment produced the greatest root length, weight, density, active absorption, and oxidation. However, the integration of WSS × NL generated the maximum value of nitrogen apparent recovery efficiency (63.1% to 67.6%) and the greatest value of nitrogen partial factor productivity (39.9 g g−1 to 41.13 g g−1). Transmission electron microscopy (TEM) images showed that plants grown under high and medium nitrogen fertilizer rates with WSS had improved leaf mesophyll structure with normal starch grains, clear cell walls, and well-developed chloroplasts with tidy and well-arranged thylakoids. These results show that TEM images are useful for characterizing the nitrogen and water status of leaves in the sub-micrometer range and providing specific information regarding the leaf microstructure. The findings of this study suggest that the application of NH×WSS can produce improvements in growth traits and increase rice yield; however, the NL×WSS treatment led to greater NUE, and the authors recommend its usage in rice agriculture.

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