Ammonia emission from staple crops in China as response to mitigation strategies and agronomic conditions: Meta-analytic study

Economic losses and environmental hazards are meaningful problems of emitted ammonia induced by extensive use of synthetic nitrogen fertilizers. The concept presented as yield scaled fertilizer productivity (YSFP) in our meta-analysis in addition to nitrogen use efficiency (NUE), nitrogen agronomic efficiency (NAE), and productivity of applied nitrogen (PAN) were used to weight ammonia emission (AV)-induced reductions in wheat, maize, and rice production. The comprehensive meta-analysis was used to weight the reductions in these parameters by AV as the difference between observed means of the collected studies and their adjusted means using AV factor. There were higher reductions in agronomic production induced by AV in rice than maize and wheat. AV-induced reductions in PAN of rice, maize, and wheat were decreased by 4.99, 3.71, and 2.42 (kg grains kg−1 N), respectively. YSFP and PAN recorded the highest sensitivity to AV in wheat (R2 = 0.88 for both) and rice (R2 = 0.92 and 0.89, respectively), while NUE was the most efficient parameter in weighting AV agronomic effects (R2 = 0.81). Slow-released N fertilizers resulted in the lowest reductions in AV agronomic parameters followed by organic amendments and then urea while using other synthetic fertilizers recorded the highest reductions by 3.90, 6.40, 1.41, and 4.70 in YSFP, NUE, NAE, and PAN, respectively. Inhibitors had the highest effect on mitigating AV agronomic losses compared with biochar and mulching and affected the parameters following that order as percentages of no amendments, YSFP (52.63%) > PAN (47.18%) > NUE (40.83%) > NAE (38.75%). This study outlines the reductions in agronomic production induced by AV and weights the efficiency of various mitigation strategies under various agronomic conditions. The results proved the efficiency of YSFP with NUE parameters to weight the effect of AV on crop yield, while suggesting to find out more applicable parameters in further studies.

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Improved gridded ammonia emission inventory in China

10.5194/acp-2021-439 ◽

2021 ◽

Author(s):

Baojie Li ◽

Lei Chen ◽

Weishou Shen ◽

Jianbing Jin ◽

Teng Wang ◽

...

Keyword(s):

Atmospheric Chemistry ◽

Emission Inventory ◽

Mainland China ◽

Fertilizer Application ◽

Mitigation Strategies ◽

Ammonia Emission ◽

Emission Inventories ◽

Livestock Waste ◽

Nh3 Emission ◽

Spatial Differences

Abstract. As a major alkaline gas in the atmosphere, NH3 significantly impacts atmospheric chemistry, ecological environment, and biodiversity. Gridded NH3 emission inventories can significantly affect the accuracy of model concentrations and play a crucial role in the refinement of mitigation strategies. However, several uncertainties are still associated with existing NH3 emission inventories in China. Therefore, in this study, we focused on improving fertilizer application-related NH3 emission inventories. We comprehensively evaluated the dates and times of fertilizer application to the major crops that are cultivated in China, improved the spatial allocation methods for NH3 emissions from croplands with different rice types, and established a gridded NH3 emission inventory for mainland China with a resolution of 5 min × 5 min in 2016. The results showed that the atmospheric NH3 emissions in mainland China amounted to 12.11 Tg, with livestock waste (44.8 %) and fertilizer application (38.6 %) being the two main NH3 emission sources in China. Obvious spatial differences in NH3 emissions were also observed, and high emissions were predominantly concentrated in North China. Further, NH3 emissions tended to be high in summer and low in winter, and the ratio for the July–January period was 3.08. Furthermore, maize and rice fertilization in summer was primarily responsible for the increase in NH3 emissions in China, and the evaluation of the spatial and temporal accuracy of the NH3 emission inventory established in this study using the WRF-Chem and ground station- and satellite-based observations showed that it was more accurate than other inventories.

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348 Integration of Nutrition with Air and Water Environmental Concerns

Journal of Animal Science ◽

10.1093/jas/skab235.352 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 195-195

Author(s):

Alan Rotz

Keyword(s):

Crop Production ◽

Water Footprint ◽

Production Systems ◽

Comprehensive Evaluation ◽

Cost Effective ◽

Mitigation Strategies ◽

Ammonia Emission ◽

Nitrogen And Phosphorus ◽

Nutrient Excretion ◽

Important Concern

Abstract The dairy and beef cattle industries face a number of environmental challenges related to air and water quality as well as the use of limited resources such as water and fossil energy. Mitigation strategies are available and being developed to reduce environmental impacts, but economical solutions remain a challenge. Assessment of mitigation strategies requires a comprehensive evaluation to assure that benefits in one component are not offset by harm in another. Process-based modeling and life cycle assessment provide tools for conducting this type of integrated evaluation. The most cost-effective strategies often begin with animal feeding. The diet of the animal affects resource use and nutrient excretion where the amount and form of nitrogen and phosphorus excreted affect air and water emissions. National assessments of the U.S. beef and dairy industries indicate where mitigation is most needed. Although greenhouse gas emissions receive most of the concern today, water consumption is another important concern, particularly for producers in drier regions such as the western United States. Over 90% of the water consumed in beef and dairy production is used in irrigated feed-crop production. Therefore, animal diets that use byproduct or other feeds not related to irrigated production can provide large reductions in the water footprint of beef and dairy products. Another emerging concern is that of ammonia emission where beef and dairy cattle may contribute more than half of the national emission inventory. Efficient protein feeding is the most economical and effective step that can be taken to reduce this environmental impact. Simulation of mitigation strategies using production system models provides comprehensive evaluation and prioritization among available and possible options, giving direction toward more sustainable ruminant animal production systems.

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