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Poultry farming generates significant poultry litter (broiler litter and laying hen manure), posing environmental and human health risks. Heat treatment, particularly through drying, can mitigate these adverse effects. This paper aimed to explore the impact of various drying methods of poultry litter on key process indicators. The literature review showed that the drying kinetics of the broiler litter in a hot air dryer is affected by the manure depth, air velocity, drying temperature, and air relative humidity. Nevertheless, the effect of the air relative humidity is insignificant on drying laying hen manure. Hot air drying, freeze drying, and oven drying have significant effects on the nutrient content of the broiler litter. In drying both broiler litter and laying hen manure, the specific energy consumption decreases as air temperature and relative humidity rise. Low temperatures cause poor bacteria destruction in poultry litter, but at temperatures over 50°C, Salmonella is completely destroyed. The ammonia release from laying hen manure and broiler litter is very sensitive to moisture content. Generally, air temperature, air velocity, manure depth, and air relative humidity positively correlate with ammonia emission. The average ammonia emission during belt drying of laying hen manure is about 209.3 mg NH3 d-1 hen-1. Finally, the lack of comprehensive research on poultry litter drying with modern drying methods (ultrasound, microwave, infrared rays, and freeze drying) is evident. One approach that may offer new opportunities is hybrid methods, such as a combination of dryers that use hot air drying agents with these modern drying methods.

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Advancement of the absorbent for CO2 capture is essential in optimizing the performance and reducing the negative environmental effects associated with this technology. Despite ammonia's promise as an absorbent, the volatility limits its practical application and creates potential environmental pollution. Therein, we assess various additives (amino acids, carbonates, and alkanolamines) for ammonia-based solvents using multi-stage circulation absorber from the viewpoints of aerosol emission, ammonia emission, and CO2 capture efficiency. Experimental findings reveal that ammonia volatilization can be inhibited by the protonation of free ammonia by carboxyl groups and the formation of hydrogen bonding between amino/hydroxyl groups and ammonia, with ammonia emission reduced by 21.7 %, aerosol emission reduced by 26.5 %, and CO2 capture efficiency increased to a maximum of 87.8 % under the condition of adding histidine. Moreover, the experiment highlights a positive correlation between total ammonia emission and aerosol concentration/diameter. Additionally, tests combining source abatement with water wash exhibit up to 50.5 % aerosol removal efficiency and up to 76.6 % ammonia removal efficiency. To further mitigate emissions, a comprehensive approach is proposed, achieving an 84.4 % reduction in ammonia emission and a 61.9 % reduction in aerosol emission. Finally, a method for recycling ammonia for desulfurization is suggested.

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Inevitably, aerobic biological treatment processes generate emissions of ammonia (NH3) and greenhouse gas (GHGs) emissions, especially nitrous oxide (N2O). The rapid bio-drying process (RBD) for food waste (FW) alleviates issues arising from its substantial growth. However, its emissions of NH3 and N2O remain unknown, and the correlation with nitrogen components in the substrate remains unclear, significantly impeding its widespread adoption. Here, the nitrogen loss and its mechanisms in RBD were investigated, and the results are as follows: The total emission of NH3 and N2O were1.42 and 1.16 mg/kg FW (fresh weight), respectively, achieving a 98 % reduction compared to prior studies. Structural equation modeling demonstrates that acid ammonium nitrogen (AN) decomposition chiefly generates NH3 in compost (p < 0.001). Strong correlation (p < 0.001) exists between amino acid nitrogen (AAN) and AN. In-depth analysis of microbial succession during the process reveals that the enrichment of Brevibacterium, Corynebacterium, Dietzia, Fastidiosipila, Lactobacillus, Mycobacterium, Peptoniphilus, and Truepera, are conducive to reducing the accumulation of AN and AAN in the substrate, minimizing NH3 emissions (p < 0.05). While Pseudomonas, Denitrobacterium, Nitrospira, and Bacillus are identified as key species contributing to N2O emissions during the process. Correlation analysis between physicochemical conditions and microbial succession in the system indicates that the moisture content and NO3- levels during the composting process provide suitable conditions for the growth of bacteria that contribute to NH3 and N2O emissions reduction, these enrichment in RBD process minimizing NH3 and N2O emissions. This study can offer crucial theoretical and data support for the resource utilization process of perishable organic solid waste, mitigating NH3 and GHGs emissions.

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This paper describes a model for the prediction of methane and ammonia emissions from fattening pig houses. This model was validated with continuous and discrete measurements using a reference method from two manure management systems (MMS): long storage (LS) in deep pits and short storage (SS) by daily flushing of a shallow pit with sloped walls and partial manure dilution. The average calculated methane and ammonia emissions corresponded well with the measured values. Based on the calculated and measured results, the average calculated CH4 emission (18.5 and 4.3 kg yr-1 per pig place) was in between the means from the continuous data from sensors (15.9 and 5.6 kg yr-1 per pig place) and the means from the discrete measurements using the reference method (22.0 and 3.1 kg yr-1 per pig place) for the LS and SS systems, respectively. The average calculated NH3 emission (2.6 and 1.4 kg yr-1 per pig place) corresponded well with the continuous data (2.6 and 1.2 kg yr-1 per pig place) and the discrete measurements using the reference method (2.7 and 1.0 kg yr-1 per pig place) from LS and SS, respectively. This model was able to predict the reduction potential for methane and ammonia emissions by the application of mitigation options. Furthermore, this model can be utilized as a predictive tool, enabling timely actions to be taken based on the emission prediction. The upgraded model with robust calculation rules, extensive validations, and a simplified interface can be a useful tool to assess the current situation and the impact of mitigation measures at the farm level.

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Most soil ammonia (NH3) emissions originate from soil nitrogen (N) that has been in the form of exchangeable ammonium. Emitted NH3 not only induces nutrient loss but also has adverse effects on the cycling of N and accelerates global warming. There is evidence that arbuscular mycorrhizal (AM) fungi can alleviate N loss by reducing N2O emissions in N-limited ecosystems, however, some studies have also found that global changes, such as warming and N deposition, can affect the growth and development of AM fungi and alter their functionality. Up to now, the impact of AM fungi on NH3 emissions, and whether global changes reduce the AM fungi's contribution to NH3 emissions reduction, has remained unclear. In this study, we examined how warming, N addition, and AM fungi alter NH3 emissions from high pH saline soils typical of a temperate meadow through a controlled microscopic experiment. The results showed that warming significantly increased soil NH3 emissions, but N addition and combined warming plus N addition had no impact. Inoculations with AM fungi strongly reduced NH3 emissions both under warming and N addition, but AM fungi effects were more pronounced under warming than following N addition. Inoculation with AM fungi reduced soil NH4+-N content and soil pH, and increased plant N content and soil net N mineralization rate while increasing the abundance of ammonia-oxidizing bacterial (AOB) gene. Structural equation modeling (SEM) shows that the regulation of NH3 emissions by AM fungi may be related to soil NH4+-N content and soil pH. These findings highlight that AM fungi can reduce N loss in the form of NH3 by increasing N turnover and uptake under global changes; thus, AM fungi play a vital role in alleviating the aggravation of N loss caused by global changes and in mitigating environmental pollution in the future.

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This study aimed to evaluate the benefits of using sawdust, pinewood shavings, and rubber wood shavings as horse bedding materials. Nine horses were used in a repeated measure design, where each horse was provided with each of the bedding materials for two consecutive weeks. The weight, cost, mucking out time, ammonia emissions, and urine holding capacity were measured and calculated for each bedding material. Results showed that pinewood shavings had the highest urine-holding capacity, while rubber wood shavings had the lowest absorbency for urine. Pinewood shavings also had lower ammonia emissions compared to sawdust and rubber wood shavings but were significantly more expensive. Sawdust was the cheapest of the three bedding materials, but it was used in greater quantities, which required more time for mucking out. The findings from this study could be used to make informed decisions on bedding materials for stables, taking into consideration the trade-off between cost, maintenance requirements, and labor hours.

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The type of litter material has direct impacts on production, behavioral, and welfare parameters of broilers. The price of conventionally-used litter materials is increasing. Salvinia molesta is a fast-growing aquatic plant which has become an environmental issue in some areas. This study assessed the suitability of air-dried Salvinia plants (SAL) as an alternate litter material to paddy husk (PH). Resulting in a completely randomized experiment, a total of 240 broilers was raised in 12 floor-pens each provided with either PH or SAL as litter materials, from 11 to 36 d. Scan sampling technique was employed to record the birds' engagement in 15 predetermined behaviors. Foot pad dermatitis (FPD), hock burn damage (HBD) and plumage cleanliness (PC) were assessed using Welfare Quality Scoring System. Litter samples were analyzed for pH, dry matter%, water holding capacity, porosity, N%, tapped-density and ammonia emission rate. The litter material had no significant effect (P > 0.05) on mortality, growth performance parameters, dressing % and visceral organ weight. The scores for FPD and PC were unaffected by the litter materials. SAL litter reported significantly lower (P < 0.05) HBD scores. The percentages of birds engaged in eating and wing flapping behaviors were significantly lower on SAL. Litter type had no significant influence on the color, aroma, flavor, texture and overall acceptability of breast meat. Air-dried Salvinia plants reported acidic pH. SAL litter gave a significantly higher tapped-density. Ammonia emission rate of SAL litter was significantly lower than that of PH. However, the final litter N content was higher for PH (3.7%) than SAL (3.2%). The study proposes air-dried Salvinia plants as a litter material for broilers since it gives growth performance comparable to PH with reduced hock burn damage incidences. Effects of SAL on behavior and the fertilizer value of the spent litter are to be studied further.

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Over the years, different solutions were developed and tested to reduce the emissions of ammonia and particulate matter from the livestock facilities. The environmental performances of these solutions were not always evaluated in detail. This study examines the environmental footprint of pig production at farm gate, with a focus on emissions from housing. Using Life Cycle Assessment, the environmental impact of pig production in a transition farm in Spain and in two finishing farms in Italy was evaluated considering three scenarios (one baseline and two of them involving an air treatment technology: wet scrubber or dry scrubber). The study goal was to quantify the environmental footprint of pig production in different scenarios, identify key environmental hotspots, and to assess impact reduction efficiency due to the two assessed technologies, analyze the environmental trade-offs that come with the use of these technologies, and identify potential for improvements. Both wet and dry scrubbers showed potential for reducing emissions in pig housing, affecting environmental impact categories related to air pollutants such as particulate matter, acidification and eutrophication. However, there were trade-offs between emissions reduction and categories related to energy and resource use. The infrastructure and consumables required to operate the scrubber added to the impacts compared to the baseline. The dry scrubber showed a more favorable balance between emission reduction and trade-offs. In this regard, results were similar for the Spanish and Italian farms, although there were slight variations. Scrubbers had a greater effect in the Italian farms due to their use along longer periods of the pig fattening (closed cycle farms) compared to the Spanish farm (transition farm). Scrubbers are environmentally promising, especially where acidification, eutrophication and particulate matter are local problems. However, they alone cannot fully address the complex environmental impacts of pig production, which require comprehensive interventions across the supply chain.

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As a typical industrial and agricultural province, Shandong is one of China's most seriously air-polluted regions. One comprehensive ammonia emission inventory with a high spatial resolution (1 km × 1 km) for 136 county-level administrative divisions in Shandong from 2000 to 2020 is developed based on county-level activity data with the corrected and updated emission factors of seventy-seven subcategories. Annual ammonia emissions decrease from 1003.3 Gg in 2000 to 795.9 Gg in 2020, with an annual decrease rate of 1.2 %. Therein, the ammonia emissions associated with livestock and farmland ecosystems in 2020 account for 50.8 % and 32.9 % of the provincial total ammonia emission, respectively. Laying hen and wheat are the livestock and crop with the highest ammonia emissions, accounting for 23.3 % and 36.3 % of ammonia emissions from livestock and the application of synthetic fertilizers, respectively. Furthermore, waste treatment, humans and vehicles are the top three ammonia emission sources in urban areas, accounting for 5.0 %, 4.7 % and 1.3 % of total ammonia emissions, respectively. The spatial distribution of grids with high ammonia emissions is consistent with the distribution of intensive farms. Significant emission intensity areas mainly concentrate in western Shandong (e.g., Caoxian of Heze, Qihe of Dezhou, Yanggu of Liaocheng, Liangshan of Jining) due to the large area of arable land and the high levels of agricultural activity. Overall, prominent seasonal variability characteristics of ammonia emission are observed. Ammonia emissions tend to be high in summer and low in winter, and the August to January-emission ratio is 5.6. The high temperature and fertilization for maize are primarily responsible for Shandong's increase in ammonia emissions in summer. Finally, the validity of the estimates is further evaluated using uncertainty analysis and comparison with previous studies. This study can provide information to determine preferentially effective PM2.5 control strategies.

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Management of nitrogen (N) fertilizer is a critical factor that can improve maize (Zea mays L.) production. On the other hand, high volatilization losses of N also pollute the air. A field experiment was established using a silt clay soil to examine the effect of sulfur-coated urea and sulfur from gypsum on ammonia (NH3) emission, N use efficiency (NUE), and the productivity of maize crop under alkaline calcareous soil. The experimental design was a randomized complete block (RCBD) with seven treatments in three replicates: control with no N, urea150 alone (150 kg N ha-1), urea200 alone (200 kg N ha-1), urea150 + S (60 kg ha-1 S from gypsum), urea200 + S, SCU150 (sulfur-coated urea) and SCU200. The results showed that the urea150 + S and urea200 + S significantly reduced the total NH3 by (58 and 42%) as compared with the sole application urea200. The NH3 emission reduced further in the treatment with SCU150 and SCU200 by 74 and 65%, respectively, compared to the treatment with urea200. The maize plant biomass, grain yield, and total N uptake enhanced by 5-14%, 4-17%, and 7-13, respectively, in the treatments with urea150 + s and urea200 + S, relative to the treatment with urea200 alone. Biomass, grain yield, and total N uptake further increased significantly by 22-30%, 25-28%, and 26-31%, respectively, in the treatments with SCU150 and SCU200, relative to the treatment with urea200 alone. The applications of SCU150 enhanced the nitrogen use efficiency (NUE) by (72%) and SCU200 by (62%) respectively, compared with the sole application of urea200 alone. In conclusion, applying S-coated urea at a lower rate of 150 kg N ha-1 compared with a higher rate of 200 kg N ha-1 may be an effective way to reduce N fertilizer application rate and mitigate NH3 emission, improve NUE, and increase maize yield. More investigations are suggested under different soil textures and climatic conditions to declare S-coated urea at 150 kg N ha-1 as the best application rate for maize to enhance maize growth and yield.

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Setting nitrogen (N) emission targets for agricultural systems is crucial to prevent to air and groundwater pollution, yet such targets are rarely defined at the county level. In this study, we employed a forecasting-and-back casting approach to establish human health-based nitrogen targets for air and groundwater quality in Quzhou county, located in the North China Plain. By adopting the World Health Organization (WHO) phase I standard for PM2.5 concentration (35 µg m-3) and a standard of 11.3 mg NO3--N L-1 for nitrate in drinking water, we found that ammonia (NH3) emissions from the entire county must be reduced by at least 3.2 kilotons year-1 in 2050 to meet the WHO's PM2.5 phase I standard. Additionally, controlling other pollutants such as sulfur dioxide (SO2) and nitrogen oxides (NOx) is necessary, with required reductions ranging from 16% to 64% during 2017-2050. Furthermore, to meet the groundwater quality standard, nitrate nitrogen (NO3--N) leaching to groundwater should not exceed 0.8 kilotons year-1 by 2050. Achieving this target would require a 50% reduction in NH3 emissions and a 21% reduction in NO3--N leaching from agriculture in Quzhou in 2050 compared to their respective levels in 2017 (5.0 and 2.1 kilotons, respectively). Our developed method and the resulting N emission targets can support the development of environmentally-friendly agriculture by facilitating the design of control strategies to minimize agricultural N losses.

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Probiotic supplementation has become a prominent method of decreasing ammonia emissions in poultry production. The present study was conducted to investigate the influence of Lactobacillus plantarum on ammonia emission, immune responses, antioxidant capacity, cecal microflora and short chain fatty acids, and serum metabolites in broilers challenged with ammonia. A total of 360 1-day-old yellow-feathered broilers were randomly divided into three treatment groups: birds fed with a basal diet (CON), a basal diet supplemented with ammonia (AN), and a basal diet supplemented with 2.5 × 108 CFU L. plantarum kg-1 and challenged with ammonia (LP). Data showed that L. plantarum supplementation decreased ammonia more than 30% from day 48, and significantly reduced the levels of serum urea nitrogen and ammonia, fecal urease, and ammonium nitrogen compared with those on CON. Compared with AN and CON treatments, LP administration increased (p < 0.05) the concentration of serum immunoglobulin Y (IgY), IgM, and IL-10, as well as the serum total-antioxidant capacity (T-AOC) and GSH-Px, and decreased (p < 0.05) IL-1ß, IL-6, and TNF-α. Furthermore, birds supplemented with LP had higher (p < 0.05) cecal contents of short chain fatty acids (SCFAs) than AN birds and had more butyrate than CON birds. Data from 16s high throughput sequencing showed that LP supplementation significantly increased (p < 0.05) the Shannon and Simpson indices of bird cecal microflora, and Alloprevotella dominated the LP birds. The function prediction of cecal microflora indicated that LP treatment significantly increased alanine aspartate and glutamate metabolism, starch and sucrose metabolism, exosome, mismatch repair, homologous recombination, DNA repair and recombination proteins, and amino acid-related enzymes. The serum metabolome showed that LP supplementation significantly changed the aminoacyl-tRNA, pantothenate and acetyl-coenzyme A, arginine, phenylalanine, tyrosine and tryptophan, valine, leucine, and isoleucine biosynthesis; purine, beta-alanine, galactose, histidine, alanine, aspartate and glutamate, glyoxylate and dicarboxylate, pyruvate and thiamine metabolism, melanogenesis, and citrate cycle.

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There is an urgent need for accurate measurement for emissions of ammonia (NH3) and hydrogen sulfide (H2S) in dairy barns in order to obtain reliable emission inventories and to develop and evaluate abatement strategies. This experiment was performed on three dairy farms in central China during 14 consecutive days in the winter 2020. Concentrations of NH3 and H2S were measured every two hours. The samples were taken inside and outside of barns from 7 sites at two heights (at floor and 1.5 over the floor). The results show that the average NH3 concentration was 2.47 mg/m3 with a maximum of 4.62 mg/m3, while the average H2S concentration was 0.179 mg/m3 with a maximum of 0.246 mg/m3. Lactating cows produced significantly more NH3 (3.73 mg/m3 versus 2.34 mg/m3) and H2S (0.24 mg/m3 versus 0.14 mg/m3) than non-lactating cows. NH3 and H2S concentrations were higher at 0 m than at 1.5 m, especially during the day. In addition, the average daily emission rates per animal unit (AU = 500 kg weight) were 23.5 g and 0.21 g for NH3 and H2S, respectively. The emission rate for NH3 was then used to extrapolate the NH3 emission from the Chinese dairy production. Our estimation for 2016 was 0.45 Tg, and it could reach 1.35 Tg by 2050. These numbers reflected our first attempt to calculate emission inventories for the Chinese dairy industry. Our results also suggest that more concrete measures must be taken to reduce the uncertainties of NH3 emissions from dairy cow production in China.

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This study aimed to evaluate trade-offs between enteric and manure CH4 emissions, and the size of synergistic effects for CH4 and nitrogenous emissions (NH3 and N2O). Sixty-four Holstein-Friesian cows were blocked in groups of 4 based on parity, lactation stage, and milk yield. Cows within a block were randomly allocated to a dietary sequence in a crossover design with a grass silage-based diet (GS) and a corn silage-based diet (CS). The GS diet consisted of 50% grass silage and 50% concentrate, and CS consisted of 10% grass silage, 40% corn silage, and 50% concentrate (dry matter basis). The composition of the concentrate was identical for both diets. Cows were housed in groups of 16 animals, in 4 mechanically ventilated barn units for independent emission measurement. Treatment periods were composed of a 2-wk adaptation period followed by a 5-wk measurement period, 1 wk of which was without cows to allow separation of enteric and manure emissions. In each barn unit, ventilation rates and concentrations of CH4, CO2, NH3, and N2O in incoming and outgoing air were measured. Cow excretion of organic matter was higher for CS compared with GS. Enteric CH4 and cow-associated NH3 and N2O emissions (i.e., manure emissions excluded) were lower for CS compared with GS (-11, -40, and -45%, respectively). The CH4 and N2O emissions from stored manure (i.e., in absence of cows) were not affected by diet, whereas that of NH3 emission tended to be lower for CS compared with GS. In conclusion, there was no trade-off between enteric and manure CH4 emissions, and there were synergistic effects for CH4 and nitrogenous emissions when grass silage was exchanged for corn silage, without balancing the diets for crude protein content, in this short-term study.

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Understanding the costs of emission abatement measures is essential for devising reduction efforts. It allows to identify cost-effective solutions to achieve target values set by international agreements or national policies. This work aims to summarize and discuss the current knowledge on costs and effects associated with selected ammonia (NH3) mitigation measures in livestock production through comparison of country-specific and model-estimated values. Often, large differences appear between the results of individual countries, also in comparison with model results that are generally better harmonized between countries. It seems that different system boundaries in cost assessments, but also different geographic and structural conditions create perceived as well as real cost differences, also caused by the variability of individual situations. Our results are robust with respect to identifying feeding strategies as the most cost-effective, but results for other mitigation options do not show any clear trends, thus making it difficult to distinguish further cost-effective solutions. We point out and discuss some key aspects which may affect estimates of national costs, leading to challenges with the interpretation of final results. Our study concludes that further and more consistent assessments (e.g. standardized protocols) are needed to improve the evaluation base for other individual abatement options, including options that are under development.

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Ammonia emissions from motor vehicles have great effect on air pollution and human health in urban areas. Recently, many countries have focus on ammonia emission measurement and control technologies for light-duty gasoline vehicles (LDGVs). To analyze ammonia emission characteristics, three conventional LDGVs and one hybrid electric light-duty vehicle (HEV) were evaluated over different driving cycles. The average ammonia emission factor at 23℃ was 4.5 ± 1.6 mg/km over Worldwide harmonized light vehicles test cycle (WLTC). Most ammonia emissions mainly concentrated in low and medium speed sections at cold-start stage, which were related to rich burn conditions. The increasing ambient temperatures led to the decrease of ammonia emissions, but high load caused by extremely elevated ambient temperature led to obvious ammonia emissions. The ammonia formation is also related to three-way catalytic converter (TWC) temperatures, and underfloor TWC catalyst could eliminate ammonia partly. The ammonia emission from HEV, which are significant less than LDGV, corresponded to the engine working state. The large temperature difference in the catalysts caused by power source shifts were the main reason. Exploring the effects of various factors on the ammonia emission is beneficial for revealing the instinct formation conditions, providing theoretical support for the future regulations.

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This study reports on the field testing of a newly and originally designed laser absorption spectroscopy chamber (LASC) system based on closed dynamic chamber method, which is well suited for multi-point synchronous measurement of ammonia emissions in field multiple plot experiment. Main design feature of the LASC system is individual multi-reflection cells for each chamber, achieving the synchronous in-situ monitoring ammonia emissions of all the chambers. Two movable covers for automated opening and closing of the chamber, and the highly transparent chamber walls made of acrylic plate minimize the disturbance of the chamber deployment on the ammonia transport process in the chamber. Controlled field assessment experiment was conducted to evaluate the applicability and reliability of the LASC system. The results indicated that the optimum time length of chamber closure for monitoring ammonia emission is 3 min, and the appropriate time length of chamber ventilation is 17 to 37 min. The LASC system has higher accuracy for measuring ammonia emission rate and reliability for comparatively measuring ammonia emissions from different treatments than the traditional chamber methods.

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Agriculture produces food, fiber and biofuels for the world's growing population, however, agriculture can be a major contributor of nitrogen (N) losses including emissions of ammonia (NH3), nitrous oxide (N2O) and nitrate (NO3-) leaching and runoff. A Canadian Agricultural Nitrogen Budget for Reactive N (CANBNr) model was developed to estimate the soil N balance in 3487 soil landscape of Canada polygons from 1981 to 2016. The CANBNr model integrates NH3 emission from fertilizers, manure from housing, storage and field, as well as direct/indirect N2O emissions from fertilizers, manures, crop residues and soil organic matter. The NO3- leaching is estimated based on the residual soil N (RSN) at harvest and drainage derived with the DeNitrification-DeComposition (DNDC) model. From 1981 to 2016, the N input from fertilizer and N fixation increased at a greater rate than N removal in harvested crops in all provinces of Canada, resulting in an increase in the RSN and N losses. In 2016, the Prairie provinces had lower N losses (11.7 kg N ha-1) from N2O, NH3 and NO3- compared with 43.2 kg N ha-1 in central Canada, and 76.5 kg N ha-1 in Atlantic Canada. However, the Prairie provinces had 84.3% of the total Canadian farmland (74.3% of the total Canadian N input), while central Canada had 12.9% of Canadian farmland (21.7% of the total Canadian N input). In the Prairie provinces, the total N2O loss from fertilizer N ranged 4.4-8.6 Gg N whereas NH3 loss ranged from 17.1 to 44.6 Gg N and these values were influenced by both emission intensity and total land area. Total N2O losses from manure were highest in Alberta, Ontario and Quebec resulting in 4.8, 4.4, and 3.4 Gg N and NH3 losses from manure were also highest in these 3 provinces at 61.1, 45.2 and 40.4 Gg N, respectively. Nitrate leaching was impacted by drainage volumes, soil type and N inputs. In the non-growing season, NO3- leaching losses (36-yr average) were 63.3 Gg in Ontario and 57.5 Gg N in Quebec compared with 20.8 Gg N for Ontario and 35.5 Gg N for Quebec in the growing season. In contrast, the Prairie provinces showed higher NO3- leaching in the growing season (23.1-37.4 Gg N) than in the non-growing season (10.4-13.7 Gg N). In summary, total fertilizer N increased the most over the 36 years in the Prairies which resulted in increased RSN and N leaching losses that will require further intervention.

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The objective of this research was to determine whether diet composition, or adding probiotic or symbiotic feed additives to broiler diets can modify the N composition of the excreta and the dynamics of ammonia volatilization from the manure. A total of 574 one-day-old Ross 308 broiler chickens were fed four different diets. The treatments included a corn and soybean meal-based control diets (C), wheat-based and wheat bran containing diets (W), a multi-strain probiotic treatment (Broilact®; Br), and a symbiotic additive containing Bacillus subtilis, inulin, and Saccharomices cerevisiae (Sy). Feeding the wheat-based diet significantly improved the weight gain and FCR of chickens. Treatment W also significantly increased the dry matter content of the excreta compared with the probiotic and symbiotic treatments. Both Br and Sy tended to decrease the amount of excreted uric acid, which is the main substrate of ammonia. Treatment Sy reduced the urinary N ratio of the excreta in comparison with treatment W. The symbiotic additive resulted in significantly higher ammonia emission in the first two hours. On the other hand, the dynamics of the emission was slow at the beginning and increased steeply after 15 h when the wheat-based diets were fed. Based on our results, the wheat-based diets, containing soluble arabinoxylans, and the symbiotic treatments of broiler diets have an impact on the urinary and faecal nitrogen composition of the excreta, and also on the dynamics of ammonia release from the manure.

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The odor emission such as ammonia (NH3) and hydrogen sulfide (H2S) during the composting process is a severe problem that adversely affects the environment and human health. Therefore, this study aimed to (1) evaluate the variation of physicochemical characteristics during the co-composting of food waste, and sawdust mixed biochar; (2) assess the efficiency of biochar-composting combined amendment materials for reducing odor emissions and their maturity. The raw materials including food waste (FW), straw dust (SD), and biochar (BC) were prepared and homogeneously mixed with the weight ranging from 120.0 kg to 135.8 kg with five treatments, BC0 (Control), BC1 (5 % biochar), BC2 (5 % distilled water washed biochar), BC3 (10 % biochar), BC4 (20 % biochar). Adding biochar could change physicochemical properties such as temperature, moisture, and pH during composting. The results indicated applying biochar-composting covering to minimalized NH3 and H2S aided by higher porous structure and surface functional groups. Among trials, biochar 20 % obtained the lowest NH3 (2 ppm) and H2S (3 ppm) emission on day 16 and stopping their emission on day 17. The NH3/NH4+ adsorption on large specific surface areas and highly porous micro-structure of biochar lead to reduced nitrogen losses, while nitrification (NH4+ ➔ NO2- ➔ NO3-) may also contribute to nitrogen retention. The H2S concentration decreased with increasing the biochar proportion, suggesting that biochar could reduce the H2S emission. Correlation analysis illustrated that temperature, moisture, and oxygen are the most critical factors affecting H2S and NH3 emissions (p <0.05). The physicochemical properties and seed germination index indicated that the compost was mature without phytotoxicity. These novelty findings illustrated that the biochar amendment is an effective solution to reduce odor emission and enhances the maturity of compost mixture, which is promising to approach in real-scale conditions and could apply in agricultural fields.

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