Ammonia Volatilization Losses Research Articles

The application of nano−clinoptilolite based nitrogen fertilizer mixed with urea promotes nitrogen balance and enhances economic and ecological benefits in paddy fields

Reducing the size of clinoptilolite accentuates its structural attributes, notably mesoporosity and the silica−aluminum ratio, which enhanced its capabilities as an efficient adsorbent and modifier. This research aims to utilize the augmented small−size effect of clinoptilolite to develop a high−performance nano−clinoptilolite based nitrogen (N) fertilizer, to substitute an equivalent amount of urea. To this end, a two−year field experiment was conducted using a single−factor randomized complete block design, involving five different nano−clinoptilolite based N fertilizer mixed with urea (ZN) ratios: control treatment (100% Urea, CK); 20% Z & 80% Urea (Z2N8); 30% Z & 70% Urea (Z3N7); 40% Z & 60% Urea (Z4N6); 50% Z & 50% Urea (Z5N5). This study explored the effects of ZN on ammonia volatilization (AV), N runoff loss, N accumulation, N balance, yield, and ecological benefits in paddy fields. The results showed that Z2N8, Z3N7, Z4N6, and Z5N5 reduced the total AV losses by 8.57%, 20.52%, 30.20%, and 37.13% (two−year average), and reduced runoff losses by 23.29%, 29.93%, 39.66%, and 43.76%, respectively. Additionally, Z2N8, Z3N7, Z4N6, and Z5N5 increased whole−plant N accumulation by 24.32%, 16.84%, 9.00%, 4.85%, and raised rice yield by 15.28%, 10.28%, 6.99%, 5.05%, respectively. This result indicates that ZN can enhance N utilization, although the effectiveness diminishes with an increased application ratio. Furthermore, Z2N8, Z3N7, and Z4N6 lowered N surpluses by 48.77%, 25.84%, and 3.17%, respectively, while Z5N5 resulted in an increase in N surplus by 9.61% relative to the control. Compared to CK, nano−clinoptilolite based N fertilizer replacing 20% of urea (Z2N8) increased income by 14.75%, reduced environmental damage cost by 8.77%, and ultimately boosted net economic benefits by 5.33% and net economic and ecological benefits by 5.75%. In conclusion, Z2N8 can be contemplated as a compound fertilizer to be applied to farmland to enhance both economic and ecological benefits.

Ammonia volatilization measured with the IHF method in a rainfed arable crop: Evaluation of tillage intensity and the number of experimental replicates

Ammonia (NH3) volatilization losses have severe impacts on human health, climate change and natural environments, but the effect of tillage intensity on these emissions has been barely evaluated in field conditions, particularly using micrometeorological methods, which require large surfaces. In this context, a field experiment in a barley (Hordeum vulgare L.) crop was set up in central Spain, in which NH3 volatilization losses from non-tilled plots (NT) were compared with those from conventionally tilled (T) plots, using the integrated horizontal flux (IHF) technique with three replicates. Ancillary soil and meteorological measurements were taken to explain NH3 fluxes, and the effect of the number of replicates on the results was statistically addressed. The highest NH3 emissions were obtained in NT plots after both basal (40 kg N ha−1 applied as urea) and top-dressing (120 kg N ha−1 applied as urea) fertilization events, while NH3 emission factors were higher after basal fertilization, in comparison with top-dressing application. Considering the sum of both periods, NT significantly increased NH3 emissions by 63 % with respect to T. We observed a notable influence of the number of replicates, since only two of the nine combinations of two replicates led to rejecting the null hypotheses. No tillage requires the optimized management of N (timing, rate and particularly source) to abate the potential side effects regarding NH3 volatilization, while the use of robust measurement methods (e.g. IHF) should be implemented with enough replicates to increase the precision in estimating differences.

N-loaded clinoptilolite under water-saving irrigation mitigates ammonia volatilization while increasing grain yield and water-nitrogen use efficiency

Minimizing ammonia volatilization (AV) in paddy fields can not only reduce nitrogen (N) loss but also prevent environmental pollution. While clinoptilolite has been shown to effectively decrease AV, it is important to note that natural clinoptilolite contains non-desorption active sites that can hinder soil N effectiveness, ultimately leading to decreased N utilization. Therefore, we proposed modifying clinoptilolite with a weakly acidic NH4Cl solution (N-loaded clinoptilolite, NZ) to replenish exogenous N while continuously reducing AV. A lysimeter experiment was conducted under two irrigation regimes (ICF: continuous flooding irrigation; IAWD: alternate wet-dry irrigation) to examine the effect of N-loaded clinoptilolite on soil N, water-N use, AV loss and grain yield over two rice-growing seasons in Northeast China. The results show that AWD significantly reduced AV during the basal fertilization period and the first top-dressing period in 2020 and 2021. Compared with the control (without N-loaded clinoptilolite), N-loaded clinoptilolite at 10 t·ha−1 (NZ10) significantly reduced the total AV by 29% and 33% in the two years, respectively, with the most significant reduction impact (30% and 36%) occurring in the first top-dressing period. NZ10 coupled with AWD regime reduced AV more significantly and compared with conventional management (ICFNZ0), IAWDNZ10 decreased the total amount of AV by 36% and 42% in two years, respectively. N-loaded clinoptilolite also increased the soil NH4+-N and NO3--N content during the tillering and grain-filling stages of rice, which in turn increased the rate of maximum N accumulation, shortened the duration, promoted N accumulation and translocation in rice plants, and finally reduced AV. Additionally, when compared to the control, the utilization of NZ10 under the AWD irrigation regime resulted in an average 29% reduction in irrigation water usage and a yield increase of 5% over two years. Thus, IAWDNZ10 was not only highly productive and water-efficient but also significantly reduced AV, making it an environmentally friendly and effective management model for on-farm practices.

Controlled-Release Blended Fertilizer Combined with Urea Reduces Nitrogen Losses by Runoff and Improves Nitrogen Use Efficiency and Yield of Wet Direct-Seeded Rice in Central China

Controlled-release fertilizer is one of the best fertilizer management strategies for improving the yield and nitrogen use efficiency of transplanted seedling rice. Wet direct-seeded rice has gradually replaced transplanted seedling rice since it saves labor. In addition, it is conducive to mechanization promotion. However, the effects of controlled-release fertilizers on wet direct-seeded rice remain largely unknown. A two-year field experiment aimed to compare the effects of controlled-release blended fertilizer at two rates (basal N to tiller N ratio = 7:3 (CRBF+U), CRBF alone), urea at two rates (basal–tiller ratio of 4:6 (U40), 6:4 (U60)) and a control (no N fertilizer) on the ammonia volatilization (AV) loss, nitrogen runoff loss, accumulation, transport, utilization and yield of rice. The nitrogen runoff loss in wet direct-seeded rice paddy fields was concentrated from sowing to the three-leaf and one-leaflet stage, and the loss rat was lowest after CRBF+U (11.41–12.94%). AV loss rate was lowest after CRBF (3.41%), followed by CRBF+U (3.55–3.89%). CRBF+U increased nitrogen accumulation by extending the duration of rapid nitrogen growth and accelerating maximum nitrogen growth. CRBF+U also increased the nitrogen transport rate of stems, sheaths and leaves from full heading to maturity, and intensified the increase in nitrogen in panicles, increasing the harvest index, agronomy utilization rate and apparent utilization rate of nitrogen. Finally, the grain number per panicle, seed-setting rate and actual yield of rice were significantly improved. In conclusion, CRBF+U can reduce nitrogen runoff loss and AV loss and can improve the yield and nitrogen use efficiency of wet direct-seeded rice.

Evaluation of passive flux samplers with different orifice sizes to measure ammonia volatilization losses

AbstractA common passive sampler used to measure NH3 volatilization losses in field studies has a nozzle with a 1‐mm, round orifice that reduces air flow to increase NH3 adsorption. This reduction in air flow, measured by the orifice's K value (0–1), implies a reduction in the amount of NH3 entering the sampler per unit of time, which may require a longer exposure to accumulate measurable quantities of NH3. Increasing the diameter of the orifice would increase the NH3 entering the sampler and possibly allow shorter exposure times, but it may also lead to increased NH3 bypass. The objectives of this research were to (1) determine the effect of wind speed on NH3 bypass in samplers with 1‐ or 2‐mm orifices, (2) determine the reduction in air speed in samplers with 1‐ or 2‐mm orifices by determining their K values, and (3) compare field NH3 volatilization losses measured with 1‐ and 2‐mm orifices. A laboratory study with wind speeds ranging from 0.6 to 10 m·s−1 showed that both orifice sizes had NH3 bypass at low and high wind speeds. Results from wind tunnel studies determined that flow was reduced to 63% (K = 0.63) in 1‐mm orifices and to 74% (K = 0.74) in 2‐mm orifices. Field studies indicated that 1‐mm orifices may measure greater NH3 volatilization losses than 2‐mm orifices at average low wind speeds when maximum wind speeds <10 m·s−1, but may measure equal or lower losses than 2‐mm orifices when several days occur with maximum wind speeds >10 m·s−1.

Effects of the Combining Straw Return with Urease Inhibitor on Ammonia Volatilization, Nitrogen Use Efficiency, and Rice Yield in Purple Soil Areas.

Straw return in rice (Oryza sativa L.) paddy has been heavily criticized for its potential to influence ammonia (NH3) volatilization loss due to irrational fertilizer N application. Therefore, improving the N fertilization strategies within residue straw systems is necessary to reduce N loss from NH3 volatilization. This study investigated how the incorporation of oilseed rape straw and the urease inhibitor affected NH3 volatilization, fertilizer N use efficiency (FNUE), and rice yields over two growing seasons (2018-2019) in the purple soil region. This study arranged eight treatments combined straw (2, 5, 8 ton ha-1, named 2S, 5S, 8S, respectively), with urea or urease inhibitor (UI, 1% NBPT) with three replicates, which included control (CK), UR (Urea, 150 kg N ha-1), UR + 2S, UR + 5S, UR + 8S, UR + 2S + UI, UR + 5S + UI, UR + 8S + UI, based on the randomized complete block method. Our results indicated that incorporating oilseed rape straw increased NH3 losses by 3.2-30.4% in 2018 and 4.3-17.6% in 2019 than the UR treatment, attributing to the higher NH4+-N content and pH value within floodwater. However, the UR + 2S + UI, UR + 5S + UI and UR + 8S + UI treatments reduced NH3 losses by 3.8%, 30.3%, and 8.1% in 2018 and 19.9%, 39.5%, and 35.8% in 2019, separately compared to their corresponding UR plus straw treatments. According to the findings, adding 1% NBPT significantly decreased NH3 losses while incorporating 5 ton ha-1 oilseed rape straw. Furthermore, adding straw, either alone or in conjunction with 1% NBPT, increased rice yield and FNUE by 0.6-18.8% and 0.6-18.8%, respectively. Otherwise, NH3 losses scaled by yield in the UR + 5S + UI treatment decreased significantly between all treatments in 2018 and 2019. These results suggest that optimizing the oilseed rape straw rate combined with 1% NBPT applied with urea efficiently increased rice yield and reduced NH3 emissions in the purple soil region of Sichuan Province, China.

Ammonia loss potential and mitigation options in a wheat-maize rotation system in the North China Plain: A data synthesis and field evaluation

The North China Plain (NCP) is an intensive agricultural area and ammonia (NH3) emission hotspot in China. Urgent mitigation actions are needed to reduce its environmental impact. A field trial was conducted, and results combined with a synthesis of existing data to assess the NH3 loss and mitigation potentials in a wheat-maize double-crop rotation, a dominant crop production system in the NCP. Ammonia volatilization losses from N fertilizer applied to summer maize and winter wheat were 9.1% and 5.0%, respectively, based on the data synthesis, and were significantly affected by fertilizer application method and N fertilizer type. From the field trial, optimized reduction in N application rate, compared with conventional practice, had great efficiency for NH3 mitigation. Despite their high NH3 reduction potential, the higher input costs associated with the use of controlled-release fertilizers, replacement of urea with calcium ammonium nitrate or inclusion of double inhibitors (urease and nitrification inhibitors) with urea limited their applicability from an economic perspective. The inclusion of a urease inhibitor with urea achieved over 70% reduction in NH3 emission and also gave a significant improvement in grain yield, net income and N use efficiency. Future adoption of NH3 mitigation options in the NCP should focus on establishing a reduction target and consider the cost-benefits of simultaneous implementation of multiple mitigation techniques.

Comparison of ammonia‐N volatilization losses from untreated granular urea and granular urea treated with NutriSphere‐N®

AbstractDevelopment of novel methods to inhibit ammonia (NH3) volatilization losses has become a strong research focus to reduce the environmental impact of agriculture and as a potential area for growth in the fertilizer industry. European Union legislation on the regulation of NH3 emission from mineral fertilizers after 2030, will only allow urea fertilizers with reduced NH3 emissions by at least 30% to remain in use. The recent increase in fertilizer prices has also created a renewed impetus to curb these losses. This paper details the results of an experiment comparing the rates of volatilization from granular urea treated with NutriSphere‐N®, untreated urea and an unfertilized control as well as placing the results in context by conducting a review of similar studies featuring NutriSphere‐N®. The study was conducted in a light and temperature‐controlled growth chamber using the chamber built in air flow which collected any NH3 volatilized from a flask containing fresh soil with applied treatment and transported the NH3 to an acid trap where the volatilized NH3 was captured and exhaust air was removed. The experiment ran for 3 weeks and resulting samples were analysed colorimetrically and adjusted for differences in airflow. The temporal results show that urea dominated the flux profile but the pattern of fluxes from the two fertilizer N treatments were similar. When analysed cumulatively over the duration of the experiment, the fluxes from the NutriSphere‐N® treated urea were significantly (p = .018) (86%) lower than untreated urea and were not significantly different from the untreated control (p = .959).

Value-Added Fertilizers Enhanced Growth, Yield and Nutrient Use Efficiency through Reduced Ammonia Volatilization Losses under Maize–Rice Cropping Cultivation

Plant nutrition is an essential element for crop production and enormous amounts of fertilizers are used in agricultural systems. However, these sources emit toxic gasses and compounds in the environment that not only deteriorate soil quality but also cause a reduction in the use efficiency of applied nutrients. Therefore, the value addition of these fertilizer sources by coating micronutrients, microbes, polymers or other organic and inorganic compounds have been advocated recently. The present study aimed to evaluate the effectiveness of value-added fertilizer sources for growth and yield improvement of Zea mays (Pioneer-30T60) and Oryza sativa (Super Basmati-515) with a reduction in ammonia volatilization and an improvement in nutrient recovery by crop grains. Different phosphorus (P), potassium (K) and nitrogen (N) fertilizer sources (Di-ammonium phosphate (DAP), polymer coated DAP, zarkhez plus NPK, urea, polymer-coated urea and zabardast urea) were used in different combinations keeping one control for N. The results revealed that maximum growth, yield and nutrient recovery was shown by polymer-coated urea and DAP followed by zarkhez plus NPK and zabardast urea. Moreover, a minimum ammonia emission was recorded by polymer-coated fertilizers, but other value-added fertilizers were found inefficient in reducing ammonia emission, though these sources improved all growth and yield attributes. Nutrient recovery efficiency was patterned as; polymer coated fertilizers > zarkhez plus NPK + zabardast urea > zarkhez plus NPK + urea > DAP + zabardast urea > DAP + urea > DAP. Thus, the use of polymer-coated fertilizers was beneficial for both the reduction in ammonia volatilization and for improving nutrient use efficiency with maximum crop benefits.

Improving spring maize yield while mitigating nitrogen losses under film mulching system by right fertilization and planting placement

Efficient agronomic management strategies, such as “4 R” fertilization techniques combined with rational agronomic practices, are crucial options to overcome the challenge of increasing yields while mitigating environmental hazards. A three-year (2019–2021) field trial was carried out to screen for the right fertilization and planting placement that is suitable for labor-saving and mechanical cultivation practices. Fertilization placement [nitrogen (N) fertilizer was deep applied under the film-mulched band (FM) and in the un-mulched zone (FuM)] and planting placement [seeds were sowed in the film-mulched band (PM) and un-mulched zone (PuM)] were assigned as the main plots and split plots, separately, in a split-plot design. So, there were four treatments (FM-PM, FM-PuM, FuM-PM, and FuM-PuM). The yield, carbon and N accumulation and translocation, root traits and their spatial distribution with soil mineral N, soil N loss, etc., were examined. Results showed that the grain yield of FM and PuM was significantly higher by 10.7 % and 8.8 % than that of FuM and PM, respectively. Root traits and dry matter and N accumulation in maize at the silking stage in FM were higher than those in FuM due to the synergistic root and mineral N spatial distribution in soil profiles. The PuM had higher post-anthesis dry matter and N accumulation than PM, which was attributed to the more root distribution in the un-mulched zone and deep soil (40–100 cm), higher leaf area index and chlorophyll relative content at the milk stage. Compared with FuM, FM cut down the ammonia volatilization loss by 17.6 % and prevented nitrate leaching. The PuM cut down the ammonia volatilization loss by 41.2 % compared with PM. Although there was no significant difference in the yield of FM-PuM, FM-PM and FuM-PuM, lower ammonia loss and smaller deep nitrate leaching in the rooting zone were observed under FM-PuM treatment. The band and deep applied N fertilizer under the film-mulched zone combined with planting in the un-mulched zone (FM-PuM) could be recommended as an effective agronomic practice for rainfed spring maize production with banded film mulching. • The N placement under film-mulched band cut down NH 3 loss and nitrate leaching. • Seeding at un-mulched zone increased post-anthesis dry matter and N accumulation. • The N and planting placement manipulated root and soil mineral N distribution. • Right N and planting placement enhanced maize yield and lowed N loss.

Effects of mixed fertilizers formed by the compounding of two targeted controlled-release nitrogen fertilizers on yield, nitrogen use efficiency, and ammonia volatilization in double-cropping rice

One-time application of mixed fertilizer formed by the compounding of two controlled-release nitrogen fertilizers (CRUs) with targeted N supply during the periods from transplantation (TS) to panicle initiation (PI) and from PI to heading (HS) is expected to synchronize the double-peak N demand of rice. However, its effects on the yield and N use efficiency (NUE) of labor-intensive double-cropping rice were unknown. Two targeted CRU (CRUA and CRUB) were compounded in five ratios (CRUA: CRUB = 10:0, 7:3, 5:5, 3:7, and 0:10) to form five mixed fertilizers (BBFs): BBF1–5. A field experiment was performed to investigate the characteristics of N supply in early and late seasons under different BBFs and their effects on N uptake, yield, and ammonia volatilization (AV) loss from paddy fields of double-cropping rice. Conventional high-yield fertilization (CK, three split applications of urea) and zero-N treatments were established as controls. The N supply dropped significantly with the increased compound ratio of CRUB during the period from TS to PI, but increased during the period from PI to HS. With the exception of the period from TS to PI in the late rice season, the N uptake of early and late rice maintained close synchronicity with the N supply of BBFs during the double-peak periods. Excessive N supply (BBF1 and BBF2) in the late rice season during the period from TS to PI increased N loss by AV. The effect of BBF on grain yield increase varied widely between seasons, irrespective of year. Among the BBFs, the BBF2 treatment of early rice not only stabilized the spikelets per panicle but also ensured a high number of effective panicles by promoting N uptake during the period from TS to PI and a high grain-filling percentage by appropriately reducing the N supply at the later PI stage, resulting in the highest rice yield. While stabilizing the effective panicle number, the BBF4 treatment of late rice increased the number of spikelets per panicle by promoting N uptake during the period from PI to HS, resulting in the highest rice yield. The two-year average yield and apparent N recovery efficiency of the BBF2 treatment during the early rice season were 9.6 t ha−1 and 45.3%, while those of late rice in BBF4 were 9.6 t ha−1 and 43.0%, respectively. The yield and NUE indexes of BBF2 in early rice and BBF4 in late rice showed no significant difference from those of CK. The AVs of BBF2 during the early rice season and of BBF4 during the late rice season were 50.0% and 76.8% lower, respectively, than those of CK. BBF2 and BBF4 could effectively replace conventional urea split fertilization in early and late rice seasons, ensuring rice yield and NUE and reducing AV loss in paddy fields.

Combing mechanical side-deep fertilization and controlled-release nitrogen fertilizer to increase nitrogen use efficiency by reducing ammonia volatilization in a double rice cropping system

Ammonia (NH3) volatilization losses result in low nitrogen use efficiency (NUE) and various environmental impacts in agroecosystems. Machine-transplanted rice with side-deep fertilization (MRSF) has been recommended as an effective alternative to traditional transplantation with manual broadcasting of fertilizer. Controlled-release nitrogen fertilizer (CRF) can enhance rice yield and NUE in paddy fields. However, there is scarce information about combined effects of MRSF and CRF on NH3 volatilization loss and rice grain yield, NUE, net economic benefit (NEB) in a double rice cropping system. In this study, a field experiment was conducted to evaluate the impact of MRSF with CRF on grain yields, NUE and economic returns of early rice and late rice from 2019 to 2021, as well as NH3 emissions in two rice seasons (2019 and 2021). Six treatments were designed as no N fertilizer (N0), compound fertilizer broadcasting (CFB), compound fertilizer side-deep placement (CFD), CRF broadcasting (CRFB), CRF side-deep placement (CRFD1), and single side-deep placement of CRF (CRFD2). The results showed that the CFD and CRFB treatments decreased NH3 volatilization while enhancing or maintaining rice yield and NUE compared to the CFB treatment. MRSF with CRF (CRFD1 and CRFD2) significantly reduced NH3 emissions of early and late rice by 57.6–67.9% and 62.2–80.9% by decreasing the NH4+–N concentrations in the surface water compared to the CFB treatment, respectively. Rice grain yields in the MRSF with CRF treatments increased by 3.9–17.3% in early rice and 5.4–21.6% in late rice relative to the CFB treatment. In addition, MRSF with CRF treatments improved NUE for early and late rice from 32.1 to 36.2% and 21.3–28.4% in the CFB treatment to 48.4–61.2% and 39.7–62.3%, respectively. The yield-scale NH3 volatilization losses were reduced under the MRSF with CRF treatments by 61.2–71.5% in early rice and 67.4–84.3% in late rice. Furthermore, MRSF with single basal application of CRF reduced time-consuming and labor-intensive while increasing rice yields and net economic benefits. Overall, co-application of MRSF and CRF can reduce NH3 emissions, and improve rice yield, NUE and profitability in double rice cropping systems.

Agro-environmental sustainability of using digestate fertilizer for solanaceous and leafy vegetables cultivation: Insights on fertilizer efficiency and risk assessment

Digestate generated from anaerobic digestion (AD) has been widely used as digestate fertilizer (DF) for plant growth, but its application should be comprehensively investigated. This study evaluates the effects of different amounts of DF on crop growth, nutrient use efficiency (NUE), soil properties, and potential negative impacts of DF application (salinity and heavy metals (HMs)) with two different crops (Eggplant and Shanghai cabbage). In eggplant cultivation, the yield increased with the increase of DF amount, and the yield of the DF-680 group was the highest (65.4 t/ha) under the highest fertilizer amount. However, due to high ammonia volatilization loss and excessive application, the NUE of DF was only about half of that of chemical fertilizer (CF). Significantly different from eggplant, the high application amount of DF resulted in yield reduction in Shanghai cabbage cultivation. The yield and NUE of the DF-170 group were the highest, the yield was 46.5 t/ha, and the NUE was more than twice compared to CF. Moreover, DF can raise soil nitrogen storage and alleviate soil acidification caused by fertilization in both batches of cultivation. Nevertheless, the electrical conductivity (EC) value of the soil was increased by 2–3 times, and the long-term application may lead to soil salinization. On the other hand, the increase of DF application elevated the content of copper (Cu), zinc (Zn), and cadmium (Cd) in soil significantly but did not cause HMs contamination in crops and tillage soil. In summary, reasonable application amounts and methods should be considered when applying DF.

Negligible ammonia volatilization loss with one-time root-zone targeted application of common nitrogen, phosphorus, and potassium fertilizers in transplanted rice cultivation

The minimization of nitrogen (N) loss and enhancement of efficient N use are of great importance in agricultural crop production. Here we propose a method of one-time root-zone targeted fertilization (ORZTF), to reduce ammonia volatilization (AV) loss and increase N use efficiency. ORZTF is updated from one-time root-zone fertilization (ORZF), in which common N fertilizer is one-time applied in crop root-zone, and phosphate (P) and potassium (K) are surface broadcasted. In ORZTF, common N, P and K are together placed at certain sites in the root-zone. Three rice field trials with the methods of conventional surface broadcasting (CSB), ORZF, and ORZTF, and a soil incubation experiment with CSB and ORZTF, were conducted. In 2018, the treatments comprised CSB with no N (N0), with the local N rate (CSB, 195 kg N hm−2 and 150 kg N hm−2 for two sites, respectively), with higher N (HCSB, 225 kg N hm−2 and 195 kg N hm−2, respectively), ORZF (195 kg N hm−2 and 150 kg N hm−2, respectively), and ORZTF (195 kg N hm−2 and 150 kg N hm−2, respectively). In 2019, the treatments were: N0, CSB, ORZF, ORZTF with urea (ORZTF-U), with ammonium chloride (ORZTF-Cl), and with ammonium sulfate (ORZTF-S) at 180 kg N hm−2. In the incubation experiment, there’re three treatments: N0, CSB, and ORZTF. The rates of P and K were the same in all experiments. Compared with CSB, ORZTF and ORZF significantly increased the yield, N uptake, N recovery efficiency, and N partial factor productivity of rice with the same N input. After 4.5 months of incubation, 78.5–92.7% of fertilizer N was reserved in the soils with ORZTF, about two-fold that with CSB. In all field and incubation experiments, AV loss was negligible when N was one-time root-zone applied alone or together with PK, close to that in N0 treatment. Compared with ORZF, ORZTF seemed to be a more promising method in rice fertilization, having the similar effect on N uptake increase and N loss reduction, but more convenience. Although the benefits of targeting fertilization were not significantly observed in the current work, with the idea of ‘fertilizing the roots but not the soil’, the method of ORZTF with common N, P and K fertilizers should be beneficial for cleaner and more efficient agricultural crop production in China.

Unexpected high suppression of ammonia volatilization loss by plastic film mulching in Korean maize cropping system

Plastic film mulching (PFM) as an agronomic practice was rapidly expanded to improve crop yield and quality, mainly due to improving soil water and temperature condition. PFM has been known to increase greenhouse gas (GHG) emissions, but its influence on ammonia (NH3) volatilization loss was not properly studied. To determine the impact of PFM on NH3 emission loss, PFM and no-mulching were designed as the main treatment. In addition, chemical (NPK) and organic fertilization plots as the sub-treatment were placed under the same mulching condition. In the NPK, the recommendation level (N-P2O5-K2O=186–35–74 kg ha-1) of chemical fertilizers was only applied for maize cultivation. In the organic fertilization, the mixture of barley and hairy vetch was cultivated during the fallow season and its whole biomass as green manure was incorporated for maize cultivation. PFM considerably improved average soil water and temperature regimes during cropping season by 0.02–0.05 m3 m-3 and 0.8–1.4 ℃ over no-mulching, respectively. These improved soil properties enhanced maize grain yield by around 95–270 and 80–300% in NPK and organic fertilization plots over no-mulching, respectively. The emission loss of NH3 gas which is highly water-soluble was 70–215% higher in NPK than organic fertilization under the same mulching. However, PFM significantly decreased seasonal NH3 emission loss by approximately 40–45% over no-mulching, probably due to physical trapping in water drops under the plastic film. To verify the suppression mechanism of NH3 emission loss by PFM, the emission rates of nitrous oxide (N2O) which is a water-insoluble gas were simultaneously monitored using the closed chamber method. Different from NH3 emission loss, PFM slightly increased N2O emission without a statistical difference, regardless of fertilization background. In conclusion, PFM could be a very useful cropping practice to decrease NH3 emission loss, as well as improve soil properties and crop productivity.

Distinct enhanced efficiency urea fertilizers differentially influence ammonia volatilization losses and maize yield

Distinct enhanced efficiency urea fertilizers differentially influence ammonia volatilization losses and maize yield

Analysis of Ammonia Volatilization Loss from a Paddy Soil with Empirical and Mechanistic Models

AbstractAmmonia volatilization from agricultural land has a negative impact on the atmospheric, aqueous, and land environments. However, this process is still not fully understood. In this study, a 2‐year field experiment is conducted in the Taihu Lake region of China to monitor ammonia volatilization from a paddy soil. The ammonia volatilization losses are in the range of 43.4 to 53.6 kg N ha−1 in the year 2013 and 25.9 to 35.4 kg N ha−1 in the year 2014, which account for 19.7% to 19.9% and 11.8% to 13.1% of the applied nitrogen with two different N treatments (N1: 220 kg N ha−1, N2: 270 kg N ha−1). The ammonia volatilization loss is highest during the basal fertilizer application, followed by the tillering and the ear‐differentiation stages. Then, two empirical models and one mechanistic model are used to simulate the ammonia volatilization process. These models are calibrated and validated with field experimental data. The results show that none of the three models accurately predict the ammonia volatilized from the rice field (R2 < 0.40), however, among the three models evaluated, the mechanistic model is more effective in simulating the ammonia volatilization process (R2 = 0.38).

Duromide increase NBPT efficiency in reducing ammonia volatilization loss from urea

ABSTRACT Novel fertilizer stabilization technologies are needed to decrease ammonia (NH3-N) losses and increase nitrogen use efficiency. Duromide + NBPT is a new technology that combines two molecules, Duromide and NBPT, whose propose is to increase the efficiency of the urease inhibitor NBPT in reducing NH3-N loss from urea. Preliminary results showed that Duromide + NBPT can be a more effective product than just NBPT, particularly under low soil pH and high-temperature conditions. This study aimed to compare the effects [...]

No significant influence of biochar and manure application on nitrogen fate and sequestration by tomato and garlic crops: A field experiment in California, USA

AbstractOrganic soil amendments can improve soil health but their role in improving N management has not been well quantified. The objectives of this research were to evaluate the influence of biochar and manure compost application on crop yield, N uptake, changes in soil and environmental losses and to use the information to assess the N requirement and project fertilization needs. A field experiment was conducted in California, USA, with processing tomato (Lycopersicon esculentum Mill.) grown first, followed by garlic (Allium sativum). The soil was a sandy loam with a pH of 7.2 and CEC of 9.1 cmol(+) kg−1. Treatments included two biochar products, derived from almond shell or softwood feedstocks, applied at 20 or 40 tonnes (t) ha−1, dairy manure compost at 20 t ha−1, combinations of the manure and the biochar (each at 20 t ha−1), and a control. Although biochar and manure applications improved the surface soil organic C and total N content, no significant effects on crop yield, biomass and N uptake, as well as ammonia volatilization and leaching loss, were observed. The amount of N sequestered by plants ranged from 3.2 to 3.8 and 9.9 to 10.0 kg N Mg−1 to produce fresh tomato fruits and garlic bulbs, respectively. However, about half of the N for tomato and 93% for garlic plants were removed from soil by harvesting. The N sequestered per unit biomass (or yield) production appears a stable parameter, which can be used to reliably project fertilization needs that target high NUE and minimal loss to the environment.

Influence of Nano-Zinc Oxide Coated Urea Fertilizer on Ammonia Volatilization Loss and Inorganic Nitrogen Content in Loamy Sand Soil

A laboratory incubation experiment in a closed dynamic air flow system was conducted for 30 days to estimate the volatilization loss of NH3-N from 0, 1, 2 and 3% Nano-ZnO coated urea treated soil. The volatilized NH3-N from the soil chambers was collected and titrated every 48 hours. Another incubation experiment was carried out to study the effect of coating urea with Nano-ZnO on the inorganic nitrogen (NH4-N and NO3-N) content in the treated soils at 2, 4, 8, 14 and 21 days of incubation period. The two experiments were arranged in a completely randomized design with three replications. The results of the first experiment indicated that coating urea fertilizer with Nano-ZnO reduced the total loss of NH3-N from 22.82 % of applied N in the soil treated with uncoated urea (0 % coating) to 13.03% for the highest coating level (3%) with a reduction in NH3-N loss by 42.90%.The results of second incubation experiment showed that the average of NH4-N content increased from 86.52 mg Kg-1 for 0% Nano-Zn coated urea to 131.04 mg Kg-1 in the soil treated with 3% Nano-Zn coated urea, and the ratio of extractable NO3-N average to the extractable NH4-N average was 1: 1.06, 1: 1.17, 1: 1.50 and 1: 1.75 in the soil treated with 0, 1, 2 and 3% Nano-Zn coated urea, respectively. Also, the average of total inorganic N content increased from 168.19 mg Kg-1 in the soil treated with uncoated urea (0% coating) to 205.70 mg Kg-1 in soil treated with highest coating level (3%).Therefore, using the Nano-Zn coated urea fertilizer improves nitrogen use efficiency and reduce ammonia loss from urea fertilizer applied to loamy sand soil.