Ammonia Volatilization from Winter Wheat Field Top Dressed with Urea

Ammonia volatilization was measured with a continuous air flow enclosure method from a winter wheat field in the Experimental Farm of Jurong Agricultural School to investigate its main influencing factors. The experiment with five treatments in triplicate, no N (control), 100, 200 and 300 kg N ha-1 with rice straw cover at a rate of 1500 kg ha-1 and 200 kg N ha-1 without rice straw, started when the winter wheat was sown in 1994. Sixty percent of the total amount of N applied was hasal and 40% was top-dressed. The measurement of ammonia volatilization was immediately conducted after urea was top-dressed on soil surface at wheat elongation stage in spring of 1996 and 1997. The results showed that there was a diurnal variation of ammonia volatilization rate from the winter wheat field, which synchronized with air temperature. N losses through ammonia volatilization increased with increasing N application rate, but the ratio of N lost through ammonia volatilization to applied N was not significantly affected by N application rate. The coverage of rice straw had no significant effect on ammonia volatilization. Soil moisture and rain events after urea was top-dressed affected ammonia volatilization significantly.

Ammonia Volatilization and Nitrogen Utilization Efficiency in Response to Urea Application in Rice Fields of the Taihu Lake Region,China

Ammonia volatilization losses, nitrogen utilization efficiency, and rice yields in response to urea application to a rice field were investigated in Wangzhuang Town, Changshu City, Jiangsu Province, China. The N fertilizer treatments, applied in triplicate, were 0 （control）, 100, 200, 300, or 350 kg N ha^-1. After urea was applied to the surface water, a continuous airflow enclosure method was used to measure ammonia volatilization in the paddy field. Total N losses through ammonia volatilization generally increased with the N application rate, and the two higher N application rates （300 and 350 kg N ha^-1） showed a higher ratio of N lost through ammonia volatilization to applied N. Total ammonia loss by ammonia volatilization during the entire rice growth stage ranged from 9.0% to 16.7% of the applied N. Increasing the application rate generally decreased the ratio of N in the seed to N in the plant. For all N treatments, the nitrogen fertilizer utilization efficiency ranged from 30.9% to 45.9%. Surplus N with the highest N rate resulted in lodging of rice plants, a decreased rate of nitrogen fertilizer utilization, and reduced rice yields. Calculated from this experiment, the most economical N fertilizer application rate was 227 kg ha^-1 for the type of paddy soil in the Taihu Lake region. However, recommending an appropriate N fertilizer application rate such that the plant growth is enhanced and ammonia loss is reduced could improve the N utilization efficiency of rice.

Ammonia Volatilization Losses from Urea Applied to Wheat on a Paddy Soil in Taihu Region, China

Ammonia volatilization losses from urea applied as a basal fertilizer and a top dressing at tillering stage in a wheat field of Taihu Region, China, were measured with a micrometeorological technique. Urea as fertilizer was surface broadcast at 81 (low N) and 135 (high N) kg N ha-1 as basal at the 3-leaf stage of the wheat seedling on December 2002, and 54 (low N) and 90 (high N) kg N ha-1 as top dressing on February 2003. Ammonia volatilization losses occurred mainly in the first week after applying N fert…

Ammonia Volatilization and Deriitrification Losses from an Irrigated Maize-Wheat Rotation Field in the North China Plain

Ammonia (NH3) volatilization, denitrification loss, and nitrous oxide (N2O) emission were investigated from an irrigated wheat-maize rotation field on the North China Plain, and the magnitude of gaseous N loss from denitrification and NH3 volatilization was assessed. The micrometeorological gradient diffusion method in conjunction with a Bowen Ratio system was utilized to measure actual NH3 fluxes over a large area, while the acetylene inhibition technique (intact soil cores) was employed for measurement of denitrification losses and N2O emissions. Ammonia volatilization loss was 26.62% of the applied fertilizer nitrogen (N) under maize, while 0.90% and 15.55% were lost from the wheat field at sowing and topdressing, respectively. The differences in NH3 volatilization between different measurement events may be due to differences between the fertilization methods, and to differences in climatic conditions such as soil temperature.Denitrification losses in the fertilized plots were 0.67%-2.87% and 0.31%-0.49% of the applied fertilizer N under maize and wheat after subtracting those of the controls, respectively. Nitrous oxide emissions in the fertilized plots were approximately 0.08%-0.41% and 0.26%-0.34% of the applied fertilizer N over the maize and wheat seasons after subtracting those of the controls, correspondingly. The fertilizer N losses due to NH3 volatilization were markedly higher than those through denitrification and nitrous oxide emissions. These results indicated that NH3 volatilization was an important N transformation in the crop-soil system and was likely to be the major cause of low efficiencies with N fertilizer in the study area. Denitrification was not a very important pathway of N fertilizer loss, but did result in important evolution of the greenhouse gas N2O and the effect of N2O emitted from agricultural fields on environment should not be overlooked.

Ammonia Volatilization from Urea Applied to Acid Paddy Soil in Southern China and Its Control

Results showed that ammonia loss from urea broadcast into floodwater and incorporated into soil at transplanting was as high as 40% of applied N,and the corresponding total nitrogen (N) loss was 56%.Ammonia loss was measured with simplified micrometeorological method (ammonia sampler),and total N loss was concurrently measured using ^15N balance technique.The experiment was conducted under strong sunshine conditions on acid paddy soil derived from Quaternary red clay.The ammonia loss in this particular condition was much greater than those obtained from previous studies when urea was also applied to acid paddy soil but under cloudy conditions.It is concluded that the strong sunshine conditions with high temperature and shallow floodwater during the period of present experiment favoured ammonia volatilization.Application of stearyl alcohol on the surface of the floodwater reduced ammonia loss to 23% of applied N.However,the effect of stearyl alcohol was short-lived,probably due to the microbiological decomposition.

Effects of Nitrogen Application Level on Rice Nutrient Uptake and Ammonia Volatilization

The effects of different nitrogen application levels on nutrient uptake and ammonia volatilization were studied with the rice cultivar Zheyou 12 as a material.The accumulative amounts of nitrogen,phosphorus and potassium in rice plants across all growth stages showed a trend to increase with increasing nitrogen application levels from 0 to 270 kg/hm 2,but decreased at nitrogen application levels exceeding 270 kg/hm 2.Moreover,the accumulative uptake of nitrogen,phosphorus and potassium by the rice plants was increased by application of organic manure in combination with 150 kg/hm 2 nitrogen.The nitrogen uptake was high during the jointing to heading stages.Correlation analysis showed that rice yield was positively correlated with the accumulative uptake of nitrogen,phosphorus and potassium by the rice plants.The highest correlation coefficient observed was between the amount of nitrogen uptake and rice yield.The rate and accumulative amounts of ammonia volatilization increased with increasing nitrogen fertilizer application level.Compared with other stages,the rate and accumulative amount of ammonia volatilization were higher after base fertilizer application.The ammonia volatilization rates in response to the nitrogen application levels of 270 kg/hm 2 and 330 kg/hm 2 were much higher than those in the other treatments.The loss of nitrogen through ammonia volatilization accounted for 23.9% of the total applied nitrogen at the nitrogen application level of 330 kg/hm 2.

Ammonia volatilization losses and ^(15)N balance from urea applied to rice on a paddy soil

Ammonia volatilization loss and ^15N balance were studied in a rice field at three different stages after urea application in Taihu Lake area with a micrometeorological technique. Factors such as climate and the NH4^＋-N concentration in the field floodwater affecting ammonia loss were also investigated. Results show that the ammonia loss by volatilization accounted for 18.6%-38.7% of urea applied at different stages, the greatest loss took place when urea was applied at the tillering stage, the smallest at the ear bearing stage, and the intermediate loss at the basal stage. The greatest loss took place within 7 d following the fertilizer application. Ammonia volatilization losses at three fertilization stages were significantly correlated with the ammonium concentration in the field floodwater after the fertilizer was applied. ^15N balance experiment indicated that the use efficiency of urea by rice plants ranged between 24.4% and 28.1%. At the early stage of rice growth, the fertilizer nitrogen use efficiency was rather low, only about 12%. The total amount of nitrogen lost from different fertilization stages in the rice field was 44.1%-54.4%, and the ammonia volatilization loss was 25.4%-33.3%. Reducing ammonia loss is an important treatment for improving N use efficiency.

Effects of Nitrogen Application Levels on Ammonia Volatilization and Nitrogen Utilization during Rice Growing Season

We conducted field trials of rice grown in sandy soil and clay soil to determine the effects of nitrogen application levels on the concentration of NH4＋-N in surface water, loss of ammonia through volatilization from paddy fields, rice production, nitrogen-use efficiency, and nitrogen content in the soil profile. The concentration of NH4＋-N in surface water and the amount of ammonia lost through volatilization increased with increasing nitrogen application level, and peaked at 1-3 d after nitrogen application. Less ammonia was lost via volatilization from clay soil than from sandy soil. The amounts of ammonia lost via volatilization after nitrogen application differed depending on the stage when it was applied, from the highest loss to the lowest： N application to promote tillering 〉 the first N topdressing to promote panicle initiation （applied at the last 4-leaf stage） 〉 basal fertilizer 〉 the second N topdressing to promote panicle initiation （applied at the last 2-leaf stage）. The total loss of ammonia via volatilization from clay soil was 10.49-87.06 kg/hm2, equivalent to 10.92%-21.76% of the nitrogen applied. The total loss of ammonia via volatilization from sandy soil was 11.32-102.43 kg/hm2, equivalent to 11.32%-25.61 % of the nitrogen applied. The amount of ammonia lost via volatilization and the concentration of NH4＋-N in surface water peaked simultaneously after nitrogen application; both showed maxima at the tillering stage with the ratio between them ranging from 23.76% to 33.65%. With the increase in nitrogen application level, rice production and nitrogen accumulation in plants increased, but nitrogen-use efficiency decreased. Rice production and nitrogen accumulation in plants were slightly higher in clay soil than in sandy soil. In the soil, the nitrogen content was the lowest at a depth of 40-50 cm. In any specific soil layer, the soil nitrogen content increased with increasing nitrogen application level, and the soil nitrogen content was higher in clay soil than in sandy soil. In terms of ammonia volatilization, the amount of ammonia lost via volatilization increased markedly when the nitrogen application level exceeded 250 kg/hm2 in the rice growing season. However, for rice production, a suitable nitrogen application level is approximately 300 kg/hm2. Therefore, taking the needs for high crop yields and environmental protection into account, the appropriate nitrogen application level was 250-300 kg/hm2 in these conditions.

Evaluation of Methods for Control of Ammonia Volatilization from Surface-Applied Nitrogen Fertilizers to Sugarcane Trash in North Queensland

Micrometeorological and microplot experiments were conducted in the field of freshly harvested green cane in Queensland, Australia. Results showed that high ammonia loss of fertilizer N could occur under relatively dry conditions when urea or commercial product of mixture of urea and muriate of potash were applied to the surface of sugarcane trash. The moisture content in the trash and the pH of fertilizer were two important factors controlling the processes of urea hydrolysis and ammonia volatilization. Most of the N in the soil was transformed to the nitrate+ nitrite from after 70 days of fertilizer application. No significant leaching was found. Urea-free N fertilizers had higher N recoveries compared to urea-containing fertilizers. .

Effects of different long-term crop straw management practices on ammonia volatilization from subtropical calcareous agricultural soil

Ammonia(NH3)volatilized from agricultural production and its secondary aerosols contribute greatly to air pollution.Different long-term crop straw management practices may significantly affect the soil fertility and soil nitrogen cycle,however,the effect on NH3 volatilization has not been well studied.Therefore,a one-year field experiment was conducted to evaluate the effect of straw incorporation on NH3 volatilization from subtropical calcareous agricultural soil from a longterm perspective,including four treatments:synthetic fertilizer(CK);synthetic fertilizer incorporation with 100%or 50%of the previous season’s crop straw(SI1 and SI2,respectively);and synthetic fertilizer incorporation with 50%burned crop straw(SI2B).Soil NH3 volatilizations were monitored through a wheat–maize rotation year by using a dynamic chamber method.The results demonstrated that NH3 volatilization primarily occurred within 38 days and 7–10 days following nitrogen fertilization events for the wheat and maize seasons,respectively.Different crop straw management practices mainly impacted the NH3 flux of the basal fertilization rather than the topdressing fertilization;long-term crop straw incorporation effectively lowered NH3 loss(35.1%for SI1 and 16.1%for SI2 compared to CK;and the inhibiting effect increased with increasing straw amount,possibly contributed by the high straw carbon/nitrogen ratio,and enhanced microbial activity,which contributed to inorganic nitrogen immobilization and lower ammonium content in the topsoil.However,SI2B significantly increased(29.9%)the annual NH3 flux compared with SI2,indicating that long-term 100%straw incorporation could be a promising straw management practice for mitigating NH3 loss and increasing soil fertility.

Dry deposition of ammonia around paddy fields in the subtropical hilly area in southern China

This study measured the ammonia(NH3)concentration and dry deposition within 100 m around paddy fields(0.6 ha)with double rice cropping in the subtropical hilly area in southern China,with the aims to quantify the dry deposition of NH3 around the emission source and to clarify its temporal and spatial variability.The results showed that high NH3 concentrations were found during the 15 d after nitrogen(N)fertilizer application at downwind sites within 100maround the paddy fields,and the NH3 concentrations were 12–62,2.8–7.3,13–38,and 4.9–36μg N m−3 during the 15 d after basal fertilizer application and topdressing in the early rice season and after basal fertilizer application and topdressing in the late rice season,respectively.The NH3 concentrations were relatively low(1.5–-3.8μg N m−3)during other periods of the rice season at the downwind sites,which indicated that N fertilizer application in paddy fields highly affected the NH3 concentration at downwind sites.The NH3 concentrations at the downwind sites decreased significantly with the increase in distance from the paddy fields.The total NH3 dry deposition around 100 m of the paddy fields accounted for approximately 79%and 81%of the emitted NH3 from the paddy fields in the early and late rice seasons,respectively.The results indicate that dry deposition of NH3 around emission sources may be an important way to remove the NH3 volatilized from croplands in this subtropical hilly area.

Nitrogen mobility,ammonia volatilization,and estimated leaching loss from long-term manure incorporation in red soil

Nitrogen（N） loss from fertilization in agricultural fields has an unavoidable negative impact on the environment and a better understanding of the major pathways can assist in developing the best management practices. The aim of this study was to evaluate the fate of N fertilizers applied to acidic red soil（Ferralic Cambisol） after 19 years of mineral（synthetic） and manure fertilizer treatments under a cropping system with wheat-maize rotations. Five field treatments were examined： control（CK）, chemical nitrogen and potash fertilizer（NK）, chemical nitrogen and phosphorus fertilizer（NP）, chemical nitrogen, phosphorus and potash fertilizer（NPK） and the NPK with manure（NPKM, 70% N from manure）. Based on the soil total N storage change in 0–100 cm depth, ammonia（NH_3） volatilization, nitrous oxide（N_2O） emission, N plant uptake, and the potential N leaching loss were estimated using a mass balance approach. In contrast to the NPKM, all mineral fertilizer treatments（NK, NP and NPK） showed increased nitrate（NO_3~–） concentration with increasing soil depth, indicating higher leaching potential. However, total NH_3 volatilization loss was much higher in the NPKM（19.7%） than other mineral fertilizer treatments（≤4.2%）. The N_2O emissions were generally low（0.2–0.9%, the highest from the NPKM）. Total gaseous loss accounted for 1.7, 3.3, 5.1, and 21.9% for NK, NP, NPK, and NPKM treatments, respectively. Estimated N leaching loss from the NPKM was only about 5% of the losses from mineral fertilizer treatments. All data demonstrated that manure incorporation improved soil productivity, increased yield, and reduced potential leaching, but with significantly higher NH_3 volatilization, which could be reduced by improving the application method. This study confirms that manure incorporationis an essential strategy in N fertilization management in upland red soil cropping system.

Ammonia Volatilization from Soils Fertilized with Different Nitrogen Type and Application Method in Germination and Early Seedling Stages from the Radish Field

Ammonia volatilization(AV) from basal fertilizer with different nitrogen(N) types and application methods was investigated by the ventilation method in germination and early seedling stages during radish growth seasons in 2014. Four N fertilizer types, urea(U), ammonium bicarbonate(AB), ammonia sulfate(AS), and controlled urea formaldehyde(CUF) were applied through 5 cm depth placement(I) and 10 cm depth placement(II). The results showed that the N fertilizer type was the main factor that caused AV loss in germination and early seedling stages from the radish field. The highest and the lowest cumulative AV losses in germination and early seedling stages from the radish fields were 33.23 and 11.21 N kg/hm^2 for the treatments of AB+I and CUF+II, respectively, accounting for 60.40 and 26.40% of the N application for each treatment. The 10 cm deep placement of N reduced AV rates and lagged the AV process, and CUF significantly reduced ammonia volatilization. The data showed that the suitable N fertilizer type and application method for basal fertilizer were CUF and deep placement, respectively.Therefore, fertilizing with proper N fertilizer types and methods should be the efficient measures to mitigate AV losses from the radish field and will alleviate environment problems.

Model Research on the Effect of Surface Film on Ammonia Volatilization from Rice Field

Pan and field experiments were conducted to investigate the effect of surface film on ammonia volatilization from water and paddy soil. The results showed that the addition of the surface film on floodwater reduced the rate of ammonia volatilization, however, the reduction of the latter varied greatly with its rates of addition. Jayaweera-Mikkelsen ammonia volatilization model with the introduction of a parameter Kf, a relative measure of the resistance of the surface film on ammonia volatilization, was used to elucidate the effectiveness of the surface film on lowering ammonia volatilization. The Kf value was calculated from the results ob-

A Comparative Study of Nitrogen Loss after Application of Biochar Coated Urea and Common Urea in Vegetable Soil at Chaihe Catchment of Dianchi Lake

[Objective] This study aimed to provide the basis for scientific and rea- sonable application of nitrogen fertilizer and control Of agricultural non-point source pollution in vegetable-growing area at Chaihe catchment of Dianchi Lake. [Method] A pot experiment was carried out to compare the loss of nitrogen via ammonia volatilization and nitrogen leaching after application of biochar coated urea （BCU） and common urea （Urea） with different nitrogen rates （0 mg N/kg soil, 400 mg N/kg soil, 320 mg N/kg soil and 280 mg N/kg soil）. [Result] The results indicated that the amount of nitrogen loss was proportional to nitrogen applied rate. Leaching nitrogen was higher than ammonia volatilization. Compare with Urea treatments, ammonia volatilization and nitrogen leaching losses were significantly lower in BCU treatments at the same nitrogen application rate. At the nitrogen application rate of 320 and 280 mg N/kg soil, nitrogen loss, ammonia volatilization and leaching nitrogen was 43.5%-45.5%, 3.7%-21.7% and 49.8%-52.1% lower in BCU treatments than in Ure- a treatments, respectively. [Conclusion] The application of BCU could minimize nitro- gen loss by reducing nitrate leaching loss. It can be concluded that the low nitrogen application rate combined with BCU have a practical influence on controlling the risk of nitrogen pollution in Dianchi Lake.

Study on the Nitrogen Release Law of Bamboo Charcoal-coated Urea and Its Biological Utilization Effects

[Objective] The study about the nitrogen releasing law of bamboo-charcoal coated urea and the biologic utilization effect was to find the coated urea with high efficiency,low price and simple production technology.[Method]Two kinds of bamboo-charcoal coated urea(BCCU)with different coating thickness were made by using bamboo-charcoal and macromolecule polymer as coating material.The experiments of soil eluviate,ammonia volatilization in corn field and potted plant of corn were conducted to study the nitrogen releasing law and the biologic utilization effect of self-made BCCU.[Result]The BCCU showed some slow-release capability and their accumulated nitrogen releasing rates in 29 d were 9.93%-16.27% lower than that of normal urea.Compared with the normal urea,the volatilization rate of ammonia in BCCU reduced to 16.66%-31.8%,the biomass of corn and nitrogen utilization rate increased by 12.8%-24.1% and 10.5%-16.99%,respectively.[Conclusion]Bamboo-charcoal in coated urea not only had some slow-release capability,but also had some adsorbability,which would reduce the eluviation and volatilization of nitrogen and protect environment from N pollution.

Nitrogen Cycling and Losses Under Rice-Wheat Rotations with Coated Urea and Urea in the Taihu Lake Region

A lysimeter experiment with undisturbed soil profiles was carried out to study nitrogen cycling and losses in a paddy soll with applications of coated urea and urea under a rice-wheat rotation system in the Taihu Lake region from 2001 to 2003. Treatments for rice and wheat included urea at conventional, 300 （rice） and 250 （wheat） kg N ha^-1, and reduced levels, 150 （rice） and 125 （wheat） kg N ha^-1, coated urea at two levels, 100 （rice） and 75 （wheat） kg N ha^-1, and 150 （rice） and 125 （wheat） kg N ha^-1, and a control with no nitrogen arranged in a completely randomized design. The results under two rice-wheat rotations showed that N losses through both NH3 volatilization and runoff in the coated urea treatments were much lower than those in the urea treatments. In the urea treatments N runoff losses were significantly （P 〈 0.001） positively correlated （r = 0.851） with applied N. N concentration in surface water increased rapidly to maximum two days after urea application and then decreased quickly. However, if there was no heavy rain within five days of fertilizer application, the likelihood of N loss by runoff was not high. As the treatments showed little difference in N loss via percolation, nitrate N in the groundwater of the paddy fields was not directly related to N leaching. The total yield of the two rice-wheat rotations in the treatment of coated urea at 50% conventional level was higher than that in the treatment of urea at the conventional level. Thus, coated urea was more favorable to rice production and environmental protection than urea.

Gaseous Loss of Nitrogen from Fertilizers Applied to Wheat on a Calcareous Soil in North China Plain

Nitrogen (N) losses from ammonium bicarbonate or urea applied to wheat and then followed immediately by irrigation were investigated. Ammonia volatilization was determined by a micrometeorological method (ammonia sampler), total N loss was estimated by the 15N mass balance method, and denitrification loss was measured by the difference method (calculated from the difference between the total N loss and ammonia loss)and a direct method (measuring the emission of (N2+N2O)-15N ). Total ammonia losses from ammonium bicarbonate and urea in 33 days were 8.7% and 0.9% of the applied nitrogen, respectively. The corresponding total N losses were 21.6% and 29.5%. Apparent denitrification losses (by the difference method) were rather high, being 12.9% from ammonium bicarbonate and 28.6% from urea. However, no emission of (N2+N2O)-15N was detected using the direct method.

Gaseous Loss of Nitrogen from Fertilizers Applied to a Paddy Soil in Southeastern China

Total nitrogen (N) loss and ammonia volatilization from urea applied to flooded rice grown on a paddy soil in Zhejiang Province were measured by 15N balance and micro-meteorological methods, respectively. Floodwater properties and ammonia loss from the circular plot were compared with those from the microplots. And the effectiveness of urease inhibitor, NBPT [N-(n-butyl) thiophosphonc triamide], was also tested Results showed that the total losses from urea broadcast and incorporated at transplanting (basal dressing) were similar with those from urea broadcast 12 days after transplanting (top-dressing) (51.5% and 48%, respectively, of applied N), and ammonia losses were low, the corresponding figures were 10.8% and 7.0% of applied N, respectively. Thus, denitrification was a much more important pathway of nitrogen loss than ammonia volatilization under the particular conditions. Addition of NBPT retarded urea hydrolysis, reduced pHs and ammoniacal nitrogen concentrations of floodwater for either the application of urea as basal or as top-dressing, but these effects were not translated into the reduction of total nitrogen loss. Floodwater pHs and ammonia loss in the microplots were apparently lower than those in the circular plot from urea applied as basal dressing; however, such differences were not found when urea was top-dressed. The frequently raining days occurred after top-dressing may be responsible for the insignificant effect of plot size on floodwater pHs and ammonia volatilization. It seems that the effects of plot size on floodwater properties and ammonia loss mainly depend on weather conditions, in addition to the height and leaf area index of the crop.

Evaluation of Pathway of Nitrogen Loss in Winter Wheat and Summer Maize Rotation System

The nitrogen loss pathway in winter wheat and summer maize rotation system was studied based on field experimental data. The results showed that nitrogen recovery rate was significantly decreased with nitrogen fertilization rate increased, while residual rate and losses rate had an increasing trend. Accumulated ammonia volatilization loss in winter wheat and summer maize rotation was 12. 8(N0), 22.0(N120), 33. 0(N240) and 64. 5 kg N ha-1 (N360) respectively and rate of ammonia volatilization loss was 3.8, 4.2 and 7.2% respectively while urea was mixed with 0 -10 cm soil or spread before irrigation. Denitrification loss with acetylene-soil core incubation method in winter wheat was lower than 1 kg N ha-1 and rate of denitrification loss was 0. 21 - 0. 26% or trace. Denitrification loss in summer maize was 1 - 14 kg N ha-1 and rate of denitrification loss was 1-5%. The total gaseous loss in winter wheat and summer maize rotation system was less than 10%, and the main nitrogen fertilizer loss way was leaching below 0 - 100 cm soil profile and accumulated in deeper soil.