Ammonia volatilization from poultry manure-amended soil

Summary Poultry manure (PM) is commonly applied to cropland as a fertilizer, usually at rates determined by the nitrogen content of the manure. Limited information is available, however, on the volatilization of ammonia from poultry manure-amended soils, despite the effect these losses may have on the fertilizer value of the manure. This study was initiated to determine the influence of incorporation and residue cover on NH₃ losses from PM-amended soils. In the first experiment, a dynamic flow technique was used to measure NH₃ losses from 18 manures applied to a bare soil surface at a rate of 12 Mg ha^-1. In the second experiment, 3 of the 18 manures were incorporated either immediately, 24 h or 72 h after application. The third experiment compared the same three manures applied to a bare soil surface or to corn or soybean residues. Surface application of the manures resulted in the loss of from 4 to 31% of the total N applied in the manures. Incorporation of the PM with soil significantly reduced NH₃ loss with the greatest decrease following immediate incorporation. Crop residues either had no effect or slightly reduced NH₃ volatilization losses relative to PM application to a bare soil surface. Ammonia volatilization was not well correlated with individual manure properties, but a multiple regression approach using manure pH and total N content offered some promise as a means to segregate manures of the basis of volatilization potential.     

Ammonia volatilization from ammonium sulfate as sulfur source

Surface application of ammonium sulfate (AMS) as S source to soils with pH ≥7.0 is subjected to ammonia (NH₃) volatilization. However, AMS volatilizes less NH₃ than urea does. In soils with pH <7.0, unlike urea, very little NH₃ volatilization from AMS occurs. The associated N with AMS may enhance early biological N fixation by leguminous crops as compared to S sources without N such as polyhalite.     

Ammonia volatilization from nitrogen fertilizers with and without gypsum

Abstract. Ammonia volatilization with and without gypsum incorporation was measured in Gujranwala soil (Udic Haplustalf) in an incubation study using different nitrogen fertilizers e.g. urea, ammonium sulphate (AS), calcium ammonium nitrate (CAN), and urea nitrophos (UNP). Nitrogen from different fertilizers was applied at the rate of 200 mg N kg⁻¹ to two sets of soils in plastic bags (1.0 kg soil) and plastic jars (0.5 kg soil). Soil moisture was maintained at field capacity. Application of urea increased soil pH to 9, three hours after its addition. Ammonium sulphate and calcium ammonium nitrate had little effect on soil pH. Ammonium volatilization losses from fertilizers were related to the increase in soil pH caused by the fertilizers. Consequently maximum losses were recorded due to application of urea. Losses through ammonia volatilization were significantly lower with AS, CAN and UNP in descending order. Gypsum incorporation significantly reduced the losses. Therefore, application of gypsum to soil before urea may substantially improve N use efficiency for crop production by reducing N losses.     

表施尿素的冬小麦土壤氨挥发损失

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 1 500 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 basal 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.     

华北太行山前平原农田氨挥发损失

我国氮肥用量约占全世界氮肥总用量的三分之一[1],但当季利用率仅为30%～35%左右[2].据报道,石灰性土壤中氨挥发是氮素损失的主要途径之一[3-4],其损失量相当于氮素总损失量的20%～71%[2,5-7 ].进入大气中的氨引起自然土壤和水体的氮素含量升高,产生富营养化[8],导致植物种类更替和部分物种灭绝[9].     

尿素二次加工产品的氨挥发损失特征研究

应用密闭法对尿素及其二次加工产品—复合肥料、包膜尿素和包膜复合肥料在施入土壤后的氨挥发特征进行了研究。结果表明,尿素二次加工产品的氨挥发损失特征各不相同:尿素、复合肥料、包膜尿素、包膜复合肥的氨挥发分别占总施氮量的9.2%、10.4%、7.6%、9.3%;复合肥料氨挥发损失比尿素高12.9%,而包膜尿素的氨挥发损失较尿素低17.9%。包膜复合肥与尿素相比,二者氨挥发总体上接近,但在施肥后前25 d包膜复合肥降低氨挥发15.6%,降雨后25 d却增加氨挥发20.7%。尿素二次加工产品的氨挥发损失特征需结合其生产工艺进行进一步研究。     

Ammonia volatilization from urea-treated pasture and tillage soils: effects of soil properties

Mean NH₃ losses after nine days incubation at 18°C and 60% FC were 3.1±2.9% and 7.6±6.0% of applied urea-N from the pasture and tillage counterparts of 10 soil series. These losses were highly correlated with buffered CEC and maximal pH values (pH_m) generated three days after urea application. NH₃ volatilization was apparently controlled by buffered CEC and initial pH (R²= 72–87%) and was related to variations in soil organic matter and texture (R²= 77–81%). Losses in the acid pasture soils were attributed largely to initial pH differences, and in the tillage soils to buffered CEC only. Evolution was greater from the tillage than from the pasture equivalent in eight series. This was attributed to differences in CEC, including buffered CEC and pH-dependent charge, caused by differences in OM content primarily but also in texture between the two soil groups. Differences in NH₃ evolution from urea in pasture and tillage soils, in general, are not related to pH differences.     

基于文献分析的北方冬麦田氨挥发特性

中国北方地区是冬小麦-夏玉米种植体系的主要集约化农业区,过去30多年间化学氮肥投入量大和肥料利用率低的现象较为普遍,氨挥发等农业面源污染严重,需要对冬小麦生长过程中的氨挥发规律及测定方法等进行系统研究。该研究对1980年至2018年的华北平原冬小麦氨挥发文献进行研究总结,采用回归方程和T检验等统计学方法分析了不同施氮水平、施肥时期和测定方法对冬小麦氨挥发的影响。研究发现,随着化肥施氮量的增加,冬小麦氨挥发累积量呈现指数函数增加趋势(y=2.64e0.006 6x),净氨挥发量呈现幂函数增加特征(y=0.004 8x1.358 9)。不考虑激发效应的净氨挥发量比考虑激发效应的高估约21.8%。冬小麦生产中,基追比为1∶1的情况下,基肥期氨挥发量显著高于追肥期氨挥发量(P<0.05),占整个生育期氨挥发量分别为58.7%和41.3%。在180 kg/hm2氮肥水平时,海绵吸收法与真空抽气法测定的氨挥发数量无显著性差异。冬小麦季的氨挥发控制,应该重点通过优化氮肥施用数量,主要在基肥期进行控制。田间生产中,采用海绵吸收法和真空抽气法监测氨挥发应考虑不同施肥水平下的高估。     

Ammonia volatilization from five nitrogen compounds used as fertilizers following surface application to soils

Measurements were made of the volatilization of ammonia from mono-ammonium phosphate (MAP), di-ammonium phosphate (DAP), ammonium sulphate (AS), ammonium nitrate (AN) and urea, applied to the surface of five contrasting soils. The compounds were applied as solids, at a rate equivalent to 100 kg N ha^?1, to samples of moist soil packed into columns (48 mm diameter) and placed individually in jars through which a stream of air was passed for a period of 8 d. Volatilization ranged from nil to 53% of the N applied, with both the nature of the compound and soil type having large effects. Taking all combinations into account, there was a close relationship between the extent of volatilization, expressed as a percentage of the ammonium or urea N, and the pH attained after 24 h by the corresponding mixtures of soil and compound. Using the results of these and other experiments, the proportion of fertilizer N volatilized as ammonia is estimated to be about 3.4% over the UK as a whole.     

典型红壤区稻田树脂包膜控释氮肥氨挥发研究

本文研究了红壤水稻土上,树脂包膜尿素(控释N肥)和普通尿素施用后氨挥发损失的过程及数量。结果表明:①基施后2～4天内和追施后的1～2天内,控释N肥氨挥发通量相对普通尿素处理均有下降,下降幅度分别为28.57%和25.00%;控释N肥氨挥发峰值分别于基肥后第5天和追肥后第4天出现,均滞后于普通尿素处理。②追肥2天后,控释N肥氨挥发通量极显著高于普通尿素处理。因此,只有采取合理的基施方式,控释N肥才能比普通尿素发挥更大的环境效益。     

腐植酸尿素氨挥发特性及影响因素研究

采用室内模拟,研究了腐植酸尿素在土壤培养条件下其氨挥发特性及其与土壤脲酶活性、氮溶出率以及土壤铵态氮、硝态氮含量变化的关系。结果表明,研制的4种腐植酸尿素氨挥发量分别比普通尿素降低了48.14%、 47.99%、 30.89%、 59.22%,其中水溶性腐植酸含量11.78%的腐植酸尿素降低最多。腐植酸尿素降低氨挥发量与其养分释放模式和形成的土壤环境密切相关。土壤氨挥发总量与脲酶活性在培养前期相关系数较高,培养48和96 h分别达到0.825和0.808; 土壤氨挥发总量与肥料累积溶出量相关系数为0.903; 培养前期,土壤氨挥发量与铵态氮含量相关系数达到0.869。     

华北平原水浇玉米-小麦轮作农田氨挥发与反硝化损失

Ammonia (NH3) volatilization, denitriflcation 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 denitriflcation 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. Denitriflcation 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.     

太湖地区乌栅土稻田氨挥发损失的研究

采用连续气流密闭室法,探讨了苏南太湖地区乌栅土稻田3个不同施肥时期施用尿素后的NH3挥发损失规律、有机肥对NH3挥发的影响及稻田NH3挥发量与田面水中NH4 -N浓度的相关性。结果表明,不同施肥处理2005年和2006年稻季NH3挥发量分别为8.2~28.7kg/hm2和21.8~62.1kg/hm2,各占尿素施用量的3.7%~8.8%和10.0%~18.9%。NH3挥发率以分蘖肥最高,穗肥最低,且挥发过程主要发生在施肥后的3d内。秸秆有激发尿素快速分解作用,但对NH3挥发总量影响不大。猪粪的促进生长作用较缓慢,但增加了NH3挥发量。稻田NH3挥发量与田面水中NH4 -N浓度呈线性正相关,且达到极显著水平。     

Ammonia volatilization and carbon dioxide emission from poultry litter: Effects of fractionation and storage time

Abstract

In many poultry producing areas, the amounts of poultry litter generated exceeds the amounts needed for application to soil, as fertilizer, at environmentally safe rates. To reduce the amounts of litter produced, Ndegwa et al. (1991) proposed fractionating the litter to generate a fine fraction that could be used as fertilizer, and a coarser fraction that could be recycled into poultry houses as bedding material. Because the fine fraction may need to be stored for several months before land application, knowledge of the changes that occur during storage would be important from the point of view of litter utilization. The objective of this study was to monitor water and inorganic nitrogen (N) contents, as well as potential ammonia (NH₃) volatilization and carbon dioxide (CO₂) emission in samples of whole litter and fine fraction stored in an unheated building for 16 weeks. Potential NH₃ volatilization and CO₂ emission were measured at unamended water contents and at a water content of 0.5 kg kg^‐1. Water and inorganic N contents of the whole litter and fine fractions showed some fluctuations during the first 4 weeks, but remained relatively stable from weeks 4 to 16. At unamended water contents, potential NH₃ volatilization and CO₂ emission were relatively low and similar for the whole litter and the fine fraction. Also, potential NH₃ volatilization remained stable whereas CO₂ emission decreased with time. Increasing the water content to 0.5 kg kg^‐1significantly increased potential NH₃ volatilization and CO₂ emission in the whole litters and fine fractions, with larger increases usually observed in the fine fractions. At 0.5 kg kg^‐1, both potential NH₃ volatilization and CO₂emission decreased with time. These results suggest that the fine fraction and the whole litter should be stored at relatively low water contents to prevent N losses through NH₃ volatilization and possibly denitrification.     

太湖水稻土麦季尿素氨挥发损失

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 fertilizer and mainly during the period after basal fertilizer application, which accounted for more than 80% of the total ammonia volatilization over the entire wheat growth period. Regression analysis showed that ammonia volatilization was affected mainly by pH and NH4^ -N concentration of the surface soil and air temperature.Ammonia volatilization flux was significantly correlated with pH and NH4^ -N concentration of the surface soil and with daily air average temperature and highest temperature. Thus, application of urea N fertilizer to wheat should consider the characteristics of ammonia volatilization in different periods of N application so as to reduce ammonia losses.     

嘉兴地区稻田氨挥发及其影响因素的研究

氨挥发是稻田氮损失的重要途径之一,掌握氨挥发规律及主要影响因素对于氮损失的评估及调控具有重要意义。为揭示嘉兴地区稻田氨挥发主要发生规律,采用间歇密闭式抽气法,研究了不同施肥期、化学施氮量及有机肥施用、田面水NH+4-N浓度等因素对该地区2013年稻田氨挥发速率的影响。结果表明,基肥期各施肥处理下的氨挥发速率逐日降低,氨挥发主要发生在施肥后前5 d,温度骤降和降雨是造成穗肥期氨挥发速率出现波动性的主要原因,氨挥发速率均小于N 5 kg·hm-2·d-1,较基肥期有明显下降;施氮量与氨挥发总量具有显著的线性正相关性,不同施肥处理下的氨挥发比例为17%~28%,N225+M处理对应的氨挥发总量发生跃增,且氨挥发比例最高,增施干鸡粪对氨挥发的促进作用不大。从氮肥高效利用及低损耗的角度出发,本试验中尿素氮肥施用量应低于N 225 kg·hm-2,加强水氮协调也是降低稻田氮素损失的重要手段之一。     

典型双季稻田基施碳酸氢铵和尿素的氨挥发损失研究

采用密闭室连续抽气法研究了湖南典型双季稻田,尿素和碳酸氢铵基施后的氨挥发特征。结果表明,基施碳酸氢铵(NC)稻田初始氨挥发强度和氨挥发总量大于基施尿素(UR)稻田。早稻季NC处理稻田氨挥发排放量为45.19 kg·hm-2,损失率达30.12%,UR处理氨挥发排放量为32.93 kg·hm-2,损失率达21.95%;晚稻季NC处理稻田氨挥发排放量为70.91 kg·hm-2,损失率达31.93%,UR处理氨挥发排放量为61.78 kg·hm-2,损失率达27.04%。基施尿素能够显著降低稻田氨挥发排放,减少氮素损失。     

节水灌溉稻田氨挥发损失及影响因素

为了揭示节水灌溉稻田氨挥发特征,开展了不同灌溉模式稻田氨挥发损失的田间试验,分析了节水灌溉稻田氨挥发速率季节变化规律与稻季氨挥发损失量,以及稻田氨挥发速率与影响因素之间的相互关系。结果表明,控制灌溉稻田氨挥发速率与淹水灌溉稻田变化规律基本一致,且在分蘖肥引起氨挥发出现峰值后的大部分时间里都要低于淹水灌溉;控制灌溉与淹水灌溉稻田稻季氨挥发损失总量（以纯氮计）分别为125.27 kg/hm2和145.64 kg/hm2,分别占稻季施氮量的31.06%和36.11%。除了受施肥影响外,稻田氨挥发还与田面水（表层土壤水）铵态氮浓度、空气温度、风速、日照时数及空气湿度等有密切关系。与淹水灌溉相比,控制灌溉减少了稻田氨挥发损失。