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1.
Marquina Sorena Pérez Tibisay Donoso Loreto Giuliante Adriana Rasse Rafael Herrera Francisco 《Nutrient Cycling in Agroecosystems》2015,101(1):123-137
Nutrient Cycling in Agroecosystems - The largest share of Latin American and Caribbean (LAC) anthropogenic greenhouse gases is derived from land use changes as well as forestry and agriculture,... 相似文献
2.
De Rosa Daniele Rowlings David W. Fulkerson Bill Scheer Clemens Friedl Johannes Labadz Martin Grace Peter R. 《Nutrient Cycling in Agroecosystems》2020,116(3):299-312
Nutrient Cycling in Agroecosystems - The rational nitrogen (N) application rate for crops depends not only on yield but also on the environmental cost of N loss to the... 相似文献
3.
Effect of crop-specific field management and N fertilization on N2O emissions from a fine-loamy soil 总被引:1,自引:0,他引:1
R. Ruser H. Flessa R. Schilling F. Beese J.C. Munch 《Nutrient Cycling in Agroecosystems》2001,59(2):177-191
Agricultural soils are a major source of atmospheric N2O. This study was conducted to determine the effect of different crop-specific field management and N fertilization rates
on N2O emissions from a fine-loamy Dystric Eutrochrept. Fluxes of N2O were measured for two years at least once a week on plots cropped with potatoes (Solanum tuberosum) fertilized with 50 or 150 kg N ha−1 a−1, winterwheat (Triticum aestivum) fertilized with 90 or 180 kg N ha−1 a−1, corn (Zea mays) fertilized with 65 or 130 kg N ha−1 a−1, and on an unfertilized, set-aside soil planted with grass (mainly Lolium perenne and Festuca rubra). The mean N2O emission rate from the differently managed plots was closely correlated to the mean soil nitrate content in the Ap horizon
for the cropping period (April to October, r
2 = 0.74), the winter period (November to March, r
2 = 0.93, one outlier excluded), and the whole year (r
2 = 0.81). N2O emissions outside the cropping period accounted for up to 58% of the annual emissions and were strongly affected by frost-thaw
cycles. There was only a slight relationship between the amount of fertilizer N applied and the annual N2O emission (r
2 = 0.20). The mean annual N2O-N emission from the unfertilized set-aside soil was 0.29 kg ha−1. The annual N2O-N emission from the fertilized crops for the low and the recommended rates of N fertilization were 1.34 and 2.41 kg ha−1 for corn, 2.70 and 3.64 kg ha−1 for wheat, and 5.74 and 6.93 kg ha−1 for potatoes. The high N2O emissions from potato plots were due to (i) high N2O losses from the interrow area during the cropping season and (ii) high soil nitrate contents after the potato harvest. The
reduction of N fertilization (fertilizer was applied in spring and early summer) resulted in decreased N2O emissions during the cropping period. However, the emissions during the winter were not affected by the rate of N fertilization.
The results show that the crop-specific field management had a great influence on the annual N2O emissions. It also affected the emissions per unit N fertilizer applied. The main reasons for this crop effect were crop-specific
differences in soil nitrate and soil moisture content.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
A review of the N2O-N emission from crop residues was conducted based on new data published during the last decade. The result indicated that factors as type of crop, biochemical quality of residues, agricultural management, climate and season of the year, soil properties and soil moisture play a significant role in the rate of N2O-N emissions. An emission factor (EF) equal to 1.055% of N applied in plant residues – derived from a simple linear regression of emitted N2O-N (kg ha?1) on N applied in crop residues (kg ha?1) – represent an estimate that explains about 60% of emission variations. However, the EF of N applied in plant residues is not a constant but a variable coefficient that depends on environmental and management variables. The following two linear models – that estimate emitted N2O-N (kg ha?1) as a function of the variables N (kg ha?1) applied in plant residues (NPR), rain (mm), temperature (°C) and temperature2(°C2) – were fitted to the dataset with 45 observations obtained from the reviewed literature. $$\hskip1.5pc\hbox{N}_{2}\hbox{O}\hbox{-}\hbox{N}=-4.154+0.00955\hbox{ NPR}+1.7278\hbox{ ApM}+0.003996\hbox{ Rain }+0.6242\hbox{ Tem }-0.0230\hbox{ Tem}^{2}$$ and $$\hbox{N}_{2}\hbox{O}\hbox{-}\hbox{N}= 0.6535 + [-0.0404 + 0.0078\hbox{ ApM }+ 0.000044\hbox{ Rain }+ 0.00567\hbox{ Tem }-0.0001975\hbox{ Tem}^{2}]\hbox{ NPR }$$ Both models provided almost equally good statistical fit to the data, with R 2=0.832 and R 2=0.829, respectively, and most regression coefficients being significant at $P < 0.01$ . Because of its internal structure, the second model is more appealing as it represents N2O-N emission as a transformation that is affected by management and environmental variables. The following expression – that correspond to the quantities in the square bracket at the right hand side of the second model – is the coefficient for the variable N applied in crop residues, and represent the emission factor as a function of application method of plant residues, rain, temperature and temperature2. $$\hskip3.5pc\hbox{EF }=-0.0404+0.0078\hbox{ ApM }+0.000044\hbox{Rain }+0.00567\hbox{ Tem }- 0.0001975\hbox{ Tem}^{2}$$ Standardization of research methodologies and data gathering and reporting, including kind of crop, N content of applied residues, agricultural management, length of the measuring period, climate, soils properties, soil temperature and water content, would facilitate further advances in studies oriented to increase the precision of N2O-N emission estimates. 相似文献
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N2O and NO emissions from different N sources and under a range of soil water contents 总被引:1,自引:0,他引:1
A. del Prado P. Merino J. M. Estavillo M. Pinto C. González-Murua 《Nutrient Cycling in Agroecosystems》2006,74(3):229-243
Emissions of nitrous oxide (N2O) and nitric oxide (NO) have been identified as one of the most important sources of atmospheric pollution from grasslands. Soils are major sources for the production of N2O and NO, which are by-products or intermediate products of microbial nitrification and denitrification processes. Some studies have tried to evaluate the importance of denitrification or nitrification in the formation of N2O or NO but there are few that have considered emissions of both gases as affected by a wide range of different factors. In this study, the importance of a number of factors (soil moisture, fertiliser type and temperature) was determined for N2O and NO emissions. Nitrous oxide and NO evolution in time and the possibility of using the ratio NO:N2O as an indicator for the processes involved were also explored. Dinitrogen (N2) and ammonia (NH3) emissions were estimated and a mass balance for N fluxes was performed. Nitrous oxide and NO were produced by nitrification and denitrification in soils fertilised with and by denitrification in soils fertilised with . Water content in the soil was the most important factor affecting N2O and NO emissions. Our N2O and NO data were fitted to quadratic (r=0.8) and negative exponential (r=0.7) equations, respectively. A long lag phase was observed for the N2O emitted from soils fertilised with (denitrification), which was not observed for the soils fertilised with (nitrification) and was possibly due to a greater inhibiting effect of low temperatures on microbial activity controlling denitrification rather than on nitrification. The use of the NO:N2O ratio as a possible indicator of denitrification or nitrification in the formation of N2O and NO was discounted for soils fertilised with . The N mass balance indicated that about 50 kg N ha−1 was immobilised by microorganisms and/or taken up by plant roots, and that most of the losses ocurred in wet soils (WFPS >60%) as N2 and NH3 losses (>55%). 相似文献
6.
Th.V. Vellinga A. van den Pol-van Dasselaar P.J. Kuikman 《Nutrient Cycling in Agroecosystems》2004,70(1):33-45
The contribution of ploughing permanent grassland and leys to emissions of N2O and CO2 is not yet well known. In this paper, the contribution of ploughing permanent grassland and leys, including grassland renovation, to CO2 and N2O emissions and mitigation options are explored. Land use changes in the Netherlands during 1970–2020 are used as a case study. Three grassland management operations are defined: (i) conversion of permanent grassland to arable land and leys; (ii) rotations of leys with arable crops or bulbs; and (iii) grassland renovation. The Introductory Carbon Balance Model (ICBM) is modified to calculate C and N accumulation and release. Model calibration is based on ICBM parameters, soil organic N data and C to N ratios. IPCC emission factors are used to estimate N2O-emissions. The model is validated with data from the Rothamsted Park Grass experiments. Conversion of permanent grassland to arable land, a ley arable rotation of 3 years ley and 3 years arable crops, and a ley bulb rotation of 6 years ley and one year bulbs, result in calculated N2O and CO2 emissions totalling 250, 150 and 30 ton CO2-equivalents ha–1, respectively. Most of this comes from CO2. Emissions are very high directly after ploughing and decrease slowly over a period of more than 50 years. N2O emissions in 3/3 ley arable rotation and 6/1 ley bulb rotation are 2.1 and 11.0 ton CO2-equivalents ha–1 year–1, respectively. From each grassland renovation, N2O emissions amount to 1.8 to 5.5 ton CO2-equivalents ha–1. The calculated total annual emissions caused by ploughing in the Netherlands range from 0.5 to 0.65 Mton CO2-equivalents year–1. Grassland renovation in spring offers realistic opportunities to lower the N2O emissions. Developing appropriate combinations of ley, arable crops and bulbs, will reduce the need for conversion of permanent pasture. It will also decrease the rotational losses, due to a decreased proportion of leys in rotations. Also spatial policies are effective in reducing emissions of CO2 and N2O. Grassland ploughing contributes significantly to N2O and CO2 emissions. The conclusion can be drawn that total N2O emissions are underestimated, because emissions from grassland ploughing are not taken into account. Specific emission factors and the development of mitigation options are required to account for the emissions and to realise a reduction of emissions due to the changes in grassland ploughing. 相似文献
7.
Ulrike Lebender Mehmet Senbayram Joachim Lammel Hermann Kuhlmann 《Nutrient Cycling in Agroecosystems》2014,100(1):111-120
Nitrogen fertilizers are a major source of nitrous oxide (N2O) emissions from arable soils. The relationship between nitrogen application rates and N2O emissions was evaluated during the growth period of winter wheat (~140 days) at six field sites in north-western Germany. Nitrogen was applied as calcium–ammonium–nitrate, with application rates ranging between 0 and 400 kg N ha?1. One trial was conducted in 2010, three trials in 2011 and two trials in 2012. Additionally, post-harvest N2O emissions were evaluated at two field sites during autumn and winter (2012–2013). The emission factors (during the growth period) varied between 0.10 and 0.37 %. Annual N2O emissions ranged between 0.46 and 0.53 % and were consistently lower across all sites and years than to the IPCC Tier 1 default value (1.0 %). Across all sites and years, the relationship between N2O and N application rate was best described by linear regression even if nitrogen amounts applied were higher than the nitrogen uptake of the crop. Additionally, annual N2O emissions per unit of harvested wheat grain were calculated for two field sites to assess the environmental impact of wheat grain production. Yield-scaled N2O emissions followed a hyperbolic function with a minimum of 177 and 191 g N2O–N t grain yield?1 at application rates of 127 and 150 kg N ha?1, followed by an increase at higher N application rates. This relationship indicates that wheat crop fertilization does not necessarily harm the environment through N2O emissions compared to zero fertilization. Thus, improving nitrogen use efficiency may be the best management practice for mitigating yield-scaled N2O emissions. 相似文献
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Oswald van Cleemput 《Nutrient Cycling in Agroecosystems》1998,52(2-3):187-194
Agricultural practices, soil characteristics and meteorological conditions are responsible for eventual nitrate accumulation in the subsoil. There is a lot of evidence that denitrification occurs in the subsoil and rates up to 60–70 kg ha-1 yr-1 might be possible. It has also been shown that in the presence of Fe2+ (formed through weathering of minerals) and an alkaline pH, nitrate can be chemically reduced. Another possible pathway of disappearance is through the formation of nitrite, which is unstable in acid conditions. With regard to the emission of N2O and N2, it can be stated that all conditions whereby the denitrification process becomes marginal are favourable for N2O formation rather than for N2. Because of its high solubility, however, an important amount of N2O might be transported with drainage water. 相似文献
9.
The solubility of CO2 and N2O in a physical solvent, n-dodecane [C.A. Registry N° 124–18–5], has been measured at 40, 80 and 120°C at pressures up to 9.6 MPa. The experimental results were correlated by the Peng-Robinson (1976) equation of state, and the interaction parameters, the Henry's constants and the N2O analogy parameters were obtained. 相似文献
10.
C. Jambert R. Delmas D. Serça L. Thouron L. Labroue L. Delprat 《Nutrient Cycling in Agroecosystems》1997,48(1-2):105-114
Emissions of nitrogen compounds from heavily fertilized and irrigated maize fields have been studied in the Southwest of France, over an annual cultivation cycle. Strong nitrous oxide emissions from denitrification were observed after application of nitrogen fertilizer. Flux intensity appears to be stimulated by rain or irrigation. Emission algorithms, taking into account both nitrogen input and soil water content were established on the basis of the experimental data set. They allowed us to estimate annual nitrogen loss in the form of nitrous oxide modulated by rainfall. Production of methane is observed at the level of the water table under anoxic conditions. Nevertheless, the net flux between soil and atmosphere is negative for most of the time. When methane is produced, fluxes were very low due to methane oxidation in the soil surface layer. 相似文献
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Nitrous oxide (N2O) emissions were measured over two years from an intensively managed grassland site in the UK. Emissions from ammonium nitrate (AN) and urea (UR) were compared to those from urea modified by various inhibitors (a nitrification inhibitor, UR(N), a urease inhibitor, UR(U), and both inhibitors together, SU), as well as a controlled release urea (CR). N2O fluxes varied through time and between treatments. The differences between the treatments were not consistent throughout the year. After the spring and early summer fertilizer applications, fluxes from AN plots were greater than fluxes from UR plots, e.g. the cumulative fluxes for one month after N application in June 1999 were 5.2 ± 1.1 kg N2O-N ha–1 from the AN plots, compared to 1.4 ± 1.0 kg N2O-N ha–1 from the UR plots. However, after the late summer application, there was no difference between the two treatments, e.g. cumulative fluxes for the month following N application in August 2000 were 3.3 ± 0.7 kg N2O-N ha–1 from the AN plots and 2.9 ± 1.1 kg N2O-N ha–1 from the UR plots. After all N applications, fluxes from the UR(N) plots were much less than those from either the AN or the UR plots, e.g. 0.2 ± 0.1 kg N2O-N ha–1 in June 1999 and 1.1 ± 0.3 kg N2O-N ha–1 in August 2000. Combining the results of this experiment with earlier work showed that there was a greater N2O emission response to rainfall around the time of fertilizer application in the AN plots than in the UR plots. It was concluded that there is scope for reducing N2O emissions from N-fertilized grassland by applying UR instead of AN to wet soils in cool conditions, e.g. when grass growth begins in spring. Applying UR with a nitrification inhibitor could cut emissions further. 相似文献
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Daniel Weymann Reinhard Well Carolin von der Heide Jürgen Böttcher Heiner Flessa Wilhelmus H. M. Duijnisveld 《Nutrient Cycling in Agroecosystems》2009,85(3):299-312
Production and accumulation of the major greenhouse gas nitrous oxide (N2O) in surface groundwater might contribute to N2O emissions to the atmosphere. We report on a 15N tracer study conducted in the Fuhrberger Feld aquifer in northern Germany. A K15NO3 tracer solution (60 atom%) was applied to the surface groundwater on an 8 m2 measuring plot using 45 injection points in order to stimulate production of 15N2O by denitrification and to detect its contribution to emissions at the soil surface. Samples from the surface groundwater, from the unsaturated zone and at the soil surface were collected in regular intervals over a 72-days period. Total N2O fluxes at the soil surface were low and in a range between ?7.6 and 29.1 μg N2O-N m?2 h?1. 15N enrichment of N2O decreased considerably upwards in the profile. In the surface groundwater, we found a 15N enrichment of N2O between 13 and 42 atom%. In contrast, 15N enrichment of N2O in flux chambers at the soil surface was very low, but a detectable 15N enrichment was found at all sampling events. Fluxes of groundwater-derived 15N-N2O were very low and ranged between 0.0002 and 0.0018 kg N2O-N ha?1 year?1, indicating that indirect N2O emissions from the surface groundwater of the Fuhrberger Feld aquifer occurring via upward diffusion are hardly significant. Due to these observations we concluded that N2O dynamics at the soil–atmosphere interface is predominantly governed by topsoil parameters. However, highest 15N enrichments of N2O throughout the profile were obtained in the course of a rapid drawdown of the groundwater table. We assume that such fluctuations may enhance diffusive N2O fluxes from the surface groundwater to the atmosphere for a short time. 相似文献
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W.N. Smith B. Grant R.L. Desjardins R. Lemke C. Li 《Nutrient Cycling in Agroecosystems》2004,68(1):37-45
The DNDC model was used to estimate direct N2O emissions from agricultural soils in Canada from 1970 to 1999. Simulations were carried out for three soil textures in seven soil groups, with two to four crop rotations within each soil group. Over the 30-year period, the average annual N2O emission from agricultural soils in Canada was found to be 39.9 Gg N2O–N, with a range from 20.0 to 77.0 Gg N2O–N, and a general trend towards increasing N2O emissions over time. The larger emissions are attributed to an increase in N-fertilizer application and perhaps to a trend in higher daily minimum temperatures. Annual estimates of N2O emissions were variable, depending on timing of rainfall events and timing and duration of spring thaw events. We estimate, using DNDC, that emissions of N2O in eastern Canada (Atlantic Provinces, Quebec, Ontario) were approximately 36% of the total emissions in Canada, though the area cropped represents 19% of the total. Over the 30-year period, the eastern Gleysolic soils had the largest average annual emissions of 2.47 kg N2O–N ha–1 y–1 and soils of the dryer western Brown Chernozem had the smallest average emission of 0.54 kg N2O–N ha–1 y–1. On average, for the seven soil groups, N2O emissions during spring thaw were approximately 30% of total annual emissions. The average N2O emissions estimates from 1990 to 1999 compared well with estimates for 1996 using the IPCC methodology, but unlike the IPCC methodology our modeling approach provides annual variations in N2O emissions based on climatic differences. 相似文献
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Emissions of NOx, NH3 and N2O from anthropogenic activities in India have been estimated based on actual field measurements as well as available default methodologies. The NOx emissions are mainly from the transport sector and contribute about 5% of the global NOx emission from fossil fuel. NH3 emissions from urea seems to be highly uncertain. However, emissions of NH3 from fertilizers and livestock are estimated to be 1175 Gg and 1433 Gg, respectively. N2O emissions seem to be derived predominantly from fertilizer applications, resulting in the release of 199–279 Gg N2O. Other sources of N2O, viz. agricultural residue burning, biomass burning for energy and nitric acid production are estimated to be 3, 35–187 and 2–7 Gg, respectively. 相似文献
20.
Fluxes of NO and N2O from temperate forest soils: impact of forest type, N deposition and of liming on the NO and N2O emissions 总被引:5,自引:0,他引:5
K. Butterbach-Bahl R. Gasche L. Breuer H. Papen 《Nutrient Cycling in Agroecosystems》1997,48(1-2):79-90
Annual cycles of NO, NO2 and N2O emission rates from soil were determined with high temporal resolution at a spruce (control and limed plot) and beech forest site (Höglwald) in Southern Germany (Bavaria) by use of fully automated measuring systems. The fully automated measuring system used for the determination of NO and NO2 flux rates is described in detail. In addition, NO, NO2 and N2O emission rates from soils of different pine forest ecosystems of Northeastern Germany (Brandenburg) were determined during 2 measuring campaigns in 1995. Mean monthly NO and N2O emission rates (July 1994–June 1995) of the untreated spruce plot at the Höglwald site were in the range of 20–130 µg NO-N m-2 h-1 and 3.5–16.4 µg N2O-N m-2 h-1, respectively. Generally, NO emission exceeded N2O emission. Liming of a spruce plot resulted in a reduction of NO emission rates (monthly means: 15–140 µg NO-N m-2 h-1) by 25-30% as compared to the control spruce plot. On the other hand, liming of a spruce plot significantly enhanced over the entire observation period N2O emission rates (monthly means: 6.2–22.1 µg N2O-N m-2 h-1). Contrary to the spruce stand, mean monthly N2O emission rates from soil of the beech plot (range: 7.9–102 µg N2O-N m-2 h-1) were generally significantly higher than NO emission rates (range: 6.1–47.0 µg NO-N m-2 h-1). Results obtained from measuring campaigns in three different pine forest ecosystems revealed mean N2O emission rates between 6.0 and 53.0 µg N2O-N m-2 h-1 and mean NO emission rates between 2.6 and 31.1 µg NO-N m-2 h-1. The NO and N2O flux rates reported here for the different measuring sites are high compared to other reported fluxes from temperate forests. Ratios of NO/N2O emission rates were >> 1 for the spruce control and limed plot of the Höglwald site and << 1 for the beech plot. The pine forest ecosystems showed ratios of NO/N2O emission rates of 0.9 ± 0.4. These results indicate a strong differentiating impact of tree species on the ratio of NO to N2O emitted from soil. 相似文献