Assessing the impacts of tillage and fertilization management on nitrous oxide emissions in a cornfield using the DNDC model

Using a revised Intergovernmental Panel on Climate Change (IPCC) methodology and the process-based model DeNitrification and DeComposition (DNDC), we estimated N2O emissions from agroecosystems in Canada for each census year from 1981 to 2001. Based on the IPCC methodology, direct emissions of N2O ranged from 12.9 to 17.3 with an average of 15.1 Tg CO2 equivalents, while the DNDC model predicted values from 16.0 to 24.3 with an average of 20.8 Tg CO2 equivalents over the same period, and showed a large interannual variation reflecting weather variability. On a provincial basis, emissions estimated by IPCC and DNDC methods were highest in Alberta, Saskatchewan and Ontario, intermediate for Manitoba and Quebec and lowest in British Columbia and the Atlantic provinces. The greatest source of emissions estimated by the IPCC method was from N fertilizer (avg. 6.32 Tg CO2 equiv. in Canada), followed by crop residues (4.24), pasture range and paddocks (PRP) (2.77), and manure (1.65). All sources of emissions, but especially those from fertilizers, increased moderately over time. Monte Carlo Simulation was used to determine the uncertainty associated with the 2001 emission estimates for both IPCC and DNDC methodologies. The simulation generated most likely values of 19.2 and 16.0 Tg CO2 equivalents for IPCC and DNDC, respectively, with uncertainties of 37 and 41%, respectively. Values for the IPCC estimates varied between 28% for PRP and manure and 50% for N fertilizer and crop residues. At the provincial level, uncertainty ranged between 15 and 47% with higher values on the prairies. Sensitivity analyses for IPCC estimates showed crop residues as the most important source of uncertainty followed by synthetic N-fertilizers. Our analysis demonstrated that N2O emissions can be effectively estimated by both the DNDC and IPCC methods and that their uncertainties can be effectively estimated by Monte Carlo Simulation. Key words: Nitrous oxide, IPCC, DNDC model, Uncertainty analysis, Monte Carlo Simulation

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Modeling Nitrous Oxide Emissions From Large-Scale Intensive Cropping Systems in the Southern Amazon

Frontiers in Sustainable Food Systems ◽

10.3389/fsufs.2021.701416 ◽

2021 ◽

Vol 5 ◽

Author(s):

Ciniro Costa ◽

Gillian L. Galford ◽

Michael T. Coe ◽

Marcia Macedo ◽

KathiJo Jankowski ◽

...

Keyword(s):

Nitrous Oxide ◽

Spatial Data ◽

Crop Production ◽

Large Scale ◽

Cropping Systems ◽

Field Measurements ◽

N Fertilization ◽

Nitrous Oxide Emissions ◽

Dndc Model ◽

Mato Grosso

Nitrogen (N) fertilizer use is rapidly intensifying on tropical croplands and has the potential to increase emissions of the greenhouse gas, nitrous oxide (N2O). Since about 2005 Mato Grosso (MT), Brazil has shifted from single-cropped soybeans to double-cropping soybeans with maize, and now produces 1.5% of the world's maize. This production shift required an increase in N fertilization, but the effects on N2O emissions are poorly known. We calibrated the process-oriented biogeochemical DeNitrification-DeComposition (DNDC) model to simulate N2O emissions and crop production from soybean and soybean-maize cropping systems in MT. After model validation with field measurements and adjustments for hydrological properties of tropical soils, regional simulations suggested N2O emissions from soybean-maize cropland increased almost fourfold during 2001–2010, from 1.1 ± 1.1 to 4.1 ± 3.2 Gg 1014 N-N2O. Model sensitivity tests showed that emissions were spatially and seasonably variable and especially sensitive to soil bulk density and carbon content. Meeting future demand for maize using current soybean area in MT might require either (a) intensifying 3.0 million ha of existing single soybean to soybean-maize or (b) increasing N fertilization to ~180 kg N ha−1 on existing 2.3 million ha of soybean-maize area. The latter strategy would release ~35% more N2O than the first. Our modifications of the DNDC model will improve estimates of N2O emissions from agricultural production in MT and other tropical areas, but narrowing model uncertainty will depend on more detailed field measurements and spatial data on soil and cropping management.

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Evaluating management effects on nitrous oxide emissions from grasslands using the process-based DeNitrification–DeComposition (DNDC) model

Atmospheric Environment ◽

10.1016/j.atmosenv.2011.07.046 ◽

2011 ◽

Vol 45 (33) ◽

pp. 6029-6039 ◽

Cited By ~ 18

Author(s):

Rashad Rafique ◽

Matthias Peichl ◽

Deirdre Hennessy ◽

Gerard Kiely

Keyword(s):

Nitrous Oxide ◽

Nitrous Oxide Emissions ◽

Dndc Model ◽

Management Effects

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Assessing the impacts of diversified crop rotation systems on yields and nitrous oxide emissions in Canada using the DNDC model

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.143433 ◽

2021 ◽

Vol 759 ◽

pp. 143433

Author(s):

Rong Jiang ◽

J.Y. Yang ◽

C.F. Drury ◽

Wentian He ◽

W.N. Smith ◽

...

Keyword(s):

Nitrous Oxide ◽

Crop Rotation ◽

Nitrous Oxide Emissions ◽

Dndc Model

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Field Validation of DNDC Model for Methane and Nitrous Oxide Emissions from Rice-based Production Systems of India

Nutrient Cycling in Agroecosystems ◽

10.1007/s10705-005-6111-5 ◽

2006 ◽

Vol 74 (2) ◽

pp. 157-174 ◽

Cited By ~ 75

Author(s):

Y. Jagadeesh Babu ◽

C. Li ◽

S. Frolking ◽

D. R. Nayak ◽

T. K. Adhya

Keyword(s):

Nitrous Oxide ◽

Production Systems ◽

Nitrous Oxide Emissions ◽

Field Validation ◽

Dndc Model

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An improved UK-DNDC model for evaluations of soil temperature and nitrous oxide emissions from Canadian agriculture

Plant and Soil ◽

10.1007/s11104-021-05125-2 ◽

2021 ◽

Author(s):

Dhananjay Yadav ◽

Junye Wang

Keyword(s):

Nitrous Oxide ◽

Soil Temperature ◽

Nitrous Oxide Emissions ◽

Dndc Model

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Evaluation of the DNDC Model to Estimate Soil Parameters, Crop Yield and Nitrous Oxide Emissions for Alternative Long-Term Multi-Cropping Systems in the North China Plain

Agronomy ◽

10.3390/agronomy12010109 ◽

2022 ◽

Vol 12 (1) ◽

pp. 109

Author(s):

Mohamed Abdalla ◽

Xiaotong Song ◽

Xiaotang Ju ◽

Pete Smith

Keyword(s):

Nitrous Oxide ◽

Crop Yield ◽

Crop Yields ◽

Cropping Systems ◽

Pore Space ◽

Nitrous Oxide Emissions ◽

Soil Parameters ◽

N2o Emissions ◽

Dndc Model

Optimizing crop rotations is one of the proposed sustainable management strategies for increasing carbon sequestration. The main aim of this study was to evaluate the DeNitrification-DeComposition (DNDC) model for estimating soil parameters (temperature, moisture and exchangeable NO3− and NH4+), crop yield and nitrous oxide (N2O) emissions for long-term multi-cropping systems in Hebei, China. The model was validated using five years of data of soil parameters, crop yields and N2O emissions. The DNDC model effectively simulated daily soil temperature, cumulative soil nitrogen and crop yields of all crops. It predicted the trends of observed daily N2O emissions and their cumulative values well but overestimated the magnitude of some peaks. However, the model underestimated daily water filled pore space, especially in dry seasons, and had difficulties in correctly estimating daily exchangeable NO3− and NH4+. Both observed and simulated cumulative N2O results showed that optimized and alternative cropping systems used less nitrogen fertiliser, increased grain yield and decreased N2O emissions compared to the conventional cropping system. Our study shows that although the DNDC model (v. 9.5) is not perfect in estimating daily N2O emissions for these long-term multi-cropping systems, it could still be an effective tool for predicting cumulative emissions.

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Testing the DNDC model using N2O emissions at two experimental sites in Canada

Canadian Journal of Soil Science ◽

10.4141/s01-048 ◽

2002 ◽

Vol 82 (3) ◽

pp. 365-374 ◽

Cited By ~ 50

Author(s):

W N Smith ◽

R L Desjardins ◽

B. Grant ◽

C. Li ◽

R. Lemke ◽

...

Keyword(s):

Nitrous Oxide ◽

Management Practices ◽

Agricultural Soils ◽

Nitrous Oxide Emissions ◽

N2o Emissions ◽

Western Canada ◽

Dndc Model ◽

Eastern Canada ◽

Ipcc Methodology ◽

Key Words Nitrous Oxide

Measured data from two experimental sites in Canada were used to test the ability of the DeNitrification and DeComposition model (DNDC) to predict N2O emissions from agricultural soils. The two sites, one from eastern Canada, and one from western Canada, provided a variety of crops, management practices, soils, and climates for testing the model. At the site in eastern Canada, the magnitude of total seasonal N2O flux from the seven treatments was accurately predicted with a slight average over-prediction (ARE) of 3% and a coefficient of variation of 41%. Nitrous oxide emissions based on International Panel for Climate Change (IPCC) methodology had a relative error of 62% for the seven treatments. The DNDC estimates of total yearly emissions of N2O from the field site in western Canada showed an underestimation of 8% for the footslope landscape position and an overestimation of 46% for the shoulder position. The data input for the DNDC model were not of sufficient detail to characterize the moisture difference between the landscape positions. The estimates from IPCC guidelines showed an underestimation of 54% for the footslope and an overestimation of 161% for the shoulder. The results indicate that the DNDC model was more accurate than IPCC methodology at estimating N2O emissions at both sites. Key words: Nitrous oxide, DNDC, soil model, greenhouse gas, testing

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