Tools for quantifying N2O emissions from agroecosystems

Abstract The importance of constraining the global budget of nitrous oxide (N 2 O) has been well established. The current global estimate of the contribution of N 2 O to total anthropogenic greenhouse gas emissions from agriculture is about 69%. Considerable progress has been made over the past few years in developing tools for quantifying the emissions from agricultural sources, at the local and field scale (i.e., chamber and tower-based measurements) as well as at the landscape and regional levels (i.e., aircraft-based measurement and modelling). However, aggregating these emissions over space and time remains a challenge because of the high degree of temporal and spatial variability. Emissions of N 2 O in temperate climate are largely event driven, e.g., in Eastern Canada, large emissions are observed right after snowmelt. The average emissions during the snowmelt period vary considerably, reflecting the influence of many controlling factors. Cumulative emissions reported here range from 0.05 kg N 2 O-N ha −1 in Western Canada to 1.26 kg N 2 O-N ha −1 in Eastern Canada, values that reflect differences in climatic zones and fertilizer management practices. This paper describes the tools for refining the global N 2 O budget and provides examples of measurements at various scales. Tower-based and aircraft measurement platforms provide good data for quantifying the variability associated with the measurements. Chamber-based methods lack the temporal and spatial resolution required to follow the event driven nature of N 2 O fluxes but provide valuable information for evaluating management practices. The model DeNitrification and DeComposition is an example of a technique to estimate N 2 O emissions when no data is available.

[1]  F. Beese,et al.  Nitrous oxide emissions from frozen soils under agricultural, fallow and forest land , 2000 .

[2]  J. I. MacPherson,et al.  Aircraft-Based Flux Sampling Strategies , 2006 .

[3]  W. Parton,et al.  Generalized model for N2 and N2O production from nitrification and denitrification , 1996 .

[4]  D. Keeney,et al.  Nitrous Oxide Production throughout the Year from Fertilized and Manured Maize Fields , 1987 .

[5]  G. L. Hutchinson,et al.  Improved Soil Cover Method for Field Measurement of Nitrous Oxide Fluxes , 1981 .

[6]  D. Burton,et al.  Profile nitrous oxide and carbon dioxide concentrations in a soil subject to freezing , 1994 .

[7]  David Chadwick,et al.  Greenhouse gas emissions from agriculture , 1999 .

[8]  J. I. MacPherson,et al.  Upscaling chamber-based measurements of N2O emissions at snowmelt , 2005 .

[9]  J. Pomeroy,et al.  Thick ice layers in snow and frozen soil affecting gas emissions from agricultural soils during winter , 2001 .

[10]  Ward N. Smith,et al.  Estimated N2O and CO2 Emissions as Influenced by Agricultural Practices in Canada , 2004 .

[11]  C. Wagner-Riddle,et al.  Nitrous oxide emissions from agricultural fields during winter and spring thaw as affected by management practices , 1998, Nutrient Cycling in Agroecosystems.

[12]  S. McGinn,et al.  Methods for Measuring Soil-Surface Gas Fluxes , 2005 .

[13]  D. Keeney,et al.  NITROUS OXIDE EMISSIONS FROM SOILS DURING THAWING , 1984 .

[14]  A. Palojärvi,et al.  Overwinter greenhouse gas fluxes in two contrasting agricultural habitats , 2004, Nutrient Cycling in Agroecosystems.

[15]  C. Paulson.  The Mathematical Representation of Wind Speed and Temperature Profiles in the Unstable Atmospheric Surface Layer , 1970 .

[16]  J. Gash,et al.  A note on estimating the effect of a limited fetch on micrometeorological evaporation measurements , 1986 .

[17]  E. K. Webb,et al.  Correction of flux measurements for density effects due to heat and water vapour transfer , 1980 .

[18]  E. T. Kanemasu,et al.  Tunable diode laser measurements of methane fluxes from an irrigated rice paddy field in the Philippines , 1995 .

[19]  G. W. Thurtell,et al.  Micrometeorological measurements of methane and nitrous oxide exchange above a boreal aspen forest , 1997 .

[20]  G. W. Thurtell,et al.  Micrometeorological measurements of trace gas fluxes from agricultural and natural ecosystems , 1996 .

[21]  G. Harris,et al.  Measurements of N2O fluxes from fertilized grassland using a fast response tunable diode laser spectrometer , 1994 .

[22]  W. Parton,et al.  Generalized model for NOx and N2O emissions from soils , 2001 .

[23]  Changsheng Li,et al.  Modeling carbon biogeochemistry in agricultural soils , 1994 .

[24]  Christopher Potter,et al.  Process modeling of controls on nitrogen trace gas emissions from soils worldwide , 1996 .

[25]  B. Grant,et al.  Estimates of the interannual variations of N2O emissions from agricultural soils in Canada , 2004, Nutrient Cycling in Agroecosystems.

[26]  C. Wagner-Riddle,et al.  Winter and Spring Thaw Measurements of N2O, NO and NOx Fluxes using a Micrometeorological Method , 2001 .

[27]  G. W. Thurtell,et al.  Eddy correlation measurements of methane fluxes using a tunable diode laser at the Kinosheo Lake tower site during the Northern Wetlands Study (NOWES) , 1994 .

[28]  K. Minami,et al.  Nitrous oxide emissions from agricultural fields: Assessment, measurement and mitigation , 1996, Plant and Soil.

[29]  Elizabeth Pattey,et al.  Mathematical modeling of nitrous oxide emissions from an agricultural field during spring thaw , 1999 .

[30]  Ward N. Smith,et al.  Testing the DNDC model using N2O emissions at two experimental sites in Canada , 2002 .

[31]  R. Desjardins,et al.  Measuring nighttime CO2 flux over terrestrial ecosystems using eddy covariance and nocturnal boundary layer methods , 2001 .

[32]  A. Bouwman,et al.  Exchange of greenhouse gases between terrestrial ecosystems and the atmosphere , 1990 .

[33]  Elizabeth Pattey,et al.  Towards standards for measuring greenhouse gas fluxes from agricultural fields using instrumented towers , 2006 .

[34]  Monique Y. Leclerc,et al.  Footprint prediction of scalar fluxes from analytical solutions of the diffusion equation , 1990 .

[35]  N. Bertrand,et al.  Winter fluxes of greenhouse gases from snow‐covered agricultural soil:intra‐annual and interannual variations , 2000 .

[36]  R. C. Izaurralde,et al.  Tillage and N-source influence soil-emitted nitrous oxide in the Alberta Parkland region , 1999 .

[37]  R. Desjardins,et al.  Accuracy of the relaxed eddy-accumulation technique, evaluated using CO2 flux measurements , 1993 .

[38]  R. C. Izaurralde,et al.  Seasonal distribution of nitrous oxide emissions from soils in the Parkland region , 1998 .

[39]  G. W. Thurtell,et al.  A diode laser based gas monitor suitable for measurement of trace gas exchange using micrometeorological techniques , 2003 .

[40]  J. I. MacPherson,et al.  Application of a tunable diode laser to the measurement of CH4 and N2O fluxes from field to landscape scale using several micrometeorological techniques , 2006 .

[41]  F. Beese,et al.  Nitrous oxide emissions from soil during freezing and thawing periods. , 2001 .

[42]  G. W. Thurtell,et al.  Methane Fluxes from a Wetland using the Flux-Gradient Technique The Measurement of Methane Flux from a Natural Wetland Pond and Adjacent Vegetated Wetlands using a TDL-Based Flux-Gradient Technique , 2001 .

[43]  S. Malhi,et al.  Denitrification and nitrous oxide emissions from a Black Chernozemic soil during spring thaw in Alberta , 1997 .

[44]  C. Kessel,et al.  Estimation of annual nitrous oxide emissions from a transitional grassland-forest region in Saskatchewan, Canada , 1999 .

[45]  Changsheng Li,et al.  A model of nitrous oxide evolution from soil driven by rainfall events: 1. Model structure and sensitivity , 1992 .

[46]  David D. Nelson,et al.  Measurement of trace gas fluxes using tunable diode laser spectroscopy , 1995, Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences.

[47]  Elizabeth Pattey,et al.  Modelling variability in N2O emissions from fertilized agricultural fields , 2003 .

[48]  Changsheng Li,et al.  A process-oriented model of N2O and NO emissions from forest soils: 1. Model development , 2000 .

[49]  P. Cellier,et al.  Nitrous oxide fluxes from a fertilised maize crop using micrometeorological and chamber methods , 1999 .

[50]  Dan Pennock,et al.  Development and application of landform segmentation procedures , 2001 .

[51]  B. Hicks,et al.  Wind profile relationships from the ‘wangara’ experiment , 1976 .

[52]  C. Wagner-Riddle,et al.  Estimates of nitrous oxide emissions from agricultural fields over 28 months , 1997 .

[53]  K. King,et al.  Nitrous Oxide and Carbon Dioxide Fluxes from a Bare Soil Using a Micrometeorological Approach , 1996 .

[54]  Joost A. Businger,et al.  Flux measurement with conditional sampling , 1990 .

[55]  Steve Frolking,et al.  A model of nitrous oxide evolution from soil driven by rainfall events: 2. Model applications , 1992 .

[56]  J. I. MacPherson,et al.  Aircraft-based volatile organic compounds flux measurements with relaxed eddy accumulation , 1999 .

[57]  Ewald Schnug,et al.  Nitrous oxide release from arable soil: Importance of N-fertilization, crops and temporal variation , 1998 .