Keywords

Nitrous oxide; Landscape-DNDC; regional simulations; arable soils; Scotland

Location

Session B2: Advances in Agricultural Modelling

Start Date

11-7-2016 11:30 AM

End Date

11-7-2016 11:50 AM

Abstract

Nitrous oxide (N2O) is a major greenhouse gas whose largest anthropogenic source is the addition of nitrogenous fertilisers to cultivated soils. The development and application of mechanistic models of soil biogeochemistry contributes significantly to the effort to understand and quantify those N2O fluxes. Soil biogeochemistry models are complex and can be particularly difficult to evaluate because N2O measurements are usually sporadic and contain large uncertainties. Therefore, large-scale simulations with such models can be demanding. The majority of model-based studies focus on small spatial scales (i.e. field, catchment) despite the fact that simulations at larger scales are those that offer more applicable and policy-relevant results. In this context, this presentation will provide a picture of N2O emissions from the arable soils of Scotland, including an appraisal of the uncertainty around them. The regional estimates are a product of a PhD project that uses a biogeochemical model (Landscape-DNDC) and benefits from extensive field data and detailed soil and crop geo- datasets. The study resulted in a N2O emission factor (EF) that is significantly smaller than the generic IPCC EF but is inline with the recently estimated UK-specific EF. The presentation will also provide an overview of the model's evaluation and calibration that preceded the regional simulations.

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Jul 11th, 11:30 AM Jul 11th, 11:50 AM

Simulating regional-scale soil nitrous oxide emissions in Scotland

Session B2: Advances in Agricultural Modelling

Nitrous oxide (N2O) is a major greenhouse gas whose largest anthropogenic source is the addition of nitrogenous fertilisers to cultivated soils. The development and application of mechanistic models of soil biogeochemistry contributes significantly to the effort to understand and quantify those N2O fluxes. Soil biogeochemistry models are complex and can be particularly difficult to evaluate because N2O measurements are usually sporadic and contain large uncertainties. Therefore, large-scale simulations with such models can be demanding. The majority of model-based studies focus on small spatial scales (i.e. field, catchment) despite the fact that simulations at larger scales are those that offer more applicable and policy-relevant results. In this context, this presentation will provide a picture of N2O emissions from the arable soils of Scotland, including an appraisal of the uncertainty around them. The regional estimates are a product of a PhD project that uses a biogeochemical model (Landscape-DNDC) and benefits from extensive field data and detailed soil and crop geo- datasets. The study resulted in a N2O emission factor (EF) that is significantly smaller than the generic IPCC EF but is inline with the recently estimated UK-specific EF. The presentation will also provide an overview of the model's evaluation and calibration that preceded the regional simulations.