Emissions of the
greenhouse gas (GHG) nitrous oxide (N2O) from human activities are
contributing to global climate change.
An estimated 29% of Ireland’s
GHG emissions are from the agricultural sector, and N2O makes up
approximately half of these. Nitrogen (N)
fertilizer use, land-use and climate are major controlling factors of N2O emissions from agricultural lands and these factors
are expected to change in the near future.
The objective of this study is to predict the impact of changing N fertilizer use, land-use and climate
on N2O emissions.
To this end, a set of management, land use, and climate scenarios has
been developed. The current N
input from fertilizers was provided on county scale. Scenarios of altered N
fertilizer applications were then developed to reflect ongoing and future
changes in the farm nutrient management in response to increased
uptake of voluntary environmental
protection measures (e.g. REPS) or mandatory regulations (e.g. Nitrates
Directive). Predictions of future Irish land-use (provided
by the ATEAM project) and climatic changes (from the C4I project) based
on the Intergovernmental Panel on Climate Change A2 and B2 scenarios were used.
To estimate N2O emission under the scenarios, data of N
fertilizer use, land-use, and climate changes were applied to a climate
sensitive N2O emission factor methodology. In
this presentation, we will present the N2O emissions predicted under
the scenarios. It is envisaged that the results will improve our understanding of
the effects of nutrient management on N2O emissions under future changed land-use and climate conditions.