Adjustment of key activity data affecting greenhouse gas emission estimates from agricultural land management in accordance with the requirements of the Intergovernmental Panel on Climate Change (IPCC)

This study presents a methodological refinement of calculating greenhouse gas emissions from agricultural land management in the Czech Republic according to IPCC requirements. The authors utilize the SoilClim model providing input data in a 500 × 500 m grid for finer division of the Czech territory into climate zones according to IPCC. The research analyses the application of nitrogen fertilizers at the district level for the period 2015–2023 instead of national data. Results show significant dynamics of climate zones, where the extent of “dry” areas fluctuated in individual years from 40% to more than 80%. Implementation of the refined model led to a reduction in reported nitrous oxide emissions by an average of more than 9% in the reported period 1990–2023, representing savings of 20 Mt CO2 equivalent. The model-based use of district-level data on fertilizer application led to an additional reduction of 1.2 Mt CO₂ equivalent for the years 2015–2023. The study demonstrates that methodological refinement and the use of region-specific activity data can significantly influence the national greenhouse gas inventory. It highlights the need for continuous updates of calculation methods and activity data to improve the quality of national reporting and provides essential insights for a more effective emission reduction strategy in the agricultural sector of the Czech Republic.