Disaggregated greenhouse gas emission inventories from agriculture via a coupled economic-ecosystem model

• Published in: Agriculture, ecosystems & environment ecosystems & environment, 2006-02, Vol.112 (2), p.233-240
• Main Authors: Neufeldt, Henry, Schäfer, Michael, Angenendt, Elisabeth, Li, Changsheng, Kaltschmitt, Martin, Zeddies, Jürgen
• Format: Article
• Language: English
• Subjects: Agricultural production systems; air pollution; carbon; carbon dioxide; carbon sequestration; Coupled economic-ecosystem model; crop production; econometric models; environmental models; gas emissions; Greenhouse gas emissions; greenhouse gases; livestock production; manure storage; model validation; nitrogen; pollution control; production technology; rumen fermentation; soil; soil nutrient dynamics; Stocking rates
• ISSN: 0167-8809; 1873-2305
• DOI: 10.1016/j.agee.2005.08.024

Estimates of regional greenhouse gas emissions from agricultural systems are needed to evaluate possible mitigation strategies with respect to environmental effectiveness and economic feasibility. Therefore, in this study, we used the GIS-coupled economic-ecosystem model EFEM–DNDC to assess disaggregated regional greenhouse gas (GHG) emissions from typical livestock and crop production systems in the federal state of Baden-Württemberg, Southwest Germany. EFEM is an economic farm production model based on linear programming of typical agricultural production systems and simulates all relevant farm management processes and GHG emissions. DNDC is a process-oriented ecosystem model that describes the complete biogeochemical C and N cycle of agricultural soils, including all trace gases. Direct soil emissions were mainly related to N 2O, whereas CH 4 uptake had marginal influence (net soil C uptake or release was not considered). The simulated N 2O emissions appeared to be highly correlated to N fertilizer application ( R 2 = 0.79). The emission factor for Baden-Württemberg was 0.97% of the applied N after excluding background emissions. Analysis of the production systems showed that total GHG emissions from crop based production systems were considerably lower (2.6–3.4 Mg CO 2 eq ha −1) than from livestock based systems (5.2–5.3 Mg CO 2 eq ha −1). Average production system GHG emissions for Baden-Württemberg were 4.5 Mg CO 2 eq ha −1. Of the total 38% were derived from N 2O (direct and indirect soil emissions, and manure storage), 40% were from CH 4 (enteric fermentation and manure storage), and 22% were from CO 2 (mainly fertilizer production, gasoline, heating, and additional feed). The stocking rate was highly correlated ( R 2 = 0.85) to the total production system GHG emissions and appears to be a useful indicator of regional emission levels.