Speaker
Description
Introduction
Reducing greenhouse gas (GHG) emissions from agriculture is crucial in combating climate change, as this sector contributes significantly to overall anthropogenic GHG emissions. In crop production major emissions, stem from the production of Nitrogen (N) fertilizer and related nitrous oxide (N2O) emissions in the field. The broader integration of legumes in crop rotations can potentially support climate change mitigation, as they can fix atmospheric nitrogen through symbiotic relationships with soil bacteria and reduce the reliance on synthetic fertilizers and respectivelyespectiveGHG emissions (van de Noort, 2016). Narrow-leaved lupin (Lupinus angustifolius), a legume well-suited well suited to temperate climates with specific nutritional qualities, has the potential to reduce carbon footprints associated with agriculture and human nutrition (van de Noort, 2016). By processing it into protein-rich plant-based milk and meat substitutes, lupin could significantly contribute to reducing the carbon footprint of the German food sector. In this study, weand hence aim to investigate lupin carbon footprints for various locations and over several years in Germany, to understand how lupin growth patterns relate to GHG emissions and to explore its potential for mitigating climate change in key German growing regions.
Material and Methods
In this study, we analyzed GHG emissions from various lupin genotypes across 14 sites in Germany's main growing regions from 2002 to 2015. Data were sourced from post-registration variety trials published in annual reports by state-level authorities (e.g., Jentsch et al., 2017; Zenk et al., 2017). The dataset includes genotype-, location-, and year-specific yield information (grain yield, thousand kernel mass, grain protein content) and management data (timing, type, and amounts of sowing, fertilization, plant protection measures).
GHG emissions associated with lupin cultivation were quantified using a life cycle assessment (LCA) approach, considering all cultivation stages from land preparation to harvesting. The system boundary was defined from cradle to farm-gate, specifically focusing on GHG emissions. Emissions stemming from material and energetic inputs (e.g., diesel for field operations) were estimated using emission factors from established databases, while N2O emissions were assessed using the IPCC Tier 2 approach. Lupin cultivation for all genotypes, locations, and years was assumed to occur on a 500-hectare farm with an average plot size of 20 hectares and an average farm-to-field distance of four kilometers. Data management and LCA calculations were performed using R Studio to comprehensively quantify GHG emissions. Functional units considered were GHG emissions per unit land (carbon footprint land; CFPL), per unit grain (carbon footprint grain; CFPG), and per unit protein (carbon footprint protein; CFPP). Statistical tests, specifically ANOVA, were utilized to assess significant differences in CFPL, CFPG, and CFPP among genotypes, locations, and years
Results and Discussion
Across numerous combinations of lupin genotypes, locations, and years, the carbon footprint per unit land, grain, and protein was assessed. Notably, N2O emissions were identified as the leading contributor to total greenhouse gas emissions in lupin cultivation, followed by emissions from diesel use, seed sowing, and fertilizer application. GHG emissions stemming from plant protection products comparatively low due to small dosages applied per hectare. Significant differences were observed among genotypes, locations, and years for all functional units investigated (Fig. 1). While there is limited potential to further reduce N2O emissions concerning the carbon footprint per unit land Fig(1), advancements in breeding and management practices could enhance the carbon footprint per unit grain and protein. To comprehensively evaluate the climate change mitigation potential of lupin and other legumes, conducting a life cycle assessment at the crop rotation level is planned, considering lupin's role in substituting mineral nitrogen for the subsequent crop. Additionally, employing agroecosystems models and adopting a model-based Tier 3 approach for estimating N2O emissions will enhance the analysis. Plans also include broadening the assessment to encompass the entire value chain, considering production, transport and processing to different food items, to thoroughly assess the climate change mitigation potential of regionally produced lupin-based proteins.
References
Jentsch, U., Günther, K., Guddat, C. (2017) Landessortenversuche in Thüringen, Blaue Lupin, Versuchsbericht 2016. Thüringer Landesanstalt für Landwirtschaft, Jena; Themenblatt-Nr.: 23.02
Van de Noort, M. (2016) Lupin: An Important Protein and Nutrient Source, Sustainable Protein Sources. Elsevier https://doi.org/10.1016/B978-0-12-802778-3.00010-x
Zenk, A., Pietz, G., Michel, V. (2017) Sommergetreide und Leguminosen 2017, Ergebnisse Landessortenversuche - Anbaugebiet „D-Nord/ MV Süd“. Landesforschungsan
| Keywords | Greenhouse gas emissions; Lupinus angustifolius |
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