Eco-innovations in the German fertilizer supply chain: Impact on the carbon footprint of fertilizers

Abstract

The aim of this paper is to analyse to what extent the existing eco-innovations in the German fertilizer domain might reduce the fertilizer carbon footprint without compromising on crop productivity. The continuously growing demand for agricultural products will require a further increase in agricultural production mostly achieved with additional external inputs (fossil energy, pesticides, irrigation water and fertilizers). Fertilizer in general and nitrogen fertilizers in particular are major factors for yield increases in crop production. On the other hand, emissions of greenhouse gases play a dominant role in the debate on the environmental burden of fertilizers. Typical mineral fertilizers were compared with so-called stabilized nitrogen fertilizers and secondary raw material fertilizers in this study. Additionally, an effect of the combination of irrigation with fertilization (i.e. fertigation) was investigated. With an adopted life cycle assessment approach focusing on CO<sub>2</sub> and N<sub>2</sub>O emission, the carbon footprints of the different fertilizer options were considered. The calculations showed that especially the use of stabilized nitrogen fertilizer reduced the fertilization-related carbon footprint up to 13%. However, because of higher costs or incomplete supply chain relationships, adoption of these innovations is expected to be rather limited in the near future. Fertilizers made from secondary raw materials resulted in similar carbon footprints as mineral ones, but they can help to close nutrient cycles and use by-products of other production processes.

Net‐Zero CO2 Germany—A Retrospect From the Year 2050

“…Today, farmers extensively apply techniques such as the state‐of‐the‐art fertilizer, tillage, and irrigation scheme in Germany. Organic fertilizers (OF) are now preferred over mineral fertilizers, because the latter have a larger carbon footprint, and the former return organic material back to the soil (Hasler et al., 2017). OF are applied on soils with highest carbon storage potential or traditionally low OF application, such as crop production areas in East Germany (Don et al., 2018; Lal et al., 2015).…”

Climate mitigation co-benefits from sustainable nutrient management in agriculture

“…The data reveals that reductions of up to 13% could be achieved with stabilised fertilisers, however more needs to be understood about the wider environmental effects. The study by Hasler et al (2017) additionally considered the combination of fertilisers with irrigation (fertigation) as well as secondary raw material fertilisers. It confirms that CO2 emissions are as important as N2O for a lifecycle assessment of the GHGs of mineral fertilisers, as for instance ammonium nitrate (AN) with a N2O emission of 596 kg CO2eq per functional unit in cultivation also involves CO2 emissions of 452 kg CO2 + 105 kg CO2 during production and cultivationbesides a production phase N2O emission of 150 kg CO2eq and 10 kg CO2 in transport.…”