Danish agriculture can reduce greenhouse gases

With targeted efforts, the Danish agricultural sector can meet the EU requirements regarding the reduction of climate gasses while maintaining food production. More research is necessary to reduce costs.

2016.12.05 | Janne Hansen

Denmark produces food with the one of the world’s lowest climate footprints. However, we need further reductions and we should cooperate with other EU countries to achieve this, Professor Jørgen E. Olesen says. Photo: Janne Hansen

EU requirements demand that the Danish non-quota sectors – i.e. agriculture, transport, buildings and waste – reduce their greenhouse gas emissions by 39 percent before 2030 compared to 2005 levels. Will this be possible for Danish agriculture?

Danish agriculture is highly efficient and its productivity continues to increase, which helps to reduce emissions as long as the agricultural production does not increase. In this connection, the stock of cattle and the size of the dairy production are of particular importance as these contribute more than half of the total agricultural emissions. Significantly greater requirements for emissions reductions could necessitate a reduction of Danish livestock production if no other alternatives are found.

A reduction of the Danish livestock production is not desirable – neither for the agricultural sector, socio-economics nor consumers – or maybe not even for the climate. All things being equal, a reduced Danish food production might result in production moving abroad where greenhouse gas emissions per produced unit are higher than in Denmark.

Focus on climate footprint

It is important to focus on the fact that the agricultural sector should reduce the climate footprint, i.e. greenhouse gases per unit produced, and that this is not the same as reducing total greenhouse gases. The Danish agricultural sector already produces food with one of the lowest climate footprints. Is it possible to significantly reduce agricultural climate gas emissions further?

In answer to this question, expert on climate and agriculture Professor Jørgen E. Olesen of the Department of Agroecology at Aarhus University replies that it is not impossible. The three climate gasses in question are carbon dioxide (CO2), methane and nitrous oxide.

- One of the possibilities is to increase soil carbon stocks, but according to EU climate agreements, carbon stocks may only contribute a four percent reduction of the Danish commitment until 2030. Another possibility is to purchase additional CO2 quotas, but this approach also has an upper limit; the purchase of quotas may only contribute a two percent reduction in greenhouse gas emissions. This means that most of the reduction needs to be found by reducing methane and nitrous oxide emissions, says Jørgen E. Olesen.

Wanted: Magic powder

With regard to methane emissions, the focus needs to be on livestock and manure stores.

- In order to reduce methane emissions from our livestock we need some kind of magic powder, says Jørgen E. Olesen with a twinkle in his eye. Examples of this could be the addition of kelp, oregano or nitrate to cattle feed, since this would reduce enteric methane emissions. New patented products will soon be introduced but we do not know the prices of these yet. Senior Researcher Peter Lund and his colleagues from the Department of Animal Science at Aarhus University currently carry out intensive research within this area.
In connection with reduced methane emissions from manure stores, slurry can be acidified or used for biogas.

Nitrous oxide from fields is a major contributor to Danish greenhouse gas emissions.  

- We also need magic powder in this area. In this case we are looking at nitrification inhibitors, says Jørgen E. Olesen. Søren O. Sørensen from Department of Agroecology carries out research within this particular area but further research funding is necessary to continue. All things considered, we need more research in a number of areas in order for agriculture to be able to reduce emissions.

- We need more research to identify, develop and implement the appropriate magic powders. We also need research on national estimates for nitrous oxide emissions from various types of fertilizers and different soil types. Scientists from Ireland and the UK have demonstrated that significant differences exist. This can be used to reduce costs in relation to reducing emissions. However, we only have limited knowledge of how the situation is under Danish conditions, says Jørgen E. Olesen, and continues:

- We need to examine and develop new cultivation systems that will ensure high-yielding crops in addition to an increased amount of biomass to be stored in the soil. This would also benefit the aquatic environment. Another initiative that may help reduce climate gas emissions – although it requires further knowledge – is the development of new harvest methods, such as early harvest that enables improved establishment of cover crops and increased carbon stocks resulting in increased nitrogen utilization.

Practical application is important

Once the initiatives and mitigations have been identified and developed it is important to motivate the farmers to use them. The solutions should be efficient in relation to greenhouse gas emissions, practically applicable and ensure that the agricultural sector can maintain its high productivity – without being too expensive.

One of the problems in achieving the 39 percent reduction in non-quota sectors is the fact that agricultural biogas is used for energy consumption (electricity and heat) and the energy sector, where it helps to achieve the targets of the quota sector. Therefore, the reduction is not credited to the non-quota sectors. Part of the solution to this could be to use the biogas for substituting diesel in the heavy transport sector. Thereby renewable energy produced in the non-quota sector contributes to reducing other emissions in that sector.

Another problem is that the 39 percent reduction is  a specific reduction requirement for Denmark. When looking at the total European emission accounts, the reduction in agricultural climate gas emissions may be achieved at much lower prices if the initiatives are carried out in countries where the climate footprint is at higher. Therefore, Denmark should continue working for a common European regulation of agricultural emissions.

- Denmark produces food with the one of the world’s lowest climate footprints. However, we need further reductions and we should cooperate with other EU countries to achieve this. Thus, Europe as a whole will be able to reduce climate gas emissions. Therefore, we must focus on European research cooperation in order to solve these problems, says Head of Department, Erik Steen Kristensen, Department of Agroecology at Aarhus University.

Further information

Read more about climate change and agriculture on the theme page 


Professor Jørgen E. Olesen
Department of Agroecology
E-mail: jeo@agro.au.dk
Telephone: +45 8715 7778
Mobile: +45 4082 1659

Climate-Smart Agri-Food Systems is one of the research areas in which the Department of Agroecology is particularly strong and from which results are delivered in line with national and global societal challenges and goals.

Agro, DCA