It is entirely possible to reduce greenhouse gas emissions and show greater consideration for the environment – without reducing food production. This is one of the findings of a recent study from the Norwegian University of Science and Technology (NTNU).
"Agricultural activities pose a significant threat to the natural environment," said Francesco Cherubini, professor and Director of the Industrial Ecology Programme at NTNU.
We all need food, but food production currently accounts for a third of the world's greenhouse gas emissions. Agriculture leads to a reduction in biodiversity. In addition, it uses large amounts of water and pollutes rivers, lakes and oceans due to nutrient runoff.
"That is why we need to take action. Agriculture in Europe must become more sustainable. The problem is that the measures being implemented today, such as protecting certain areas or allowing forests to regrow, are competing with food production for areas of land."
Little potential for intensification
Researchers at NTNU have therefore looked for solutions to reduce greenhouse gas emissions and mitigate the loss of biodiversity, without compromising food production.
By allowing natural vegetation to regrow in these 'sub-optimal' areas, while also optimizing production on better agricultural land, the study shows that emissions from agriculture can be reduced by up to 40 per cent.
"In Europe, we already have a rather intensive type of agriculture. There is little to be gained from further intensification. That leaves us with only one option – to stop cultivating the areas that are least suitable for agriculture and move production to better-suited areas. By allowing trees and natural vegetation to repopulate the cultivated areas that are least suitable for food production, it is actually possible to achieve higher agricultural yields," explained Cherubini.
The researchers have used European satellite data to map cultivated areas used for food production (cereals and vegetables) across Europe. This includes areas with steep terrain, areas that produce low yields, or where cultivated plots of land are small and scattered. Grassland used for the production of animal feed has not been included.
The study, published in the journal Nature Communications , shows that Europe has 24 million hectares of this type of agricultural land.
These are areas that are low in productivity and expensive to farm. In addition, they are often in direct conflict with efforts to protect biodiversity. Approximately 14 per cent of agricultural operations in Europe, including Norway, takes place in areas considered to be less favourable.
Improving the carbon balance
Of these areas, about two-thirds are at risk of becoming less fertile due to soil degradation, and half of them are located in areas with important or threatened habitats and species.
By allowing natural vegetation to regrow in these 'sub-optimal' areas, while also optimizing production on better agricultural land, the study shows that emissions from agriculture can be reduced by up to 40 per cent. Pressure on biodiversity can be reduced by 20 per cent, while food production is maintained.
"Allowing natural vegetation to return to areas with poor crop yields benefits the carbon balance and increases biodiversity," added Cherubini.
The production lost by allowing this to happen can be made up for by focusing on more intensive cultivation in the best agricultural areas. At the same time, so-called extensification of agriculture can be introduced in areas where plots of land are small and scattered. Extensification involves using less fertilizer, pesticides and labour, while at the same time introducing more natural growth, such as trees.
"When we add up all the numbers, we see that it is possible to reduce climate emissions, increase biodiversity and at the same time maintain food production levels.
By allowing trees and natural vegetation to repopulate the cultivated areas that are least suitable for food production, it is actually possible to achieve higher agricultural yields. The trees' roots help retain nutrients in the soil. Erosion is reduced, and the carbon content of the soil is increased," explained Cherubini.
Requires collaboration
Research shows that crop yields can be increased by between 10 and 20 per cent through this kind of extensive farming. However, this requires changing the methods used and producing varieties of crops that yield the most calories per square metre.
In Europe, this means growing more maize, wheat and barley. However, the researchers also recommend focusing on the most suitable crops locally, meaning those already grown in the area, based on local knowledge and intended for a local market.
"When we add up all the numbers, we see that it is possible to reduce climate emissions, increase biodiversity and at the same time maintain food production. But it requires collaboration among the countries of Europe," added the researcher.
In the bigger picture, this means reducing production in steep mountain areas in Southern and Eastern Europe while improving and changing the production methods in more suitable areas.
Norway ranks high on the list when it comes to the proportion of land with poor productivity. One-third of Norway's arable land accounts for only 20 per cent of the country's crop yields.
However, Professor Gunnar Austrheim at the NTNU University Museum refers to Norway as an 'exceptional case' in this context.
"In Norway, one-fifth of the agricultural land is not very productive. But we have very little arable land overall, since two-thirds of the agricultural area is used to produce grass. As a result, we are not very significant in the European context."
Benefits of natural regrowth
He says the study should be seen as a feasibility study and points out that measures have already been initiated in Norway to restore natural environments, such as wetlands, moorlands and forests.
"Restructuring agriculture in this way might be seen as controversial. But it is important to remember that some areas of land have already been taken out of agricultural production. So, it is good to know that this also has value. More trees and wetlands increase carbon storage and also help preserve biodiversity."
Austrheim emphasizes that for many countries, including Norway, there may be social and cultural reasons to continue farming in low-productivity areas, even though these areas are expensive to manage and often subsidized.
"So, we are not saying that the whole of Norway should be left to grow wild, but the study shows that there is untapped potential," said Austrheim.
He reminds us of Norway's commitments under the UN Biodiversity Agreement from 2022, which also involve making agriculture more environmentally friendly. Among other things, the surplus of nutrients in agriculture must be halved.
"We must also halve the use of pesticides and restore 30 per cent of our natural areas. So we also need to do these things, albeit on a smaller scale. This study shows how the reallocation of land makes it possible to achieve important goals for agriculture," concluded Austrheim.
Source: Ting Hua, Xiangping Hu, Gunnar Austrheim, James D. M. Speed, Bob van Oort and Francesco Cherubini: Reconciling crop production, climate action and nature conservation in Europe by agricultural intensification and extensification | Nature Communications
