

Article
War, Agriculture, and Climate: The Limits of Our Food System
War, Agriculture, and Climate: The Limits of Our Food System
The war currently raging in Ukraine has served as a stark reminder of our dependence on energy and the need to prioritize energy conservation above all else, as we described in the article Reducing energy consumption: the best way to cut ties with Russian oil and gas in record time (read the article).
This war also highlights the current limitations of our European and French food systems from an energy and climate perspective. We will outline these limits using the example of three agricultural sectors: tomatoes, poultry, and field crops.
1. Tomato Production or Dependence on Natural Gas
Of the 6 million metric tons of vegetables produced in France (the third-largest producer in Europe[1]), tomatoes rank first with 643,000 metric tons produced in 2020.
For this leading crop, which is very popular among the French, Brittany is France's top-producing region, accounting for 25% of the total volume, followed by the PACA region with 23%[2]. However, tomato production—particularly in western France—is now carried out almost exclusively in heated greenhouses, most of which are heated with natural gas (the CTIFL[3] (estimated in 2016 that natural gas accounted for 77% of the energy used to heat tomatoes in France).

When you consider that a heated greenhouse used for growing tomatoes consumes an average of 300 kWh/m² per year[4], whereas a home with an E energy efficiency rating consumes[5] 240 kWh/m², which illustrates the very high energy dependence of this production. This energy consumption is reflected in the carbon footprint: a tomato heated with natural gas emits 1.7 kgCO2e/kg, compared to 0.2 kgCO2e/kg for an unheated tomato—a factor of 11[6].

Beyond the carbon cost, this war in Ukraine is also exacerbating the issue of energy costs for producers. Indeed, with gas prices now at 200 euros per MWh—up from 30 euros before the war—some tomato growers in Brittany and elsewhere are unable to pay their bills and are therefore forced to turn off their heating, risking lower yields and reduced production.
This crisis illustrates how the growing scarcity of fossil fuels—whether due to a geopolitical crisis or the climate transition—exposes certain sectors of French agriculture to major business risks.
- The issue of energy transfer certainly warrants further study: this is the case, for example, with mixed-farming operations that will have anaerobic digestion units derived from their livestock operations, which will enable them to heat greenhouses using the residual (or “waste”) heat from the biomethane production process.
- Greenhouse growers and vegetable farmers are also already working to reduce energy consumption in greenhouses through measures such as insulating the piping system or using greenhouse walls with better insulation.
- Nevertheless, in a low-carbon world where energy is a scarce and expensive resource, we need to consider how to grow tomatoes in France using as little energy as possible. This can and must involve developing other French production areas outside the Greater West region—still in greenhouses, but in locations where tomatoes can grow without the need for heating.
2. Chicken production or dependence on imported protein
Poultry is currently the second-most-produced meat in France after pork, with total production amounting to approximately 1.7 million metric tons of carcass-equivalent[8] (or 28 kg per capita) compared with 2.3 million metric tons of carcass-equivalent pork (or 31 kg per capita).[9]
While chicken production may appear to have a low carbon footprint per kilogram consumed (~1.9 kgCO2e/kg for a conventionally raised chicken compared to ~2.5 kgCO2e/kg for a conventionally raised pig[10], there is still significant room for improvement, particularly when it comes to how we feed our poultry farms. In fact, broiler chickens are now fed almost exclusively on complete feed (FAB, not produced on the farm), two-thirds of which consists of grains (corn, followed by soft wheat), one-quarter consists of oilseed meal (mainly soybean and sunflower), and 12% consists of oil- and protein-rich grains.


However, if we look at the origin of these foods (see chart above), We realize that the meal our chickens eat comes from France only to a very limited extent in the case of sunflower meal (31%) and not at all in the case of soybean meal (1%).[11].
- Sunflower meal very often comes from the Black Sea region, specifically Ukraine, which is the world's leading producer of sunflowers[12]. Given the current context, it quickly becomes clear what the systemic risk of such dependence is.
- Soybean meal, on the other hand, comes mainly from Brazil[13], which also poses an economic risk in the event of major disruptions in that part of the world.
From a carbon perspective, the carbon footprint of sunflower crops imported from Ukraine and elsewhere may be similar to that of French crops. Nevertheless, as with any imported crop, it is much more difficult to implement emission-reduction measures in the field when it is located abroad, and thus to guarantee a 40% reduction.[14] emissions from crops, as required by France’s SNBC (National Low-Carbon Strategy). Finally, The link between imported crops and emissions is significant for soybeans, since they are often grown on recently deforested land[15], thereby increasing the carbon footprint of the livestock operation under study. Thus, French soybean meal emits approximately 370 gCO2e/kg, while Brazilian soybean meal linked to deforestation emits 1,670 gCO2e/kg[16], which is more than four times as much.
From the producer’s perspective, as with tomatoes, the issue of price is also a major concern because the price of these imported raw materials is highly volatile due to political and climatic uncertainties on a global scale. Due to the war in Ukraine and the expected drop in Ukrainian production, the price of sunflower meal is currently close to 430 € per metric ton, delivered to port.[17] compared to less than 280 € a year ago, which is a 1.5-fold increase in price.
Of course, this situation is not hopeless. Just as we need to question where certain fruits—such as tomatoes—are produced, we must also ask how France can reduce its dependence on imported protein.
It therefore seems essential, regardless of the type of animal production, to support the plant-based protein sector in order to improve France’s protein self-sufficiency. This involves, in particular, reviving the cultivation of protein crops such as peas and fava beans.

In 1994, as shown in the graph above[18], production of these two crops for animal feed totaled more than 2 million metric tons, whereas today it amounts to less than 300,000 metric tons[19]. Increasing the share of protein crops produced in France in animal feed—including for poultry—is necessary to reduce our dependence on food, as well as our reliance on fossil fuels and carbon.
To do this, we need to look beyond mere ideals and understand the obstacles to growing these crops so that we can overcome them[20]. This involves:
- improving these crops’ resistance to water stress, pests (aphids), and diseases (viral infections) in order, at the very least, to stabilize yields and avoid very low harvest yields such as those seen in the 2020 growing season;
- greater financial recognition of these crops, given their environmental and carbon benefits;
- better structuring of the sector by stakeholders working with farmers (chambers of agriculture, agricultural advisors, cooperatives, technical institutes).
3. Field Crops and Dependence on Nitrogen Fertilizers
After tomatoes and chickens, it’s time to talk about grains, since they account for 35% of the agricultural land[21] and that France is Europe's leading producer. The main grains produced in France are, first and foremost, wheat, with 29.2 million metric tons produced, followed by corn with 12 million metric tons, and finally barley with 10 million metric tons[22].
Like all plants, cereals require 16 essential nutrients for their growth cycle, particularly the well-known trio of N (nitrogen), P (phosphorus), and K (potassium). Without adequate nitrogen inputs, yields can be reduced, and the protein content of grains can also decline. While phosphorus and potash consumption has fallen sharply in France over the past 20 years (a 70% reduction), nitrogen fertilizers remain important, as France imported 2.1 million metric tons of nitrogen fertilizers during the 2019–2020 growing season[23]. And today, the vast majority of these volumes are dedicated to field crops.
Today, in France, These nitrogen fertilizers are primarily in the form of ammonium nitrate, which is manufactured from ammonia—a substance produced from fossil fuels such as natural gas and coal. As with oilseed meal, France does not meet all of its nitrogen needs but only one-third of them; the rest is supplied by European Union countries (about 40% via Belgium, Germany, and the Netherlands) and a quarter by countries such as Egypt and Russia[24].
Once again, Due to a reliance on fossil fuels, the carbon footprint of nitrogen fertilizer production is significant: Ammonium nitrate emits 3,770 kgCO2e per metric ton of nitrogen, while urea emits more than 4,200 kgCO2e per metric ton. By comparison, virgin plastic derived from petroleum emits approximately 2,400 kgCO2e per metric ton produced[25]. Furthermore, these fertilizers also emit significant amounts of greenhouse gases during the application phase (when they are spread), because nitrogen (whether of mineral [chemical] or plant origin) can volatilize in the form of nitrous oxide, which is a powerful greenhouse gas (265 times more potent than carbon dioxide[26]). Thus, fertilizers as a whole account for approximately 45 million metric tons of CO2 equivalent[27], or nearly 40% of emissions from French agriculture, three-quarters of which are linked to their use.

The economic risk is also considerable, since two-thirds of nitrogen fertilizer production comes from foreign countries, which may be our neighbors but are ultimately highly dependent on other countries for energy—such as Germany—or countries that are geographically farther away, like Russia, with the geopolitical risks we are all aware of today. Thus, The price of 33.5% ammonium nitrate has skyrocketed due to the war in Ukraine and the halt in Russian exports: it now stands at over 1,000 € per metric ton, compared to less than 350 € a year ago[29], which is three times the original price.
Just like tomatoes or crab cakes, it is essential to approach nitrogen management with two constraints in mind: self-sufficiency in production, as well as energy and carbon efficiency, as these two concepts are closely linked. While it is always possible to further optimize nitrogen inputs in field crops (e.g., through precision agriculture), it is nevertheless necessary to rethink our agricultural practices and cropping strategies in order to reconcile economic and climate challenges.
- Bringing back mixed farming in France is part of the solution, in the sense that organic fertilizers from livestock operations can help nourish the soil, thereby ensuring a circular system within the farm. In fact, the number of farms practicing mixed cropping and livestock production has decreased by more than 30% over the past 15 years, while the number of farmers growing only grains and oilseeds and protein crops has increased by about a quarter.[30] ;
- Crop diversification is also essential for reducing nitrogen-related emissions and our economic dependence. Specifically, this involves introducing legumes (soybeans, peas, fava beans, alfalfa) into the crop rotation system, as they have the ability to fix nitrogen from the air, unlike other plants. These same legumes can then be used to feed livestock and improve our protein self-sufficiency. Expanding soybean cultivation in France, in addition to peas and field beans, is thus part of the solution, and a European study[31] A study published in April 2022 showed that Europe could be entirely self-sufficient if 11% of Europe’s farmland were devoted to soybeans. The goal of doubling the area of French farmland dedicated to plant proteins, as part of the legume plan, can thus help reduce our dependence on imported mineral fertilizers.
- Finally, The shift toward diets higher in plant-based proteins is a key factor in reducing our consumption of and emissions from nitrogen fertilizers, as IDDRI explained in its report “An Agroecological Europe by 2050”. However, the links between changes in dietary patterns and nitrogen imports and exports in France will be the subject of a future analysis by Carbone 4.
Conclusion
These three sectors are just a few examples of the many challenges facing French agriculture today. This also shows that tackling the climate issue head-on will undoubtedly help resolve other major challenges, such as the economic viability of farms, dependence on foreign countries, and so on.
These structural changes—whether for tomato, poultry, or grain producers—nevertheless require substantial human and financial support so that the transition can take place quickly enough and on a large scale. This support depends, of course, on government authorities, but also on stakeholders throughout the value chain—such as cooperatives, manufacturers, and retailers—in order to drive this shift in the food system.
1.
Graph’Agri 2021. Agreste.
2.
Figures and maps from the France AgriMer website.
3.
From the study titled “Trends in the Number of Heated Greenhouses for Tomatoes and Cucumbers.” CTIFL. 2016
4.
Ex Post Evaluation of Funding Programs for Certain Modernization Expenses in the Vegetable and Horticultural Greenhouse Sector. FranceAgriMer. 2013.
Article: Did You Know? – Production in Heated Greenhouses. ADEME website.
5.
"Agir pour la transition" website. ADEME.
6.
Agribalyse Values v3.1. Values used: “Conventional tomatoes, newly built greenhouse, natural gas, no drainage recycling, on the farm” and “Conventional tomato, medium-sized basket, grown in an unheated greenhouse, national average, sold at the farm”
8.
Carcass-equivalent metric ton: a unit used to compare the weight of carcasses, processed products, and canned goods.
9.
Graph’Agri 2021. Agreste.
11.
Raw Material Flows within the “Livestock Feeding” System, France, 2015. Part Two of the Project. GIS Avenir Élevages. August 2020.
12.
Data from the FAO (retrieved from FaoStat).
13.
Data from the FAO (retrieved from FaoStat).
15.
"Recently" refers to the past 30 years
16.
EcoAlim v7. Values used: “Soybean meal, Brazil, associated with deforestation, crushed in Brazil, delivered to port (Brest)” and “Partially de-oiled soybean meal, France, hulling + ACP, France, ex-factory (processing plant)”
17.
Sunflower meal prices obtained from web-agri. Dates used: March 5, 2021, and March 17, 2022.
18.
Statistics on Oilseeds and Protein-Rich Crops. 2021 Edition. Terres Univia.
19.
Raw Material Flows within the “Livestock Feeding” System, France, 2015. Part Two of the Project. GIS Avenir Élevages. August 2020.
20.
History and Global Challenges of Protein Self-Sufficiency. Sylvain Pellerin. INRAE. 2020.
21.
Graph’Agri 2021. Agreste.
22.
Graph’Agri 2021. Agreste.
23.
Graph’Agri 2021. Agreste.
24.
Data from UNIFA and the following website, https://fertilisation-edu.fr/production-ressources/engrais-azotes.html
25.
Figures from ADEME's Carbon Database
26.
IPCC Fifth Assessment Report (2013)
27.
Energy and Carbon Content of Household Diets in France. Final Report. 2019.
29.
Nitrogen fertilizer prices obtained from web-agri. Values used for 33.5% ammonium nitrate: April 2, 2021, and April 1, 2022.
30.
Tables on the French Economy. 2020 Edition. INSEE.
31.
Data-driven projections suggest significant opportunities to improve Europe’s soybean self-sufficiency in the face of climate change. Guilpart, N., Iizumi, T., & Makowski, D. *Nature Food*. 2022.
7.
Agribalyse Values v3.1. Values used: “Conventional tomatoes, newly built greenhouse, natural gas, no drainage recycling, on the farm” and “Conventional tomato, medium-sized basket, grown in an unheated greenhouse, national average, sold at the farm”
10.
Agribalyse v3.1. Values used: “Chicken, conventional, farm-gate” and “Pork, conventional average, national, farm-gate”
28.
Energy and Carbon Content of Household Diets in France. Final Report. 2019.


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