18. July 2019
Potatoes to save the planet
Species protection is one of the greatest challenges we are facing
By Peter Breunig*
Maintaining and increasing crop yields is not only a desire of agriculture, but also makes an important contribution to species and climate protection, i.e. for all of us.
At the beginning of the year, over 18 percent of the Bavarian population signed the petition for a referendum “Save the bees!” – more people voted than at any other referendum in the history of Bavaria. The explosive nature of the issue of species conservation was then confirmed once again in May by a current inventory of the World Biodiversity Council (IPBES)1: Of the estimated eight million animal and plant species, about one million, according to the researchers, are threatened by extinction and the extinction rate continues to increase. Apart from climate protection, species protection is one of the greatest challenges we and our plant are facing.
Due to the clear success, the bill of the petition for a referendum was adopted without changes by the Bavarian state government and even expanded. The final law includes, among other things, specifications and measures for the management of grassland, for the promotion of flowering strips and organic farming, as well as for a significant reduction in chemical plant protection2. As a result, these measures will probably promote biodiversity, but at the same time reduce the harvest of agricultural products in Bavaria: Where there is a flowering strip, no cereals grow; in organic farming farmers harvest on average 30 percent less3 and with significant restrictions in chemical crop protection yields will tend to decline (unless we develop resistant varieties through e.g. CRISPR/Cas4).
The fact that we give up harvest yield to make environmental services possible is hardly ever addressed as a possible conflict outside agriculture. It seems that many people think primarily of benefits for farmers and agribusiness companies when it comes to stabilising or increasing crop yields. In some cases, the goal of increasing yields even has a quasi “unethical” image. But why should it be any different if the value of high yields is hardly present in society? Even in the drought year of 2018, with significant yield losses in Europe, supermarkets continued to be lavishly filled with cheap food. The international trade in agricultural goods never leaves the shelves empty and leads to the fact that many people no longer see a direct connection between agricultural conditions and the supply of food.
Maintaining or increasing crop yields is not only a desire of agriculture, but also makes an important contribution to species and climate protection, i.e. for all of us. I would like to illustrate this connection in the following.
Space is scarce – and will become even scarcer
About half of the habitable area of our planet is currently used for agriculture. Of this, about one third is arable land and permanent crops (e.g. fruit trees) and about two thirds are used as grazing land for animals5. Despite all the ecological consequences, there has still been an expansion of arable land worldwide in recent years, especially in developing countries. On the other hand, soil erosion, devastation and, in particular, construction measures in developed countries mean that many areas are lost to agriculture. Due to the global population growth from currently 7.7 billion people to approx. 9.7 billion in 2050, per capita arable land is expected to fall by 15 percent in the next 30 years, despite further deforestation and conversion into arable land6.
In Germany, we already have a shortage of land: the report on “Flächenbelegung von Ernährungsgütern” (“Occupancy of Food Land”) by the Federal Statistical Office7 calculated for 2016 that the German population needs a total of 18.3 million hectares of agriculturally used land at home and abroad, of which 11.2 million hectares alone for animal feed (meat, milk, eggs). Germany currently has 16.7 million ha of agricultural land at its disposal, i.e. we need 1.6 million ha more for our food than we have and must compensate for this by net imports of agricultural goods. This corresponds to almost the entire agricultural area of the Netherlands.
Agricultural use of an area always means that we can no longer use the ecological advantages of the natural vegetation
At the end of last year, a study on land use and its impact on climate protection was published in the scientific magazine “Nature “8. The results presented in the study are based on the insight that the natural vegetation of an area can store more and more CO2 in the form of organic matter in the soil and above-ground biomass than the same area when used for agriculture. If we want to assess the true consequences of agricultural land use on the climate, we have to assign the renunciation of CO2 storage capacity to the natural vegetation of the agricultural land. This means that we must not simply consider which direct emissions are caused by agricultural land use (fuel, fertiliser, etc.), but must also take into account the storage capacity of the original vegetation lost as a result of agricultural use.
These services (here the storage of CO2), which are abandoned by a decision, are called “opportunity costs”. If these “CO2 opportunity costs” in agriculture are taken into account, the significance of land use for climate protection changes fundamentally: the study9 comes to the conclusion that our typical Northern European diet is responsible for approx. 9 t CO2 emissions per person and year. This corresponds to all assumed per-capita emissions including mobility, heating, electricity etc. together!
So far, the ecological consequences of the use of land have been clearly underestimated, particularly in terms of greenhouse gas emissions and biodiversity. The ecological effects of a conversion from natural vegetation to agricultural use are often many times higher than between different agricultural cultivation systems (e.g. from conventional to ecological).
Depending on the diet, different amounts of land are needed for the production of food. Foods of animal origin in particular have a significantly higher area requirement per calorie or gram of protein, as there are losses in the conversion of feed into meat, milk or eggs10. This means that the less animal food we consume; the less land we need. On the other hand, ruminants such as cattle or sheep can also use grassland that we humans cannot use directly. The above-mentioned Nature study comes to the conclusion that a vegan diet produces less than a quarter of the CO2 emissions compared to a typical omnivorous diet due to the smaller area required – this corresponds to savings of more than 6t CO2 per person and year (≙ approx. 60,000 km with a small petrol car).
Another factor that influences the space required for our food is the spoilage and waste of food along the value chain. Currently, about a quarter of all calories produced spoil in the fields, warehouses, supermarket shelves or refrigerators11. Every reduction in these losses reduces the need for space.
On the production side, each extensification leads to a higher space requirement: If 30 percent less is harvested in organic farming12 , 43 percent more land13 is needed to produce the same amount of food. If a strip of flowers is sown, the amount has to be produced on another area if the total production is not to decrease. Due to the CO2 opportunity costs of the higher area requirement, organic farming also comes off worse than a conventional cultivation system in terms of climate protection in the above-mentioned Nature study.
A study from “Nature Communications” from 2017 has investigated these interrelations between the demand and production sides with regard to land use in more detail14. One of the results was that it is possible to feed the world 100 percent with organic farming from the currently available arable land in 2050, despite the significantly lower yields. However, this strategy can only be implemented if the consumption of food of animal origin is massively restricted and no more feed is produced on arable land (i.e. animal husbandry will then only take place on grassland). Agricultural production and our consumption and nutrition patterns are therefore comparable to the two sides of a balance: the way we (can) farm depends on how we feed and vice versa (Martin also deals with the aspects of a progressive change in diet in his series15 on this blog).
This results in the following basic options, which we could also implement together in different combinations:
More organic farming (flowering strips, organic farming, etc.) at the expense of yield is possible, but these changes must be accompanied by a significant adjustment in demand.
If demand remains unchanged, ecological measures at the expense of yield lead to new land having to be gained elsewhere or production having to be intensified in order to compensate for the decline in yield. This can then lead to more CO2 being emitted and biodiversity being reduced at another location.
To return to the petition for a referendum in Bavaria: unfortunately, only the extensification of production was discussed here, but not a reduction in demand. This means that the well-intentioned measures could lead to the destruction of more biodiversity and more CO2 emissions. Unfortunately, there seems to be very little political interest in intervening seriously in food consumption: the fierce criticism and discussion regarding the Green party’s proposal for a “Veggieday” in 2013 have shown how little popular such approaches are.
If we cannot or do not want to drastically adapt and limit our diet globally, we must use technologies to decouple the links between demand and land consumption, yield levels and ecological consequences on the land used.
Up to now, the income of the population in most regions of the world (especially developing countries) has been accompanied by an increase in the consumption of animal food and thus in land requirements16. This means that the better off people are, the more land we need in many cases.
On the production side, the enormous growth in crop yields in many parts of the world has led to negative impacts on soil, water and biodiversity on agricultural land. However, due to the increased crop yields, relatively little land is needed to produce a corresponding amount of food.
Organic farming does indeed perform better in relation to the area used under many ecological criteria17 , but unfortunately only with significantly lower yields at the same time. As described above, this increases the land requirement by an average of 43 percent.
New technologies can provide a way out of both conflicts:
On the demand side, these include alternative proteins such as plant-based meat substitutes (Beyond Meat etc.) or in vitro meat18. These have the potential to reduce land use while retaining the same or similar sensory properties and nutrient content19. But digital tools20 and apps for networking participants in the value chain21 can also help to prevent the unnecessary throwing away of many foods and thus reduce the amount of space required.
On the production side, new technologies and cultivation systems can lead to a situation in which the relationship “the higher the yield, the higher the negative impact on the environment on the land” can be partially overturned: Artificial intelligence to detect weeds and crop plants allows savings of up to 90 percent on weed killers22. Varieties modified by genome editing are resistant to plant diseases and do not require chemicals23. High-precision and automatically controlled machines allow a variety of crops to be grown in a field without significant disadvantages in productivity. New cropping systems integrate biodiversity benefits through catch crops, underplanting and mixed crops.
These two options have been determining the discourse on global issues for many decades, especially on the subject of agriculture24: Do we have to limit our consumption, accept the limits of the planned and return to more naturalness, or should we use new technologies that overcome the limits and current challenges and enable new growth? In principle, this question also describes the core of the discussion between organic and conventional agriculture.
Will this discourse ever be brought to an end and lead to a consensus, to “the one agriculture”?
First and foremost, however, we would have to move the discussion away from the question of how we conduct agriculture and towards the question of what measurable ecological goals we actually want to achieve on agricultural land. On the basis of these goals, existing arable farming systems (such as organic or conventional agriculture) could be evaluated and perhaps new approaches between organic and conventional could be developed. Within the arable farming systems that achieve the measurable ecological objectives on the land used, those that deliver the higher crop yield would be assessed as “better”. This would minimise land requirements and the negative effects of land use.
Giving up crop yields for ecological measures without addressing the demand side is not a truly sustainable approach. Because the ecological impact of land use on our planet is too great for us to accept a drop in yield without thinking about it. Increasing crop yields within measurable ecological goals (whether in organic, conventional or agriculture “in between”) should move us all, because it is about nothing less than the future of our planet.
*This article has first been published at Progressive Agrarwende.
- Beispiel: 10 t/ha * 100 ha = 1.000 t => 1.000 t / 7 t/ha = 143 ha
- Siehe auch: https://progressive-agrarwende.org/ernaehrungswende-prolog/
- Beispiel: https://ovie.life/
- Beispiel: https://toogoodtogo.de/
- Charles C. Mann hat dies in seinem Buch „The Wizard and the Prophet“ wunderbar beschrieben