The global concentration of methane in the atmosphere increased more than ever in 2021. Agriculture is considered to be one of the biggest causes. Methane - the second most important greenhouse gas after carbon dioxide (CO2) - is emitted primarily in cattle breeding. For Ulrich Mück, agricultural engineer and consultant for sustainable agriculture, a one-sided view: "Cattle have been excreting methane for 30 million years," he emphasizes in ntv's "Climate Laboratory" - without new sources having been added, as he says . In addition, the positive characteristics of ruminants are ignored: "Cattle play an extremely important role in biodiversity and carbon sequestration," says the livestock expert. Therefore, sustainably managed grassland has a carbon content that is up to five times higher than an average field - from which vegetarians and vegans feed. Mück's tip? Others are best advised to eat their portion of beef - while avoiding pork and poultry.
ntv.de: Are vegetarians more climate-friendly than people who eat meat?
Ulrich Mück: That's a difficult question because it focuses so much on the subject of meat and beef. You shouldn't actually do it that way in a "life context earth". You have to look at the big picture in order to then say: What role do cattle actually play for the climate, but also beyond that?
But people are always looking for the simple solution. And according to leading science, this is: If people want to eat more climate-friendly, it is best to avoid beef as much as possible. Would you disagree?
In terms of beef, yes. We need more people eating beef. This is the only way we can preserve the climate and, in particular, bind the carbon where it belongs: in the grassland of the earth.
Not enough people eat beef?
And.
Many are now probably questioning what they have heard and learned over the past 10 or 20 years. Please explain.
If we look at the agricultural areas of the earth that people feed, we have at least two-thirds grassland and one-third arable land. Vegans have to feed themselves from the field, because the grassland is converted into meat and milk by herbivores and especially cattle. Grassland provides the majority of human nutrition. In this respect it must be said that people on earth could not be fed without meat eaters.
So vegans are bad for the environment?
You can't say that either. Basically, everyone is free in their diet. But with regard to the climate, we also need to take a look at the life context on earth in order to get a basic orientation on nutrition. It can take the form of someone in the family eating little or no meat and saying: Eat a double portion so that we can implement sustainable agriculture on earth.
A new study from the University of Oxford looked at which foods are climate-friendly and how. As is so often the case, meat products, especially beef products, are among the worst performers. How then can beef be so good for the climate?
The problem with the Oxford study is that product-related average values are determined. These assessments of individual foods have incredibly wide ranges. A single product can be both enormously climate-damaging and climate-positive - depending on how much fossil energy is used in production, collection, processing, transport and packaging. In this respect, mean values that are published in many studies are actually only correct for a single product. But this approach cannot be used to assess the basket of food that the earth offers as food.
So the problem is the viewing, not the cattle?
We have to look at climate-friendly or climate-damaging food in terms of area: What areas are there on earth? What are they good for? Food can only be sustainable if people eat along these surfaces. An individual can then of course decide for themselves, I eat vegetarian. It just has to be very clear: it doesn't work for everyone. We need many eaters of beef on earth. An important point that comes with cattle: methane gas plays a major role. The climate impact of methane on cattle has been misjudged for many years, i.e. overestimated.
Why too strong? We all know that methane is one of the most harmful greenhouse gases. It doesn't stay in the atmosphere quite as long as CO2, but it has a strong short-term effect on global warming.
But as long as a constant level of methane is excreted, which is largely degraded within a decade, it loses its temperature-increasing climate damage. At least, as long as there are no new sources, which is not the case with cattle. They have been excreting methane through their digestive system for 30 million years.
But due to factory farming, there are many more cattle on earth today.
Not in Germany and not in Bavaria. For Bavaria, thanks to a large cattle census in the Bavarian Kingdom in 1873, I can even prove that there were 22.7 percent more cows then than there are today.
But the number of cattle has already increased worldwide, hasn't it?
Possibly. In concrete terms, I can understand that the number of cows in Bavaria and Germany has not increased during the man-made climate change - that is the period since about 1880.
But when it comes to climate change, we have to look at the whole world. It doesn't help if there are fewer cows in one country and more in 100 others.
The fundamental question is: Why are cattle involved in man-made climate change at all? There are also other natural methane producers such as leaf-cutter ants, termites or wild ruminants.
Because we keep cattle as livestock, but not termites.
But then we also have to look at other aspects, such as food security, which are not taken into account. Cattle play a tremendously important role in biodiversity and carbon sequestration. For 30 million years, by browsing the grassland, they have repeatedly stimulated the native plants to sprout new roots, while the old ones have enriched the carbon in the soil. Therefore, grassland has a carbon content 1.2 to 5 times higher than an average field.
But that only applies to cattle that are allowed to roam around outside in the pasture and not to those that are standing somewhere in one and the same place in a huge stable.
If cattle are fed grassland, they are climate-friendly and climate-positive. If, as is done in many conventional animal husbandries, they receive a large proportion of their rations from concentrated feed, then no. But grassland and cattle are a natural, wonderful pairing. In this form, cattle are also digestive wonders, capable of converting low-grade, unavailable biomass into food.
Let's take Brazil as an extreme example. Huge areas are cleared there so that cattle can graze. How do you classify this system?
Such feedlots, as known from Mexico or the USA, should not be supported and such cattle should not be eaten. But we are in Germany and have beef from organic farming and grass-fed beef. This is clearly a climate-friendly diet that should be promoted.
Okay, ideally no beef from Brazil, Mexico or the USA, only organic farming from Germany. And in what quantities? You said earlier that there needs to be more people eating beef.
Meat consumption in Germany is enormous and must be reduced. But 83 percent of the slaughter weight is pork and chicken, only 15 percent beef. So please reduce meat in animals that are actually systemic food wasters. Because their meat and their eggs result from the fact that an enormous amount of food is fed. For each ration it is about 80 percent. That's wasteful.
So the advantage of cattle and cows is that they make usable food out of practically nothing or out of things that the human body cannot process. Pigs and chickens, on the other hand, eat the same as humans.
Yes, they are food competitors. The beef - at least potentially - doesn't. It can make 100 percent food in the form of meat and milk from 100 percent grass. There's also a scientific term for this: food conversion efficiency. The usual rations and agricultural animal species were juxtaposed and comparisons were made as to how efficiently edible food was produced from non-food items such as grass or waste from the milling industry. If cattle are fed about 10 percent food and 90 percent grass and pigs and poultry 50/50 with food and feed that comes from the second stage of utilization of the food - post-meal from the mill, for example - it shows that cattle get a three - Have up to four times the ability to create food from non-food.
In addition, we absolutely need cows to conserve carbon in the grassland and to store more carbon. There is about five times more carbon in the earth's permanent grassland than in all the fields in the world.
And how could it happen that cows and cattle of all things were declared climate killers? Also in many scientific studies? Are you missing the lobby?
Some lobbying may play a role. However, the assessment of climate change according to the IPCC, i.e. the Intergovernmental Panel on Climate Change, is very unsuitable for decoding overarching aspects. It is simply looked at national balance sheets. Influences such as feeding imported feed to pigs and chickens are left out, and with them the CO2 load that has arisen abroad.
But the people at the IPCC are not stupid and are certainly open to your arguments. You should be able to understand that and then adjust the accounting.
For millions of years, including in human cultural history, cattle have had a positive effect in so many areas. This cannot be understood from the sectoral perspective of a climate researcher or a physicist. But for two decades, there has only been a focus on the climate for cattle, nothing else: the preservation of grassland? The conservation of carbon? But cattle are leading animals - also in the biodiversification of diverse grassland landscapes over the cow dung. It is a refreshment for many insects.
Does that have negative consequences? You say quite openly that the trend towards veganism and vegetarianism is going in the wrong direction.
I don't see this trend positively. I would like to persuade these people to say to others: I don't like beef, but please eat my share. That would be good for the earth's basic shopping basket, which offers two-thirds permanent grassland and one-third arable land.
Does the ideal diet then look like two-thirds of your diet comes from cows or goats and one-third from vegetables, grains and fruit?
no We don't need herbivores, so purely vegan eaters. We also don't need carnivores that eat only meat, nor omnivores that eat both. Instead, we need a fourth dimension of the nourisher, namely the locavore. Jessica Prentice, a nutrition activist from the USA, coined this term a few decades ago. This describes a person who feeds mainly on what grows in his environment.
Which brings us back to the regional approach.
Exactly. If I live in a region where there is a lot of grassland, my diet should consist primarily of meat and milk from grassland animals. In regions with less grassland, the percentage may be lower. That would also require much less transport energy.
But of course that assumes that countries like Brazil also convert their cattle farming to a sustainable one.
That would mean a completely different orientation for many countries. The amazing thing is that the concept of food sovereignty has been central to development aid for decades: every society should be able to produce the majority of its own food. We should also apply this to ourselves and say: First, we eat the food that grows on our local land. For the world at large, that would be a very important policy approach.
Clara Pfeffer and Christian Herrmann spoke to Ulrich Mück. The conversation has been shortened and smoothed for better understanding.
