“We need greater recognition for agriculture”

Soil with a high humus content is the key for healthy plants and a high yield. But it’s also an ideal carbon pool and contributes to climate protection. Anyone who builds up humus should be financially rewarded in the opinion of Rolf Sommer of the WWF. He’s a soils expert and knows about the challenges for the agricultural industry –and what farmers will need to change in the fields in the future.

Dr. Sommer, climate change presents major challenges for agriculture and is already threatening livelihoods in the farming sector. How can this trend be stopped?

We had two dry summers and it looks like it will also be very dry again this year. Climate change and the climate crisis are already making their presence clearly felt in this way. We all need to contain this crisis. We must meet the Paris Climate Agreement and remain below its agreed 1.5 degree goal. We as a society must see what we need to do to achieve that. If we do nothing, agriculture will be one of the biggest losers in this crisis. At present, it is still part of the problem, but it can and must also be part of the solution. The fact is that it faces several challenges. To meet them, agriculture must be in a more resilient position. We must change course! Specifically, the choice of crops and crop sequence is becoming increasingly important. Farmers must diversify more.

It’s not only climate change that’s increasing the pressure on agriculture. By 2050, there will be ten billion people living on Earth. That puts the focus on the issue of nutrition. Where should all the food come from?

Feeding almost ten billion people in 2050 is a mind-blowing challenge. But I’m confident that we’ll be able to do it. And I’m especially confident that the countries of the global south will be able to feed themselves on their own. I worked myself for a number of years in Kenya, and government there is doing all it can to stabilize food security in the country. However, what we do need in these countries is a sustainable intensification of agriculture.

Can Germany help in that?

We must support them – with know-how and financial resources. Tropical countries do, however, need a completely different kind of agriculture. Applying our crop cultivation one-to-one doesn’t make sense. What we don’t need are subsidized, cheap food that floods the markets in these countries, since that destroys regional markets and regional production. These countries must triple their yields of one and a half tons per hectare. And they will only achieve that with better soil management and better management of the crops.

With a view to the necessary increase in production in the coming decades: What does that mean for the work of the farmers?

In Germany, we have already an impressive level of supply. Farmers are doing a lot right. But what could still be improved? I think that farmers are very interested in learning more about how crop rotations can be made more diverse, in other words, more crops and fewer monocultures planted. There’s still major potential here! What’s also vital is managing and building up humus. This increases the soil fertility and resilience. That has many advantages. Fertile soil retains more water and can then better provide the plants with water during dry periods.

Humus stores enormous amounts of carbon. That is active climate protection! And farmers must be rewarded for this!

As an agricultural scientist you look very closely at soils. How can they be sustainably improved?

It’s essentially about these questions: How much crop residue do I leave in the field? How much compost do I use? How much manure is spread in the field? How much root biomass remains in the soil as organic matter? That means all organic matter that is turned into humus through decomposition processes. Sustainable soil fertility is directly connected with the humus. Humus ensures that plants are better able to absorb nutrients. It ensures that the soil can retain much more water.

But what does that mean specifically for the work of the farmers?

One example would be expanding crop rotations in Germany, for instance. We have the problem that the crop rotations are too close together, in other words, two or three crops in the rotation. We must diversify here and introduce other parts into the crop rotation. Clover grass, a mixture of clover and grass, works well. It’s known for sustainably increasing the humus content in the soil. But clover grass isn’t economically viable for every farmer. The political course therefore needs to be set so that it also makes economic sense for farmers. Clover grass is very useful in ecological terms.

WWF expert Dr. Rolf Sommer advocates a more sustainable agriculture. He sees great potential in the development of humus to bind carbon and thus counteract climate change.

WWF expert Dr. Rolf Sommer advocates a more sustainable agriculture. He sees great potential in the development of humus to bind carbon and thus counteract climate change.

What do you think of a financial reward for farmers with soil that’s especially rich in humus?

I’m all in favor of farmers being remunerated if they use their agricultural measures to ensure that this happens. Why? Humus stores huge amounts of carbon, extracting it from the atmosphere. That’s active climate protection! And farmers must be remunerated for that. After all, every other sector is remunerated when it does something for the climate. Why not the farmers as well? We must therefore ensure that the government sets a course for that to happen. The WWF takes the view that direct payments via the EU subsidies for agriculture should be conditional upon whether or not farmers build up humus.

So-called humus certificates are an opportunity for the climate. Where do you see other need for action for climate-friendly agriculture?

Soil compaction is an urgent problem. There is a tendency with compacted soils for water to accumulate on the ground in heavy precipitation and not be able to seep away. This accumulated water runs off and causes erosion. That means soil is lost when the rainwater is washed away. To prevent that, making a very good choice of the time, for one thing, is necessary: When do I drive over the field – especially when I’m using heavy machinery? I can also try, through reduced, more conservation-friendly agriculture, so-called conservation soil cultivation, to avoid and also reduce compaction in the long term. Less plowing and harrowing would be an option. Or dispensing with them completely.

Farmers must be paid to produce good food without harming the environment.

With regard to soil health, fertilization is the target of criticism. What difficulties and responsibility do you see?

The problem areas are nitrogen and phosphate, two nutrients that plants need. In the case of nitrogen, we have the major problem, however, that we currently practice a kind of agriculture in which far more nitrogen is spread across the field than the plants actually need. This is referred to as nitrogen surplus. What happens to the excess nitrogen? It ends up in the groundwater as nitrate or is lost as nitrous oxide, a gas that’s very harmful to the climate. These problem areas urgently need to be addressed.

How can nitrogen surplus be avoided?

We must move through plant breeding to varieties and cultivation systems that allow us to significantly increase the absorption of the fertilizer. We are currently in the situation in which at least fifty percent of the nitrogen that has been spread is not absorbed by the plant. That has to change, we have to adopt completely new approaches. That's a challenge for plant breeding.

Alongside a higher absorption capacity, what plant properties should the breeding research?

The climate crisis and future food security pose huge challenges for plant breeding. Even if climate change only comes in a reduced form, as now forecast, we will have a number of problems to deal with. Conventional plant breeding – in other words, breeding resistance to diseases and pests – still remains. It has to. It faces the task of the century. Given the climate crisis and food security I would even say: Breeding toward drought tolerant varieties and varieties that are also better able to absorb nutrients in adverse conditions will once again play a much more important role than we see at present.

About Dr. Rolf Sommer

Rolf Sommer heads the Agriculture and Land Use Change department at WWF (World Wide Fund for Nature), one of the world’s largest nature conservation organizations. Sommer has a doctorate in agricultural science and a degree in biology, and has dealt for the past two decades with sustainable agriculture and soil fertility. He has worked on international projects in Africa, Asia and Latin America, and written various publications, also on the topic of carbon storage in soils.

Agriculture alone is often the target of public criticism, even though it ensures that people have food. How can society and politics accommodate the farmers?

We need much greater recognition for agriculture and food production in Germany. Good food must have its price. Farmers must be paid for producing this good food without harming the environment. Selling off food cheap has to stop. Of course, it’s the consumer at the check-out who has control over what food they buy. But that’s only part of the solution.

What else are you thinking of?

We need political solutions. Fair prices must also be paid for good food and good professional farming practice. Finally, we as a society must ask the question, what kind of agriculture do we want? What price do we want to pay for food? If we want more environmental protection in agriculture then we need a real transformation. That’s possible. We have the solution! Society, government and agriculture can and must pull together – and then we can achieve that together.

Back to the "World of Farming" main page

Your contact

Stephan Krings
Stephan Krings
Send email