Climate change is changing our food

No beer, no bread, no fries anymore?

Read out

French fries become poisonous, beer stops frothing and baking bread becomes impossible - greenhouse gases in the air not only change the climate, but also our food. This is confirmed by experiments at the University of Hohenheim. In high-tech field experiments, agricultural biologists have exposed wheat, barley and potatoes to the environmental conditions of the future. Conclusion: Not only the yields, but also the compositions of the plants change - and not necessarily for the better.


According to the machines from the cellar of the Ecology Center of the University of Hohenheim, Professor Andreas Fangmeier from the Institute for Landscape and Plant Ecology stands in the middle of the room and examines various plants that are used in the six climatic chambers to measure their size. "The special thing about it is that we can simulate the climate and the CO2 concentration of the future in the climate chambers with the aim of testing the quality of the fruit, " explains Fangmeier. In the chambers are tomatoes, sauerkraut and soybeans, which are set in a Mediterranean climate. In addition, in three of the six chambers, the plants must cope with an increased CO2 concentration. This concentration corresponds to a value that is expected on Earth in 50 years.

Greenhouse gas reduces quality

In the past, barley, wheat and potatoes were subjected to similar experiments by the Hohenheim plant ecologists and the quality of the fruit was analyzed. The result is sobering: "Due to the increased CO2 value in the air, the plants grow better and produce a larger yield, but the quality of the crops deviates from the normal state, " says Fangmeier. "Bread can no longer be baked because of the lack of stickiness of wheat, beer can foam less and fries could even be toxic to humans." And because the plants for animal feed are also less nutritious, farmers have to feed larger quantities.

Nitrogen balance changed

This is mainly due to altered protein concentrations in the plants. Because under increased CO2 most plants need less protein and thus less nitrogen in the leaves - and then have less nitrogen available, which they can transport during maturation in the fruit. display

"The future air composition causes certain enzymes in the plant to work more effectively and the plants absorb less nitrogen. Other micronutrients, which are important for our diet, the plant absorbs only limited. In 50-100 years, today's varieties will no longer provide the harvest quality we need under these changing climatic conditions. Our results show that we need new or modified plant species for food production in the future, "explains the researcher.

Also affected energy crops?

In addition to the climate chambers, Fangmeier also researches rape plants in the field. The plants grow in so-called FACE systems (Free Air Carbon Dioxide Enrichment) from CO2 fumigation rings, each with a diameter of two meters, in the soil. The special thing about it: The rapeseed grows under real conditions, in terms of the weather, but under increased CO concentration.

"Rapeseed, although versatile in human use, has received little attention in CO2 research so far. He is food and feed supplier on the one hand and biodiesel raw material on the other, "says Fangmeier. After the harvest, the energy content of the plant for diesel production, as well as the quality as feed or

Food plant for animals and humans to be tested.

(University of Hohenheim, 11.04.2007 - NPO)