Last year, the United States of America imposed tariffs of up to 25% on goods imported from China. The Chinese government reacted by imposing tariffs of 25% on US goods, including US soybeans. Exports of US soybeans to China in 2018 dropped by 50%, even though the trade war had begun in the middle of the year only. Replacement may be provided by Brazil. This might have dramatic impacts on the rainforest, KIT experts warn.

"As a consequence of the trade war, we fear large-scale deforestation in Brazil. In the past, exponential increase in global soybean demand regularly led to deforestation in the Amazon rainforest to create new cultivation areas. In 2016, China imported 37.6 million tons of soybean from the US, which now have to be supplied by other producers. Brazil is the only country which could satisfy Chinese demand quickly enough," says climate researcher Richard Fuchs. Together with his colleagues Calum Brown and Mark Rounsevell from the Atmospheric Environmental Research Division of KIT's Institute of Meteorology and Climate Research and other European scientists, he studies potential impacts and warns of the consequences in a comment of the Nature magazine.

Brazil is by far the largest producer of soybeans, followed by the US and Argentina. Around 90 other countries, including China itself, together produce just about as much soybeans as Brazil alone. In the course of the US-China trade war, China's soybean import from Brazil climbed to a new record value of 75%. Soy is a crop that is mainly used as animal feed in meat industry. To an increasing extent, it is applied for the production of biofuel.

"In our opinion, it is most likely that Brazil will ramp up its production to satisfy the additional Chinese soybean demand. To achieve that, Brazil needs to increase the current area of soybean production by up to 39%. This would require up to 13 million hectares of additional land, likely to be tropical forests and corresponding to an area similar to Greece. In 1995 and 2004, the country's two peak deforestation years, 3 million hectares of rainforest were lost each year. Taking these rates, it would require only four years to provide enough area for Chinese soybean consumption. We urge the United States and China to acknowledge their roles in indirectly driving deforestation and to accordingly modify their trade agreements by removing tariffs from soybeans."

Apart from quick countermeasures of the US and Chinese governments, the scientists comment, other measures might also contribute to reducing the pressure on the Amazon rainforest partly at least. China could buy more soy from Argentina or the European Union and, at the same time, soybean producers in these areas could try to increase their harvests. Europe, however, would have to reconsider its opposition to genetically modified soybeans that is presently preventing large-scale cultivation. In the scientists' opinion, China also should increase own production.

Since 2000, China's cultivation area has decreased by about 25%, because it is cheaper to import soy from Brazil and the US and because Chinese agriculture has been damaged strongly by high fertilization, soil erosion, and use of pesticides. Governments worldwide should attach higher priority to protecting the remaining Amazon rainforest and encourage the Brazilian government to enhance environmental protection in this region. If they fail, ambitious climate protection and biodiversity goals would be at stake.

To sustainably cope with this problem, however, Fuchs only sees one option: "Ultimately, global meat consumption has to be reduced. Such a change will not be reached by appeals, campaigns to change consumer behavior, or eco-labeling of sustainable production. In our view, ecological consequential costs need to be included in food costs. Also bioenergy products, such as biodiesel, have to become more expensive."

However, there is not much time left for the world's community to prevent massive deforestation in Brazil: "Governments, producers, regulators, and consumers must act now. If they do not, the Amazon rainforest could become the greatest casualty of the US-China trade war."