Citrus fruits, coffee and avocados: The food on our tables has become more diverse in recent decades.
Citrus fruits, coffee and avocados: The food on our tables has become more diverse in recent decades. However, global agriculture does not reflect this trend. Monocultures are increasing worldwide, taking up more land than ever. At the same time, many of the crops being grown rely on pollination by insects and other animals. This puts food security at increased risk, as a team of researchers with help from Martin Luther University Halle-Wittenberg (MLU) writes in the journal "Global Change Biology". For the study, the scientists examined global developments in agriculture over the past 50 years.
The researchers analysed data from the United Nations’ Food and Agriculture Organization (FAO) on the cultivation of field crops between 1961 and 2016. Their evaluation has shown that not only is more and more land being used for agriculture worldwide, the diversity of the crops being grown has declined. Meanwhile, 16 of the 20 fastest growing crops require pollination by insects or other animals. "Just a few months ago, the World Biodiversity Council IPBES revealed to the world that up to one million animal and plant species are being threatened with extinction, including many pollinators," says Professor Robert Paxton, a biologist at MLU and one of the authors of the new study. This particularly affects bees: honeybees are increasingly under threat by pathogens and pesticides, and populations of wild bees have been on the decline around the world for decades.
Fewer pollinators could mean that yields are much lower or even that harvests fail completely. However, risks are not spread equally across the world. The researchers used the FAO data to create a map showing the geographical risk of crop failure. "Emerging and developing countries in South America, Africa and Asia are most affected," says Professor Marcelo Aizen of the National Council for Scientific and Technological Research CONICET in Argentina, who led the study. This is not surprising, he says, since it is precisely in these regions where vast monocultures are grown for the global market. Soy is produced in many South American countries and then exported to Europe as cattle feed. "Soy production has risen by around 30 percent per decade globally. This is problematic because numerous natural and semi-natural habitats, including tropical and subtropical forests and meadows, have been destroyed for soy fields," explains Aizen.
Read more at Martin-Luther-Universität Halle-Wittenberg
Image: A honey bee worker and a male mining bee on an apple flower. (Credit: Martin Husemann)