Converting wild lands to agriculture can negatively impact wildlife, but according to a recent study, intensifying agriculture on existing farmlands can also come with a cost in different regions and can be reduced in different ways.
“On a global scale, many people have advocated for agricultural intensification based on the idea that it’s less problematic to stay in the same area than to convert additional habitats to cropland,” said Lukas Egli, a PhD student at Gottingen University and lead author of the study published in Global Change Biology.
To test the effects of intensification, Egli and his colleagues collected information from global datasets of the allocation and yields of important crops such as wheat, soy and maize. They also collected information about how much yield farmers would achieve with intensification.
They then collected biodiversity information from the International Union for Conservation of Nature and other organizations on mammals, amphibians and birds. This included global range data for almost 20,000 species as well as habitat preferences. They particularly paid attention to how species might respond to agriculture intensification within habitat groupings. Forest specialists don’t use agricultural areas as habitat, for example, but deer do.
They then combined the biodiversity distribution data with land cover data to determine where preferred habitat occurred in the ranges globally, and then looked at how much preferred habitat was located in agricultural areas.
“Assuming for a certain species, most of their habitat is located within agricultural areas, these areas will be very important for survival of the species,” Egli said. “If you completely intensify agriculture, this species is likely to go extinct.”
Then, the team looked at how much biodiversity value would change if they increased intensification.
Egli and his colleagues found that agriculture planning matters. Projecting to 2040, the team determined that in a “business as usual scenario,” biodiversity would be reduced 11 percent by 2040. Iimplementing spatial planning for agriculture, however, could reduce the impact by 61 to 88 percent. “The basic finding is it does make a large difference where you go to intensify,” he said.