Elizabeth Pennisi writes:

The red, orange, and spotted mushrooms that sprout up after it rains are doing more than adding color to the landscape. The fungi that produce them could be keeping the natural world productive and stable, according to a new study. Indeed, they may be critical to the health of Earth’s ecosystems, says Matthias Rillig, a soil ecologist at the Free University Berlin who was not involved with the work.

There are 70,000 known kinds of fungi. These include the yeast we use to bake bread, as well as molds, lichens, mushrooms, toadstools, and puffballs. They also include a wide variety of pathogens, from those that cause athlete’s foot in humans to those that inflict billions of dollars of damage on wheat, maize, and other crops.

Many of these fungi live belowground, but researchers have traditionally paid little mind to them. In the past few years, however, ecologists have realized that some—such as soil fungi called mycorrhizae—form vast underground networks that connect trees and supply them with nutrients, enabling a forest to thrive.

Might other soil fungi be playing a similar role aboveground? To find out, Manuel Delgado-Baquerizo, an ecosystem ecologist at the Spanish National Research Council, teamed up with colleagues around the world who had systematically collected and analyzed local soil samples—and the fungi they contained—for different projects. In total, the team analyzed nearly 700 samples from tropical, temperate, and polar climates. [Continue reading…]