Restoring grasslands and other ecosystems that have been destroyed by agriculture can take decades. But a team of ecologists from The Netherlands says it has discovered a way to do it in just six years—by “inoculating” the degraded soil with a thin layer of soil from a healthy field, according to a study published in the journal Nature Plants.
Soil contains a complex array of bacteria and microorganisms, and “[e]cologists have long known that these underground communities build critical partnerships with the plants growing nearby,” says Science, in a report on the study. “But many of these partnerships remain a mystery. Small-scale studies in greenhouses have shown that adding the right soil can promote the growth of a particular plant community, and some researchers have even tried soil transplantation—replacing one soil with another—to get certain endangered plants to grow.”
But transplantation is a costly and long process. In an effort to find a quicker, more efficient way to replenish soil, the team from the Netherlands Institute of Ecology, led by E.R. Jasper Wubs, added thin layers of healthy soil to a series of degraded farm plots. They added seeds from a variety of plant species and habitats. After six years, “[t]he added soil made the existing land richer—as the researchers found more nematode worms, more bacteria, and more fungi in those sections of the plots.”
The need for more effective land-restoration efforts is growing worldwide, as “many once-fertile lands are turning into desert, and a significant amount of agriculture is lost every year,” says Science.
Already, land managers in the Netherlands are using Wubs’s soil inoculation to promote restoration at 15 different sites, a strategy the European Union may choose to incorporate as it intends to restore 15 percent of degraded ecosystems by 2020.