Effect of inoculation with heathland soil after eight years (left: untreated control area; right: area where heathland soil was added)E.R.J. WUBSDonor-soil microbes drive—and can speed up—the restoration of degraded farmland, scientists at the Netherlands Institute of Ecology in Wageningen have shown. The results of a six-year field test, published today (July 11) in Nature Plants, show the greatest ecosystem repair in formerly arable fields in which the team removed a thick layer of existing topsoil before applying a thin layer of microbe-rich donor soil.
“Of course, seeds of plants were also present in the donor soil,” study coauthor Jasper Wubs of the Netherlands Institute of Ecology told reporters during a press briefing. “But our study shows that it is in fact the soil organisms—such as the bacteria, fungi, and roundworms—which determine the direction of ecosystem restoration.”
Wubs and colleagues tested various soil inoculation approaches in plots carved from a 160-hectare field in Reijerscamp, the Netherlands, that had been farmed for nearly 60 years. In control plots, the researchers left the land as it was. In experimental plots, they left behind existing topsoil or removed up to 50 cm before spreading a 1 cm-thick layer of donor-grassland or -heathland soil. While all the plots that received donor soil fared better ...
