Dryland ecosystems cover about 40% of land on earth and support more than 2 billion people, and once degraded, they are difficult to restore. One technique for restoring dryland ecosystems with native plants —— direct seeding — is promising, but has many disadvantages. 

"In degraded drylands only around 10% of directly sown seeds actually establish them selves, "says Frederick Dadzie, PhD candidate at UNSW. "And given that native seeds are expensive and often in low supply, this is full of problems. "

Since one of the potential issues of degraded drylands is an absence of native microorganisms in the soil, the research team acquired native microorganisms from undisturbed sites and grew them. They then introduced them to soil that contained the seeds of native plants and planted them in degraded drylands. 

They found that microorganisms were very beneficial for getting the plants established. especially at the earlier stages when the seeds were growing to seedlings(树苗). After that, the relationship was less clear. 

"That microorganisms improve germination(发芽)in degraded habitats is good news for ecosystem restoration, " says Mr. Dadzie. "And what's better: this is a simple, two-step process that can be applied to restoring dryland ecosystems. First, combining the seeds and soil into pellets(小球), and second, providing those pellets with the microorganisms. "

"Not only are drylands valuable as food bowls for vast numbers of people, but they also provide other services, "says Mr. Dadzie. "Due to the vastness of drylands, they have the highest potential to absorb atmospheric carbon and therefore contribute substantially to climate change. "

While this study was conducted at a field site，the seedlings were provided with both shade and water. In the future，similar experiments should be repeated but under more naturalized conditions with environmentally determined sun and rain.