How to Reverse Desertification. With Rocks.

From a fanciful Sahara forest concept to the planting of trees to stop the encroachment of desert, we've seen plenty of ideas for turning arid, hostile environments into productive ecosystems.

The work of permaculture expert Geoff Lawton is often quoted in this regard. From exploring existing, 2000-year-old food forests to greening the deserts of Jordan, he's been talking about and teaching dry land permaculture concepts for many years.

His latest video look at the use of "gabions" or simple rock walls as a means to slow down the flow of flood waters, encourage the build up of silt and organic matter, and begin the process of natural regeneration.

A word of warning, however. When I posted Geoff Lawton's video about growing an oasis in the deserts of Jordan, at least one commenter was concerned about a lack of transparency, empirical data or proof of replicability.

It's a fair concern.

While permaculture continues to get huge attention around the world, and I've seen plenty of interesting and seemingly productive gardens, it would be nice to see more permaculture enthusiasts engaging in peer-reviewed research so we could tell if ideas are replicable.

There's much to be said for common sense, observation and landscape literacy, of course. And I think that's one of the key skills that permaculture courses offer—a sense of discipline regarding assessing the resources you have available and shaping your designs accordingly. Yet from the chicken greenhouse as permaculture cliche to volunteerism replacing cheap oil, the permaculture movement needs to apply critical thinking and engage with the broader research community if its ideas are going to take off.

I'd love to hear from readers about any peer-reviewed research into permaculture-based efforts to reverse desertification.