Thanks. I have watched that video a couple of times, and enjoyed watching it again. It is excellent, and a good reminder of why we here are learning and practicing permaculture. When I watch that video, and the others Geoff has done, I am encouraged that if they could do what they did, and make such a huge difference, I can do that with my little projects too.
I watched this video, as well at the Allan Savory TED talk about greening the desert (see http://www.youtube.com/watch?v=vpTHi7O66pI if you haven't seen it). In his talk, Allan Savory (who emphasizes introducing herds and moving them around) dismisses the approach that Liu recommends (planting native species). They both have beautiful before and after pics but I was sort of curious if anyone else had seen the two and can square them.
I just rewatched both videos. I think it is a reminder that there are many tools in the permaculture toolbox, and many approaches to healing degraded landscapes. Permaculture is not a one size fits all approach. Actually, the take I got from the 2nd vid was that it was the princess of Jordan that was encouraging natives, as being better adapted to the local situation and climate. Sometimes it is also true that the former "natives" are no longer adapted to the current situation, as well. And Bill Mollison said he only uses natives-- "anything native to this planet."
In the video, they were excluding animals, for several years, to give the vegetation a chance to regrow. But too much rest can also be degrading, as Alan Savory discussed. Dan Dagget (Gardeners of Eden) talked a lot about the negative consequences of excluding animals, showing many places that are healthier and much more richly vegetated by using animals properly--and that is an important consideration. Joel Salatin also uses animals to improve his pastures, by rotating them around the pastures. It does require different management techniques, not just letting them go anywhere and eat off each bit of green.
Each person who practices permaculture will be in a different situation, different climate, different soil types, rainfall, elevation, etc. So, in my opinion, we all need to study and observe the particular place we are designing, and try different approaches. As Alan Savory pointed out, humid climates are very different from those with wet/dry cycles. Grasslands need a different approach than forested areas. Also, some of the areas Geoff Lawton and John D Liu worked with were so degraded, there was nothing left to regrow, whereas the grasslands Alan Savory was managing were still grassed, just very sparse grass with bare earth between the clumps, and tall dead grasses that did not decompose.
I saw an example of that on my piece of high desert last year. The bunch grasses had tall, dead growth that was crowding out the new growth. After we went through with a scythe and mowed it down, even using a garden rake to clean out the dead grass, the clumps seem a lot healthier this year. Alan Savory was using animals to mow down and trample the dead grasses and leave them on the ground as mulch. We do that on a smaller scale in our gardens when we collect and spread mulch to shade and protect the soil and allow a healthy microclimate to develop.
Another experience: I have read suggestions to just pile up organic matter and let it sit for a year, to make compost. I tried that 2 years ago, using bins made from old pallets, and adding water as I built the piles, and while watering the garden in the summer, but in my dry climate, a year later, when I dug into my piles, the dead grasses and weeds, spoiled hay and straw, and leaves, etc, all looked just exactly like they did when I piled them up. The piles were just too small, and the intense sun and superdry air sucked all the moisture out. I finally realized that I had to make a much bigger pile (about 10 feet across) with plenty of water, and covered with a tarp, then turn and chop and rewet it, etc, and finally I got some compost! This is just an example of how different techniques may be needed in different places, and what works well in one place may not work at all or without considerable modification in another area.
The greening of massive spaces, using any one of these methods, could assist greatly in places like Colorado and Australia where wildfires are a serious threat. John Liu and Allan Savory have both successfully implemented large scale wildfire prevention systems that most don't even know exist. I like the idea of greening huge spaces with the specific intent of wildfire prevention. And I'll repeat: greening lodgepole pine forests anyone?