View Single Post
Old 07-23-2011, 12:29 AM   #2
Ben
Member
 
Ben's Avatar
 
Join Date: Mar 2011
Location: Three Rivers Station, Meekatharra
Posts: 70
Default

cont from above...

Allan Savory, in his laconic way, makes it all sound elementary. "All we've done really is make the rainfall more effective." Parched and unproductive regions throughout the world are not necessarily suffering from less rain, he says. The problem is that the water leaves too quickly, through runoff or evaporation from bare soil. Water needs to infiltrate and remain in the soil, entering the stream and river system, and leave only through plant growth or by entering aquifers. "All of this we're doing with the livestock," says Savory. "We keep operating on sound scientific principle, enhancing the organic matter and porosity of the soil, and keeping water in the system."

The key to improving water conditions lies in the carbon cycle. In Savory's words, "The fate of carbon and water tend to follow each other." Carbon in the soil acts as a giant sponge, keeping rain water in the ground rather than allowing it to stream off. "Every one-percent increase in soil carbon holds an additional 60,000 gallons of water per acre," says Steven Apfelbaum, founder of Applied Ecological Services, Inc., a landscape-restoration company based in Brodhead, Wisconsin. "This means reduced erosion and sedimentation and downstream flooding."

Desertification—and associated problems such as flooding, wildfires, and water shortages—can be seen as a symptom of the carbon cycle gone awry, says Savory. In the same way that plants need animals, as seen in the relationship between ruminants and grasses, soil needs plants. "For soil to form, it needs to be living, and to be living, soil needs to be covered," says Australian scientist Christine Jones. Without a cover of plants in various stages of growth and decomposition, much of the carbon oxidizes and enters the atmosphere as CO2.

So soil carbon has huge implications for climate change. Rattan Lal, Distinguished Professor of soil science in the School of Environment and Natural Resources at Ohio State University, estimates that soil-carbon restoration can potentially store about one billion tons of atmospheric carbon per year. This means that the soil could effectively offset around one-third of human-generated emissions annually absorbed in the atmosphere. Building soil carbon would also enhance food production; and, because carbon-rich soil holds significantly more water than its dried-out counterpart, it would help to secure watersheds and protect against flooding and drought.

"I teach my students that the goal [in agriculture] is to produce a positive carbon budget: the amount of carbon returned to the land should be more than the amount that is leaving the land," says Lal, noting that soil-carbon levels worldwide are dropping wherever extractive farming is practiced. He says much of Africa, Asia, and parts of Central Asia have soils which contain as little as 0.1 percent carbon, whereas the minimum for functionality is 1.5 percent to two percent. Savory's model, he says, offers valuable insight on how to increase soil-carbon levels and therefore increase fertility.

Despite his evident successes, Savory still occupies an equivocal position in the ranching and agricultural world. His methods have stirred surprising passions not only among farmers and ranchers who have used them with success but also among skeptics and detractors, who have called them "hocus-pocus" and "more religious belief than science." Savory himself has been likened to "the Wizard of Oz"—big on fanfare, empty of real ideas.

This may be as much about delivery as about science. Part of the resistance stems from the far-reaching nature of Savory's claims. Some skeptics who might be receptive to his ideas in the realm of animal husbandry balk at proclamations of a total "paradigm shift" with the ambition to rethink agriculture from the ground up. Others associate the language of his programs—"holistic management," "holistic decision-making"—with a New Age sensibility that seems unscientific. Then there's the inevitable resistance to new ideas, especially ones that bypass established business and technological systems. Apfelbaum says that most practitioners who balk at holistic management "simply are skeptical of change from their status quo and 'the way ranching has always been done.'"

Another factor is that Savory's system is less a recipe than a way of understanding the land. This means that even when his methods work, it can be hard to know exactly what prompts success. George Wuerthner, a photographer and author who has written extensively about western landscapes, says, "One thing Savory's methodology does is make ranchers pay more attention to what they're doing on the land. That may help in and of itself, regardless of the ecological assertions, which I don't buy."

Some ecologists are also concerned by the impression that Savory promotes "bring in the cows" as a one-size-fits-all panacea. These critics often conflate planned holistic grazing, which involves continual monitoring and adjustment, with more formulaic grazing strategies such as "short intensive grazing" (scheduled on-off grazing cycles) and, the latest craze, "mob grazing" (very large herds moved several times a day). "Grasslands are tremendously diverse," says Jason Neff, associate professor of geological sciences at the University of Colorado at Boulder. "Some have been grazed for thousands of years, and some not at all. You need to look at the cultural and ecological history of a place. I work in semi-arid lands that are sensitive to grazing. For example, the Colorado plateau—increase grazing out there, and the land will suffer."

Savory himself does not claim that his methods are equally applicable everywhere. They must take the specific local ecology into account and are best suited to what he calls "brittle environments," parts of the world that are dry most of the year, with seasonal rainfall. These areas are less forgiving of land management problems than are more temperate regions: "If, say, England had the climate of Israel, it would have desertified," he says. "The dry periods show up the faults [in how the land is managed]." But given that the grassland, rangeland, and savanna—where holistic management is most successful—cover two-thirds of the world's landmass, the potential of his ideas is still vast.

The strength of Savory's ideas may derive from the fact that he brings an outsider's eye—even a poet's eye—to environmental cycles. (Nature writer Gretel Ehrlich, who has spent time with Savory in the African bush, calls him "the best observer of wildlife I've ever met.") Seen from a holistic perspective, the secret of Dimbangombe is no secret. It simply required looking back to the land's prehistory—and learning a management principle from no management at all.

http://www.guardian.co.uk/environmen...climate-change
__________________
Turning red to green, a million acres at a time.
Ben is offline WA Australia   Reply With Quote