Prev Previous Post   Next Post Next
Old 07-23-2011, 12:28 AM   #1
Ben's Avatar
Join Date: Mar 2011
Location: Three Rivers Station, Meekatharra
Posts: 70
Default Greener pastures: How cows could help in the fight against climate change

Greener pastures: How cows could help in the fight against climate change

Greener pastures: How cows could help in the fight against climate change. What goes on in the stomachs and under the hooves of cows might be the key to turning deserts back into grasslands

Part of the Guardian Environment Network, Friday 22 July 2011 14.49 BST

In reports of rising CO2 levels, it's easy to get the impression that the carbon-and-oxygen molecule is a kind of toxin, some alien vapor coughed up by a century-plus of heedless industrialism now coming back to haunt us. But on closer inspection, it seems that the problem isn't the carbon itself—it's that there's too much in the air and not enough in the ground.

When we consider our CO2 predicament, we tend to fault our love affair with the car and the fruits of industry. But the greater culprit has been agriculture: since about 1850, twice as much atmospheric CO2 has derived from farming practices as from the burning of fossil fuels (the roles crossed around 1970). Over the past 150 years, between 50 and 80 percent of organic carbon in the topsoil has vanished into the air, and seven tons of carbon-banking topsoil have been lost for every ton of grain produced.

So, how do we get that carbon out of the air and back into the soil? Some suggest placing calcium carbonate or charcoal (aka "biochar") directly into agricultural soil (see "Black Is the New Green," Conservation, Summer 2010). But a growing number of soil and agricultural scientists are also discussing a low-tech, counterintuitive approach to the problem that depends on a group of unlikely heroes: cows. The catalyst for reducing CO2 and restoring soil function and fertility, they say, is bringing back the roving, grazing animals who used to wander the world's grasslands. The natural processes that take place in the digestive system and under the hooves of ruminants might be the key to turning deserts back into grasslands and reversing climate change. In other words, a climate-friendly future might look less like a geo-engineered landscape and more like, well, "Home on the Range."

Perhaps the most steadfast advocate of this future is Allan Savory. A 76-year-old native of Zimbabwe, Savory has the relaxed, weathered look of a lifelong outdoorsman more attuned to the etiquette of the bush than that of the boardroom. In the 1960s, as a young wildlife biologist in what was then called Southern Rhodesia, he noticed that, when livestock were removed from land set aside for future national parks, "almost immediately, these wonderful areas suffered severe loss of both plant and animal species." Cattle, he began to realize, could play—if properly managed—the crucial role in grassland ecology that used to be occupied by herds of wild herbivores. They could help prevent and even reverse land degradation and the desertification of grasslands, combating in the process both human poverty and the disappearance of wildlife. Over the course of several eventful decades—during which he was elected to the parliament, served as an opposition leader against Rhodesia's white-minority government, and spent four years in political exile—Savory developed a program to put these ideas into action.

Savory's singular insight is that grasslands and herbivores evolved in lockstep with one another. This means that to be healthy, grasses need to be grazed. Animals eat plants and stimulate their growth; they cycle dead plants back to the surface, which allows sunlight to reach the low-growing parts; their waste provides fertilizer. When a predator—say, a lion—comes into this bucolic scene, the animals bunch together and flee as a herd, their hooves breaking up and aerating the soil. Then, on a new patch of land, the process starts again. This way all plants get nibbled, but none are overgrazed. And none are overrested, which leads to accumulated dead plant material that blocks sunlight and hinders new growth.

To Savory, the conventional wisdom that grazing degrades the land is an oversimplification; what matters is how livestock are applied. He readily acknowledges that the confined animal feeding operations usually associated with large-scale cattle ranching are problematic, and he opposes cramming cattle into lots on industrial farms. But he contends that this degradation by overgrazing is a matter of time rather than numbers; he's fond of saying that one cow continually foraging in one spot will do damage where a hundred moving from place to place will not. Where feedlots will harm the land, he claims, herds of well-managed grazing animals, nibbling on native grasses and roaming from spot to spot to elude predators and seek fresh pasture—managed in a way that mimics their behavior in the wild—will restore the land's natural dynamics.

For years, many in the academic and ranching establishment dismissed Savory as a gadfly, someone outside the agricultural and scholarly mainstream who did his research in the open air and presented his counterintuitive conclusions in unscientific language. Undeterred, Savory continued to refine his framework and expand his training programs, and today his successes have become hard to ignore. Farmers, ranchers, and other land stewards who have attended his training programs have brought land back from the brink across Africa, Australia, New Zealand, and the U.S. In 2010, his Zimbabwe nonprofit, the Africa Centre for Holistic Management, received a $4.8 million grant from the United States Agency for International Development (USAID) to expand its work in Africa. More recently, Savory won the 2010 Buckminster Fuller Challenge prize, a prestigious award that supports a proposal with "significant potential to solve humanity's most pressing problems."

The centerpiece of Savory's work is the 2,630-hectare Dimbangombe Ranch in northwestern Zimbabwe near Victoria Falls, home to his Africa Centre for Holistic Management. In the hot, dry, depleted landscape of this region, "the rains are not what they used to be" is a frequent refrain. But Dimbangombe looks as though it's been uniquely favored by the rain gods. It has lush, varied grasses, flowing rivers and streams, and thriving livestock—some four times the number of neighboring ranches. Thanks to the renewed flow of the Dimbangombe River, elephant herds no longer have to travel to pools but can water on the river. Women who used to walk as much as five kilometers daily for water now have it available in their communities. Dimbangombe has become productive and vibrant while its neighbors, and similar environments around the globe, are turning to desert. How? "Two things: we brought in increased cattle numbers with holistic planned grazing, and [we] minimized the fires," says Savory.

The Dimbangombe experiment began in 1992, when Savory donated land he had purchased in the 1970s to develop the ranch as a nonprofit demonstration site. (A larger parcel of land owned by Savory is now the Kazuma Pan National Park, part of the five-nation Transfrontier Conservation Area.) In the early days, when funds were tight, he generally camped on the land. Even now, Savory and his wife, Jody Butterfield, director of development at the Centre, live in a mud-and-thatch hut on the riverbank. Savory says this is "not a hardship, as I have lived much of my life like this and simply enjoy living amongst Africa's big game and wildlife more than in a house."

As the ranch grew, Savory and his colleagues ran cattle on the land, beginning with what they could afford. "We also invited farmers in the neighboring community who had run out of feed to add their cattle to the herd," Butterfield says. "They needed to keep their animals alive, and we needed numbers to restore the land. Sometimes we had 600 cattle, sometimes 300. We kept them constantly on the move."

The other key intervention, creating firebreaks, put a stop to uncontrolled clearing fires and to fires set by animal poachers, who sometimes torch the grass to obliterate their tracks. These woodland and grassland fires, Butterfield says, can go on for hundreds of miles. "Africa is burning to death, many parts of it," adds Savory. "809 million hectares of grassland are burned annually. The reason we're burning them is that there are not enough herbivores to keep the grass alive." What he means is that fires are used to clear decaying plant material and promote fresh growth—functions that grazing herbivores are uniquely equipped to do better. Savory contends that planned grassland fires cause numerous problems, including leaving exposed soil (which oxidizes and leads to runoff) and promoting fire-dependent plant species over the more diverse and soil-enriching grasses that animals eat. Another result of grassland fires is added atmospheric CO2. In one hour, says Savory, a half-hectare fire pumps as much CO2 and other pollutants into the air as 4,000 car trips.

With these strategies applied in Dimbangombe, "each year things got better and better," Butterfield recalls. "Gradually over the years, the grass was thickening up and the ground would close in, covered with plants. Then we started noticing, 'oh, the wetlands are expanding along the upper reaches of the river.' We started seeing sedges and reeds growing many yards up from the riverbanks and could now see a huge swath that was becoming wetland. In the past few years especially, it's been quite dramatic."

Turning red to green, a million acres at a time.
Ben is offline WA Australia   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT +9.5. The time now is 10:17 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Template-Modifications by TMS
Grazebook © 2011