söndag 20 februari 2011

Sustainable water and food

Brad Lancaster talks about his evolution into rainwater harvesting, and the current state of our freshwater resources. Filmed at Santa Barbara City College Lifescape Garden.
http://www.youtube.com/watch?v=2iQ-FBAmvBw&feature=related

Girja Sharan, a Hydrolic engeneer finds a way of solving the drinking water crisi with condensation
http://www.youtube.com/watch?v=sJJh3AQ_u6U&feature=related

Turning air into water
http://www.youtube.com/watch?v=MEqCyAe_ClM&feature=related

Grazing at Joe Salatins Pholypace Farm
"The simplest way to capture the sun’s energy in a form food animals can use is by growing grass: “These blades are our photovoltaic panels,” Joel says. And the most efficient – if not the simplest – way to grow vast quantities of solar panels is by management-intensive grazing, a method that as its name implies relies more heavily on the farmer’s brain than on capital – or energy intensive inputs. All you need, in fact, is some portable electric fencing, a willingness to move your livestock on to fresh pasture every day.”

”The imporant thing to know about any grass is that its growth follows a sigmoid, or S , curve, Joel explained. He grabbed my pen and notebook and began drawing a graph, based on the one that appears in Voisin’s book. “This vertical axis here is the height of our grass plant, okay? And the horizontal axis is time: The number of days since this paddock was last grazed.” He started tracing a big S on the page, beginning in the lower left-hand corner where the axis met. “See, the growth starts out real slow like this, but then after a few days it begins to zoom. That’s called the “the blaze of growth”, when the grass has recovered from the first bite, rebuilt it’s reserves and root mass, and really taken off. But after a while”- the curve leveled out and around day fourteen or so-“it slows down again, and the grass gets ready to flower and seed. It’s entering a period of senescence, when the grass begins to lignify (get woody) and becomes less platable to the cow. “What you want to do is graze pasture right at this point here “- he tapped my pad sharply-“ at the very top of the blaze of growth. But what you never, ever want to do is to violate the law of the second bite. You can’t let your cows take a second bite of grass before it has had a chance to fully recover”.

“Management intensive it is. Joel is constantly updating the spreadsheet he keeps in his head to track the precise stage of growth the farm’s several dozen paddocks, which range in size from one to five acres, depending on the season and the weather. The amount of time it takes a paddock to recover is constantly changing, depending on temperature, rainfall, exposure to the sun, time of year, as does the amount of forage any given cow requires, depending on its size, age, and stage of life: a lactating cow, for example, eats twice as much grass as a dry one.

As destructive as overgrazing can be to a pasture, under grazing can be almost as damaging, since it leads to just right – grazing the optimal number of cattle at the optimal moment to exploit “the blaze of growth “ yields tremendous amounts of grass, all the while improving the quality of the land. Joel calls his this optimal grazing rhythm “pulsing the pastures” and says that at Polyface it has boosted the number of cow days to as much as four hundred per acre; the county average is seventy. “In effect we’ve bought a whole new farm for the price of some portable fencing and a lot of management”.

Sissy Farmer (Joel Salatin on Forgiveness)
http://www.youtube.com/watch?v=jHOYn6RjCLY&feature=related

The above quotes about Joel Salatin are taken from the book below:

The Omnivore's Dilemma for Kids: The Secrets Behind What You Eat [Paperback]
Michael Pollan

http://www.amazon.com/Omnivores-Dilemma-Natural-History-Meals/dp/0143038583/ref=ntt_at_ep_dpt_1

Converting cropland to perennial pastures produces healthier meat, builds better soil and combats climate change
http://www.motherearthnews.com/Sustainable-Farming/Grass-Fed-Meat-Benefits.aspx

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