Farming a saltwater plant that could feed the world and its vehicles

THE OLD MAN & THE SEA

Posted online: Sunday, July 27, 2008 at 1304 hrs Print Email

Farming a saltwater plant that could feed the world and its vehicles, a physicist from the Arizonian dust bowl dreams of greening desert coastlines

A few miles inland from the Pacific Ocean, amid cracked earth and mesquite and sun-bleached cactus, neat rows of emerald plants sprout from the desert floor. The crop is salicornia. It is nourished by seawater flowing from a man-made canal. And if you believe the American who is farming it, this swath of green has the potential to feed the world, fuel our vehicles and slow global warming.

He is Carl Hodges, a Tucson, Arizona-based atmospheric physicist who has spent most of his 71 years figuring out how humans can feed themselves in places where good soil and fresh water are in short supply. The founding director of the University of Arizona’s Environmental Research Lab, his work has attracted heads of state, corporates and Hollywood stars, among them Martin Sheen and the late Marlon Brando.

Hodges’ knack for making things grow in odd environments has been on display at the Land Pavilion in the Epcot theme park at Walt Disney World in Florida and the Biosphere 2 project in Arizona. Here in the northern Mexican state of Sonora, he wants to channel the ocean into man-made “rivers” to nourish commercial aquaculture operations and crops that produce food and fuel. This greening of desert coastlines, he said, could add millions of acres of productive farmland and sequester vast quantities of carbon dioxide. It also could neutralise sea-level rise.

Analysing recent projections of ice melt occurring in the Antarctic and Greenland, Hodges calculates that diverting the equivalent of three Mississippi rivers inland would do the trick. He figures that would require 50 good-sized seawater farms that could be built within a decade if the world gets cracking. “This is the big idea” that humanity has been waiting for, he believes.

Experts including Dennis Bushnell, chief scientist at NASA’s Langley Research Center, say seawater agriculture could prove to be an important weapon in the fight against climate change. Hodges already has built such a farm in Africa. Political upheaval there shut much of it down in 2003. He’s determined to construct a showcase project in North America. All he needs now is $35 million. That’s where salicornia comes in.

A so-called halophyte or salt-loving plant, the briny succulent thrives in hellish heat and pitiful soil on little more than a regular dousing of ocean water. Several countries are experimenting with salicornia and other saltwater-tolerant species as sources of food. Known in some restaurants as sea asparagus, salicornia can be eaten fresh or steamed, squeezed into cooking oil or ground into a high-protein meal.

Hodges, who heads the nonprofit Seawater Foundation, plugged salicornia as the plant to help end world hunger. When oil prices exploded, he saw his shot to lift the shrub from obscurity. Salicornia can be converted into biofuel. And, unlike grain-based ethanol, it doesn’t need rain or prime farmland, and it doesn’t distort global food markets. NASA has estimated that halophytes planted over an area the size of the Sahara Desert could supply more than 90 per cent of the world’s energy needs.

Last year, Hodges formed a for-profit company called Global Seawater Inc to produce salicornia biofuel in liquid and solid versions. It recently planted 1,000 acres of salicornia in rural Sonora. That crop will provide seed for a major venture planned 50 miles north in the coastal city of Bahia Kino. Global Seawater is attempting to lease or buy 12,000 acres there for what it envisions will be the world’s largest seawater farm.

The plan is to cut an ocean canal into the desert to nourish commercial ponds of shrimp and fish. The effluent would be channelled further inland to fertilise fields of salicornia for biofuel. The seawater’s next stop would be man-made wetlands. These mangrove forests could be “sold” to polluters to meet emissions cuts mandated by the Kyoto Protocol on climate change. “Nothing is wasted,” Hodges said. Global Seawater already has a small refinery to process salicornia oil into liquid biodiesel, which Hodges believes can be produced for at least one-third less than the current market price of crude oil. Leftover plant material would be converted into solid biofuel “logs” that he said burned cleaner than coal or wood.

NASA is interested in testing fuel from Hodges’ halophyte. So are cement makers and other heavy industries. Retired executives from major corporations are helping Global Seawater raise capital. But some environmentalists are dubious. Channeling millions of gallons of seawater inland could have unintended consequences for fragile deserts, said biologist Exequiel Ezcurra, former head of Mexico’s National Ecology Institute. Hodges says his project has met all environmental requirements posed by Mexico. His work on shrimp cultivation fuelled the explosion in Mexico’s aquaculture industry. The leader of Abu Dhabi sent his lab $3.6 million on a handshake to build a saltwater greenhouse system for growing vegetables.

Bushnell praised Hodges’ science as “superb” but said algae might prove to be the best plant-based biofuel because it can produce much more fuel per acre. Hodges is “a pioneer,” Bushnell said, “but first-movers generally aren’t the successful ones at the end.” Said Sheen, “We have to be outrageous in our efforts to solve” climate change. “Carl is on a mission to save the world.”
-Marla Dickerson (los Angeles Times)