Monday 21 March 2016
Wednesday 12 August 2015
Millions of ‘Shade Balls’ to Prevent Evaporation in California Reservoirs
Los Angeles officials have come up with a surprisingly low-tech way to fight the region's water crisis: millions of floating plastic balls.
As part of a $34.5 million project, the city's Department of Water and Power has released nearly 100 million of so-called "shade balls" into three local reservoirs in recent months. The layer of balls protects water from algae formation, dust, rain and wildlife.
Perhaps more importantly, the black balls also help to prevent evaporation. According to Los Angeles Mayor Eric Garcetti, the balls could conserve 300 million gallons of reservoir water each year -- water that California desperately needs.
On a chemical level, the balls prevent the production of bromate, a suspected carcinogen. Bromate forms when naturally occurring bromite reacts with added chlorine and sunlight.
Shade balls will likely become a permanent fixture atop reservoirs. This particular batch will be deployed for decade, after which time they will be removed, recycled and replaced.
"LADWP's innovative use of shade balls will protect our water supply and ensure that residents have access to clean, safe, and ready-to-drink water. As we work to ensure a more sustainable and resilient future for L.A., I look forward to more creative, trailblazing and cost-effective solutions," Los Angeles Councilmember Felipe Fuentes, chair of the city's Energy and Environment Committee, said in a news release.
Wednesday 22 July 2015
Can Breadfruit Overcome Its Past to Be a Superfood of the Future?
An unusual crop that was once a staple across the tropics seems to be making a comeback. Starchy and packed with nutrients, breadfruit isn’t a typical fruit. And while this cousin of the mulberry may not be at the top of anyone’s dream menu, it could be the key to food security in part of the world.
That’s because breadfruit is high in complex carbohydrates (the kind that are good for you), protein, and micronutrients like iron and zinc. And compared to white rice and potatoes, breadfruit scores lower on the glycemic index, so it won’t shock your blood sugar. That’s good news for the Pacific Islands where diabetes rates are soaring, largely due to the influx of imported processed foods.
There are also non-nutritional advantages. The hardy tree is low maintenance and doesn’t require agrochemicals, so breadfruit is organic. And it’s fairly efficient. “It yields a lot of food for the amount of space it takes up, which is important on islands with limited space,” says Diane Ragone, Director of the Hawaii-based Breadfruit Institute.
Ragone first learned about the potential of breadfruit while in graduate school. “I looked out at a hillside in Micronesia covered in breadfruit trees and realized that food forest was a long-term, sustainable system,” she says. Since then, Ragone has travelled the tropics assembling what is now the world’s largest breadfruit collection with more than 120 varieties. Through this effort she is conserving varieties that might otherwise go extinct.
As with any underutilized foodstuff, there are obstacles to getting people to eat breadfruit regularly. Many people in the Caribbean shun it for its history. First brought to the Caribbean from the Pacific by a British sea captain in the late 1700s, breadfruit was largely cultivated to feed slaves. That fact has given breadfruit a bad rap on some islands, but Ragone believes the attitude is changing, especially as people become more interested in eating healthy, local food.
There’s also the issue of shelf life. Once it’s ripe, breadfruit rots pretty quickly, which is an issue when you have hundreds of large fruits to harvest all at once. That’s why breadfruit advocates like Dr. Camille George, a professor of engineering at the University of St. Thomas in Minnesota, have beenpioneering ways to extend breadfruit’s shelf life by shredding and drying it.
With the help of her engineering students, George has developed low-tech, hand-powered tools to grind dried breadfruit into flour. “These are engineering solutions for the bottom billion,” says George, who wants to see breadfruit orchards become central to a new food economy in tropical places like Haiti. Her team has partnered with the Trees that Feed Foundation to distribute equipment in Haiti, Jamaica, and several other countries (the foundation also plants breadfruit trees for cultivation). Grinding breadfruit into flour can give people year-round access to a nutritious local foodstuff.
So what to do with all that flour? That’s something George and her breadfruit colleagues are working on. In August 2012, the Palmares Bakery opened in Haiti’s capital city, Port-au-Prince, offering breadfruit baked goods like cupcakes and cookies. Last year the bakery delivered around 100,000 cupcakes to school children. “Learning to work with a new type of flour which has its own particularities was one of our biggest challenges,” says Inette Durandis, who helps run the bakery and has worked on commercializing breadfruit in Haiti for the last nine years.
Figuring out how ordinary Haitians want to use the flour is another issue. “Since most people there don’t have ovens, it doesn’t really make sense to sell baking flour,” says George. She thinks making it into pasta or porridge might be a better approach. Later this year, an extrusion factory will open in Haiti to produce Cheeto-like breadfruit puffs. With savory and sweet options, the puffs are just one way advocates are trying to get more breadfruit into the Haitian diet. Organic and gluten free, breadfruit flour could have appeal on the international market too.
Perhaps it’s not the best-looking fruit or even the most intuitive to prepare, but breadfruit’s future looks promising. “People are really starting to accept and appreciate breadfruit,” says Durandis. In that case, it might not be long before breadfruit becomes a national product for Haiti or even turns up on the shelves of your local health food store.
Mysterious Balls of Goo Are Rolling Onto American Beaches
A salp chain hangs suspended in the open ocean near Bali, Indonesia.
PHOTOGRAPH BY REINHARD DIRSCHERL, ULLSTEIN BILD/GETTY IMAGES
PUBLISHED
Often called "jellyfish eggs" for their superficial resemblance, these creatures are called salps and they're more closely related to people than they are to jellyfish.
In fact, the only thing salps and jellyfish have in common is that both are gelatinous and both float around in the ocean, says Larry Madin, executive vice president and director of research at the Woods Hole Oceanographic Institution in Massachusetts.
Changes in wind direction or water currents will push the barrel-shaped animals on to beaches, which happens with some regularity, says Paul Bologna, director of the marine biology and coastal sciences program at Montclair State University in New Jersey.
That’s what happened in Ocean City, Maryland, on July 11 and 12, and it’s what’s happened up in Cape Cod, where Madin says he’s heard reports of salp strandings this summer.
The good news is, they're entirely harmless, unlike some of the other gelatinous things people have reported seeing on beaches in recent years. A Portuguese man-of-war washed up in Atlantic City, New Jersey, last week and Bologna says last year a number of box jellies were sighted off the New Jersey coast.
A Weird Sex Life
Salps are part of a group called tunicates, says Madin, a tunicate specialist. And members of this group have a kind of primitive backbone, which jellies lack. The animals can also "give birth" to long chains of clones, and recent research finds that they may actually be a weapon against global warming.
Sometimes referred to as "jellyfish eggs," salps are the latest gelatinous animal to wash ashore along the U.S. east coast.
PHOTOGRAPH BY CHRIS COMBS, NATIONAL GEOGRAPHIC
The thumbnail-size salps most commonly sighted on beaches are one of about 50 species which range from Antarctica to just south of the Arctic. Some species can get up to almost a foot (30 centimeters) long.
Part of their life cycle involves asexual budding, where one salp creates a chain of hermaphroditic clones that stay connected. The chains in some species can get up to 50 feet (15 meters) long. Sometimes, Madin says, the salp chain comes out in shapes; one species creates a wheel of salps, while another species organizes its chains into a double helix.
Eventually, the salp chains break apart. All the individuals that are released turn into females containing one egg. Males from a previous generation of salps will fertilize the females, producing an embryo. The "mother" then develops testes and goes on to fertilize the eggs of other nearby salps, all while the embryo continues to grow inside of it. That embryo eventually pops out and grows up to create another chain of clones.
A salp's ability to mate and combine different genetic material keeps populations healthy, says Madin, while their cloning abilities let them reproduce very quickly. (See "Huge Swarm of Gelatinous Sea Creatures Imaged in 3-D.")
A "Weapon" Against Climate Change
Salps' cloning tendencies also let them take advantage of algae blooms. The animals gorge themselves on the algae and pump out chains of salp babies. All that eating also produces large fecal pellets that "sink rapidly, as much as a thousand meters a day," Madin says.
This is a salp's secret weapon against climate change. The algae that they eat uses carbon dioxide from the atmosphere to grow. The salps then eat the algae and all that carbon. When the animals produce their pellets, that carbon sinks to the bottom of the ocean where it's essentially removed from the carbon cycle.
Essentially, salps repackage carbon into big pieces that sink very quickly into the ocean, says Bologna. "It's one way of trying to balance out how much CO2 is in the atmosphere."
Madin is skeptical that the salps will be able to keep up with the increased carbon in the atmosphere, but notes that salps can eat much smaller particles of plankton than animals like crustaceans and copepods. "One thing we see with warming temperatures is that the types of phytoplankton species are changing from larger ones, like diatoms, to smaller ones which we call picoplankton," he explains.
So "salps may have a competitive advantage as the oceans grow warmer," Madin says, because they'll be able to eat the really small plant plankton that will become more common.
Which means we may see more and more of these gelatinous creatures washing up onto beaches in the near future.
Scientists Unravel the Mystery Behind Cotton Candy-like “Hair Ice”
Hair ice -- have you heard of it? The rare ice grows upward, forming fine, hair-like filaments that form a glacial toupee of frost atop rotting wood.
"Hair ice grows mostly during the night and melts again when the sun rises. It's invisible in the snow and inconspicuous in hoarfrost," says biologist Gisela Preuss.
Scientists have now filled in a major gap in our understanding of the ice's formation: the fungus Exidiopsis effusa. When the temperature dips below freezing on humid winter evenings, hair ice springs out of rotting tree branches that house E. effusa.
Upon examining samples of melted hair ice, researchers identified the organic compounds lignin and tannin, metabolic byproducts of fungal activity.
"The action of the fungus is to enable the ice to form thin hairs -- with a diameter of about 0.01 mm -- and to keep this shape over many hours at temperatures close to [freezing]," explains Christian Matzler, a physicist at Switzerland's University of Bern. "Our hypothesis includes that the hairs are stabilized by a recrystallization inhibitor that is provided by the fungus."
Hair ice has been the focus of scientific investigation since 1918; it took nearly a century to understand fully because the phenomenon is so rare.
Tuesday 14 July 2015
Fighting Octopuses Video Is First to Show How They "Talk"
Standing tall, arms spread, changing colors—them's fighting words for anoctopus.
Until recently, scientists thought the ocean dwellers didn't communicate with one another much at all. Rather than sending signals with their skin color and texture, octopuses—mostly solitary, except during mating—were thought to camouflage themselves with it.
But new video evidence suggests at least one kind of octopus—the common Sydney octopus (Octopus tetricus)—sends cues to its rivals about whether it will flee or flight. (Also see "Social Octopus Species Shatters Beliefs About Ocean Dwellers.")
David Scheel, a marine biologist at Alaska Pacific University, and colleagues shot the footage off southeastern Australia—the first evidence that fighting octopuses broadcast their intentions to one another.
Living to Fight Another Day
The common Sydney octopus, also known as the gloomy octopus, were thought to be very independent: When they do come together to mate, the female often eats the male afterward.
So the researchers were surprised that Sydney octopuses at their research site seemed to be interacting regularly.
"The expectation has been that if two octopuses meet, the big one eats the smaller one," says Scheel, who presented the initial findings at a recent Animal Behavior Society meeting in Anchorage, Alaska.
"But if octopuses encounter each other routinely, they can't cannibalize each other all the time."
Instead, it makes sense that the octopuses would need to communicate to either escalate or avoid conflict—which is exactly what the team found. (See "Journey of Octopus Discovery Reveals Them to Be Playful, Curious, Smart.")
Scheel and his colleagues observed a range of aggressive interactions between octopuses—everything from simply reaching out toward another octopus, to chases, to grappling. Of all these incidents, only a fraction were full-blown fights.
To get their point across, octopuses used a suite of dramatic behaviors such as spreading their arms wide, standing tall, raising their mantles—a structure that holds all their organs—like a crest above their eyes, and climbing on top of objects, the team observed. (See beautiful octopus pictures.)
The animals also changed color depending on their behavior: Aggressive octopuses tended to become darker, while fleeing octopuses were much paler.
"If one octopus signals that he's coming over and not going to back down, and the other signals he is going to run away, that can end the interaction," says Scheel.
"Whereas if they both signal that they're not going to back down, those are the [incidents] that tend to escalate."
Fight or Flight
This octopus body language likely occurs in more species, says Christine Huffard, a senior research technician at the Monterey Bay Aquarium Research Institute who was not involved in the new research.
"I would love to see people study this in different octopus species in the wild, but also research the mechanisms behind it," Huffard says. "It's hard to know whether it's an intentional versus a physiological response. For instance, we blush. We don't say, 'Hey, body, tell this person I'm embarrassed.' It's just something that happens." ("Watch: Stealthy Octopus Leaps From Water and Attacks Crab.")
Huffard agrees with Scheel and his colleagues that it's likely the octopuses are signaling to avoid costly battles.
When octopuses fight, the larger one nearly always wins.
"If you know from the beginning that you're probably going to lose or you're not really willing to give up an arm, you might as well tell your opponent that you don't want a fight."
Watch 2 Men Save a Beached Great White Shark
A new video shows the dramatic rescue of a beached great white shark off the coast of Chatham, Mass. on Monday.
The video, posted to YouTube, shows the great white gasping for breath, its tail desperately flipping on the beach, as onlookers watch, concerned. The film then cuts to two men—who have been identifiedas harbormaster Stuart Smith and shark expert Gregory Skomal—who are shown scooping buckets of water and splashing the shark, which at first is unresponsive, then shudders awake to cheers and encouragement. The men then tie a string onto the weakened shark’s tail and connect it to a boat, which pulls the shark into the water.
The men gingerly untie the string from the shark’s tail and guide it into the open water by boat.
“Thirty years ago, they’d want to kill it and now they want to save it,” Smith remembered Skomal saying at the time.
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