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This week on "Our World" ... Rapid population growth in many of the world's poorest countries ... the threat posed by ocean dead zones ... and a convention host city touts the virtues of going green:
HICKENLOOPER: "How do we make sure that we're just addressing everything the most efficient way possible and then making it possible for our citizens to share in that efficiency? It is a great way to actually put money into people's pockets these days."
Those stories, dogs using their noses to help biologists, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."
Population growth in coming decades mainly in poorer countries
An annual report on world population trends says nearly all of the growth is happening in the world's poorest countries.
According to the Washington-based Population Reference Bureau, the world's poorest countries, as a group, have higher birth rates and more young residents when compared with richer, industrialized countries.
Carl Haub is co-author of the group's annual World Population Data Sheet.
HAUB: "More and more, population growth is switching into the poorer countries of the world. And more and more decline in the wealthier countries. So the gap we're having now in population growth is bigger than it's ever been."
For example, Haub compared Italy with the Democratic Republic of the Congo. Today, the nations are roughly the same size, but by 2050, Italy's population is expected to grow only slightly ? from 60 million to 62 million people, while the population of the Congo is projected to almost triple, from 67 million to 189 million. That's largely because Congo's birth rate is more than five times higher than Italy's.
HAUB: "And we noticed that in Italy, there were 568,000 births last year. In Congo, [it's] almost three million. That's a bit of a difference."
By 2050, according to this week's release of the population data sheet, there will be more than 9.3 billion people on Earth, up from 6.7 billion today.
Over the next several decades, many of the richest countries will actually lose population. Those that don't, like the United States, will gain population more as a result of immigration than of higher birth rates.
Population Reference Bureau official Linda Jacobsen says India's population will grow by half, but China, now the world's most populous country, is growing much more slowly.
JACOBSEN: "What this means is that, according to the World Population Data Sheet, in 2050, India will be the most populous country in the world, China will be second, and the United States will be third."
By mid-century, Africa's population will double, to two billion.
In poor countries, a higher birth rate and poor health go hand in hand. In many parts of the world, childbirth is itself a leading cause of death. But co-author Carl Haub notes that from region to region across the globe, there are wide variations in the possibility that a woman will die at some point in her life from complications relating to childbirth.
HAUB: "In the developed countries, about one in 7,300 women are likely (to die) from a pregnancy-related cause. One in 7,300. In eastern Asia, that's one in 1,200. In North Africa, one in 210. South Asia, one in 61. And finally, sub-Saharan Africa, one in 22."
Better medical care obviously improves the odds of a woman surviving pregnancy and childbirth, but so does simply reducing the number of pregnancies she has.
Families with lots of kids may find it difficult to provide enough nutritious food for all. Richard Sholkin of the population group points out that the results of poor nutrition in the first years of life can be charted over a lifetime.SHOLKIN: "An important share of the world's population doesn't get enough food to eat, or enough of the right kinds of food. In young children this often leads to stunting, which means they're especially short for their age. Stunting is related to cognitive deficits, and it's related to lower productivity as adults."
There's a lot more detail, including country-by-country projections at the Population Reference Bureau's website, prb.org, where you can download a copy of the World Population Data Sheet and see what your country is expected to look like, demographically speaking, in 2050.
New guidelines for treating sepsis (blood poisoning)
In the 21st century, infections should be a thing of the past. Antibiotics have been around for decades, now. But bacteria develop resistance to many of our best and newest drugs. And many old infections still kill by the millions.
What we used to call blood poisoning is what doctors now call sepsis. Sepsis occurs when a person has so much bacteria in the blood stream that the body becomes overwhelmed, unable to fight off the infection. As we hear from health reporter Rose Hoban, an international team of researchers has developed a new set of treatment guidelines to replace existing one-size-fits-all recommendations.
HOBAN: Sepsis is a major cause of death throughout the world. But it's hard for doctors to know how many people die from sepsis, because it often occurs as part of another disease, such as AIDS or malaria.
Microbiologist Sharon Peacock studies sepsis at Mahidol University in Thailand. She says established guidelines for treating sepsis often aren't relevant in many parts of the world.
PEACOCK: "There is a lack of resources and necessary infrastructure to provide the level of care that is described in these guidelines. And so throughout low and middle income countries, there is a very, very variable range of medical facilities, and what we would very much like to see is that people start to consider that you don't have to do everything, that you can do what you can in a given setting, get using your available resources."
HOBAN: Peacock worked with doctors and researchers around the world to devise treatment standards that can be used in many different settings ? from places with many resources to those with few. She points out, for example, that many hospitals in developing countries do not have mechanical ventilators to give respiratory support to sepsis patients who are having trouble breathing.
PEACOCK: "In some settings there would be nothing that you could offer. In other settings you may be able to offer supplemental oxygen, so oxygen via a face mask, and, in some settings, quite extreme settings, some patients may be even intubated, and the relatives will actually work to breathe for their relative by squeezing a bag in and out. So that would be a very extreme example."
HOBAN: Peacock says the point of her research and article is to provide guidance so that doctors know what will work best with the tools available to them to help their patients with sepsis.
Her article and guidelines are published in the journal PLoS Medicine. I'm Rose Hoban.
Denver goes green ahead of Democratic Party convention
The U.S. political spotlight will be on Denver, Colorado, this week, where the Democratic Party will be holding its presidential nominating convention. Convention organizers are promising that recycling, carbon offsets, and other strategies will make this the "greenest," most environmentally-friendly national political convention ever. And when our environment reporter, Rosanne Skirble, was in Denver recently, she found a city that wants to be seen as a community that's leading the way toward solutions to climate change.
SKIRBLE: With 1,400 kilometers of bike paths in the metro area, Denver is among the most bike-friendly cities in the United States. That's one reason John Hickenlooper likes to live here.
HICKENLOOPER: "Today is Bike to Work Day. So, like about 35,000 other Denverites, I rode my bike to work today."
SKIRBLE: Hickenlooper, who became mayor of Denver five years ago, wants to keep his city green. Last year, Hickenlooper initiated 'Greenprint Denver,' a five-year citywide plan to reduce global warming emissions by 20 percent.
HICKENLOOPER: "We have got to stay focused and make sure that we are not wasting energy, so Greenprint Denver is to get all the city agencies working together to make sure that every single vehicle is getting maximum gas mileage. How do we make sure that we're just addressing everything the most efficient way possible and then making it possible for our citizens to share in that efficiency? It is a great way to actually put money into people's pockets these days."
SKIRBLE: Greenprint Denver did an inventory of the city's greenhouse gas emissions. Michele Weingarden, who heads the program, says that helped them identify special projects to lower Denver's carbon footprint.
WEINGARDEN: "So Greenprint Denver is working on energy efficiency and renewable energy programs, water conservation, greening homes and businesses, expanding recycling, planting a million trees, and building green."
SKIRBLE: Mayor Hickenlooper says people in the metro area not only understand the problem of climate change, they are committed to solving it. Recently taxpayers voted to expand public transportation by adding nearly 200 kilometers of new light and commuter rail.
HICKENLOOPER: "We went out and passed four-tenths of a cent sales tax over the whole metropolitan region, right, and yet we got every single mayor ? 32 mayors ? Republicans and Democrats, every mayor supported it because we realized we are here for a quality of life. We want to grow, we want a strong economy, but we gotta to do it in a responsible way."
SKIRBLE: In a former warehouse in Denver's historic Lower Downtown district, John Powers runs the Alliance for Sustainable Colorado.
POWERS: "The intention was to create a hub for non-profits, so it was a place to get them to be able to work more efficiently and effectively, and get more per dollar. We also wanted to make it a healthy building. So that is why we made it green."
SKIRBLE: Using off-the-shelf technologies, Powers says the alliance has turned its 1906 building into a model for 21st century energy efficiency.
POWERS: "We've changed out our lights, and we are saving approximately 40 percent. We've done more insulation. So those are some of the changes. We've cut our annual electric consumption from 750,000 kilowatt hours to 480,000 kilowatt hours."
SKIRBLE: The building also has systems in place that drastically reduce water use.
In a tour through the building, Powers points out strategically placed signs in the corridors, in the bathrooms and offices that explain the technologies being used here. He says it's an effort to get consumers to make some changes.
POWERS: "The features are wonderful and important to show people what they can do in their own lives, but actually we use them like honey to attract bees, to show people the value and importance of collaboration in a healthy environment, healthy setting. This is a mission-driven organization in a mission-driven building.
SKIRBLE: Democratic National Convention organizers expect to put on the greenest convention ever, one that will set the standard for future such events. City officials are hoping that visitors and delegates will take home some green ideas ? from the flower planters, recycle bins and bike paths to the transit system, solar arrays and sustainable buildings ? so Denver's green solutions will flourish across the country. Rosanne Skirble, Denver.
Website of the Week features BarackObama.com
Time again for our Website of the Week, when we showcase interesting and innovative online destinations.
As we just heard, the two major U.S. political parties are holding their presidential nominating conventions over the next two weeks, and to help you get to know the candidates, we'll be featuring their websites here on Our World.
Next week, ahead of the Republican convention in St. Paul, we'll introduce you to John McCain's site.
But this week, with the Democrats set to convene in Denver on Monday, we'll give you a look at BarackObama.com
Candidates use their websites to raise money, rally their supporters, and let voters know where they stand. More than ever before, they're doing it now with videos, so you can hear them speaking in public events or in interviews about, for example, the war in Iraq.
OBAMA: "I think that we now understand that this has been probably the biggest foreign policy fiasco in a generation. So what I've said is that we've got to be as responsible and careful getting out as we were careless getting in, but we need to get our troops out of the combat roles that they've been placed in. They should not be refereeing a civil war in Iraq."
On BarackObama.com, you can check out news about the candidate; see how he's appealing to groups such as students, labor union members, and people with disabilities; or listen to his views on the economy or education.
OBAMA: "No one needs to tell me about the importance of education, because I wouldn't be where I am today without it. I didn't come from wealth. I didn't come from power. And my family came from relatively modest means, but they had a good education and they instilled in me a desire for a good education."
The site also includes lavishly produced videos featuring a variety of endorsements, from ordinary Americans to distinguished Harvard law professor Lawrence Tribe.
TRIBE: "He was, all around, the most amazing student that I can remember having in 37 years and thousands of students...."
Learn about one of the two men most likely to be the next U.S. president at BarackObama.com, or get the link to this and more than 200 other Websites of the Week from our site, voanews.com/ourworld.
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You're listening to VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.
Ocean dead zones threaten coastal ecosystems
"Dead zones" are multiplying along the world's coasts. There are now more than 400 areas where the bottom waters have too little oxygen to support life. As we hear from Véronique LaCapra, Scientists say these polluted regions pose the single greatest threat to coastal ecosystems.
LaCAPRA: When nitrogen from agricultural fertilizers and from the burning of fossil fuels gets into coastal waters, it stimulates the growth of algae. When these plants die, they sink to the ocean floor, and are consumed by bacteria and other organisms. The process uses up oxygen, which is normally replenished by water circulating down from the surface.
But marine scientist Robert Diaz says that doesn't happen if the surface and bottom waters can't mix.
DIAZ: "It can be hotter water on top, cooler water on the bottom, or it can be fresher water on top, more salty water on the bottom. When the waters are isolated, bacterial respiration and other animal respiration reduce the water dissolved oxygen in the bottom layer, and create these low oxygen areas that become known as dead zones."
LaCAPRA: "Dead zones" can be one-time events, or they can recur from day to day or year to year. In extreme cases, once oxygen depletion sets in, "dead zones" can persist for years.
This loss of oxygen has major implications for marine life. Diaz ? a professor at the Virginia Institute of Marine Science ? says animals like fish, crabs and shrimp will try to escape oxygen-depleted bottom waters.
DIAZ: "The organisms that are left behind ? clams and worms and things that just can't move, or move very much ? they start to initiate a series of behaviors to survive."
LaCAPRA: Animals that normally stay in the sediment will come out into the water looking for oxygen. They'll stop feeding.
DIAZ: "Then what you what you see is mass mortality of all the organisms that are left behind."
LaCAPRA: In some cases, the drop in oxygen can be so rapid and widespread that even fish can't get away. Off the northwestern coast of the United States, for example, a "dead zone" is killing fish and other marine life in an area of over 3,000 square kilometers.
Other "dead zones" are even bigger.
DIAZ: "The Baltic Sea being the largest, at one time it was estimated at over 100,000 square kilometers, but it's reduced down now to somewhere between 70 and 80 thousand."
LaCAPRA: There are other large "dead zones", as well, including one in the Gulf of Mexico and another in the East China Sea. Globally, Diaz estimates that these oxygen-depleted areas add up to more than a quarter million square kilometers ? an area about the size of Britain or Laos.
Prior to the 1960s, scientists had identified fewer than 50 "dead zones" worldwide. Since then, that number has roughly doubled every decade.
DIAZ: "Now we have well over 400 documented areas around the globe that have some form of low oxygen that is related to human activity."
LaCAPRA: And Diaz expects that even more nutrients will enter coastal waters over the next fifty years.
DIAZ: "So this pattern of increasing dead zones around the world ? and the severity of the dead zones ? is likely to increase until somehow we can control the amount of nutrients getting into our estuaries and rivers and seas."
LaCAPRA: But if we can reduce that amount, says Diaz, we can bring the "dead zones" back to life.
In the 1970s and '80s, fertilizer runoff from agriculture reduced oxygen levels in the Black Sea.
DIAZ: "But with the collapse of the Soviet Union, subsidies were eliminated to a lot of the farmers in the area, and the amount of nitrogen and phosphorus going in to the Black Sea declined by factors of 3 and 4. And over a period of 3 years the Black Sea went from a 40,000 square kilometer dead zone, to zero."
LaCAPRA: Up until now, the vast majority of coastal "dead zones" have been found in the northern hemisphere, where most of the world's population ? and aquatic research ? is concentrated.
But Robert Diaz fears that tropical regions could be among the most sensitive to the effects of human development.
LaCAPRA: Diaz's analysis of global "dead zones" is published in the journal Science. For Our World, I'm Véronique LaCapra.
Dogs trained to help biologists in the field
Finally today, researchers and environmentalists are experimenting with a new method for collecting biological samples in the wild. Guided by a dog ? the sensitive nose of a trained tracking dog, that is ? they're finding everything from rare plants to moose droppings. Brian Mann joined the hunt in New York's Adirondack Mountains.
MANN: It's early, the sun tangled in the alder trees, when we set off on foot down a narrow logging road.
Soon, Heidi Kretser with the Wildlife Conservation Society finds the first evidence that we're not alone.
KRETSER: "These are moose tracks."
MANN: New York's moose population has surged in recent years, to more than 500 animals. Researchers have been tracking moose using airplanes and radio collars.
But today, were tagging along behind a dog, a cheerful black lab mix named Wicket.
Wicket flashes back and forth across the trail, sniffing eagerly. She wears a bright red vest to make her easier to follow, and that tinkling bell is designed to keep her from actually meeting a moose head-on.
Her owner and handler, Aimee Hurt, says using dogs to find biological samples ? everything from plants to rare birds ? isn't new.
HURT: "I think if you talk to a lot of biologists that have been out in the field for decades, 'Oh yeah, my dog figured out that we were looking for, whatever.' And they started honing in on it and helping out. So I really think that dogs have been biologists' partners for a long time."
MANN: Hurt's organization, Working Dogs for Conservation, based in Montana, took the idea one step further, training dogs in much the same way that police train K9 units.
KRETSER: "She is an air-scent dog, which means there's no tracking involved, so her nose isn't to the ground, she's not trying to pick up a moose track. She's just sniffing the air for a whiff of scat."
MANN: Heidi Kretser, with the Wildlife Conservation Society, says moose droppings can tell a lot about why these Clydesdale-sized animals are returning to New York, what they're eating, and how their outsize diets could reshape this forest's mix of trees and undergrowth.
"By understanding the diet, we'll get a better sense of what habitats they might impact long-term, since they eat 40 pounds [18 kgs.] of vegetation a day."
MANN: Wicket leads the team on a long ramble through the radiant lime green forest, and down across a burbling creek.
We see moose sign everywhere ? mule-sized tracks, maple trees stripped of bark. And then Wicket sniffs out her first pile of droppings.
"Whoopee, good girl. Very nice!"
MANN: More poop means better data. So the pellets are trucked away in a plastic bag for the trip back to the lab.
For Wicket, the reward is a few minutes of play. She jumps around, gnawing on a squishy rubber ball.
"Let's get to work!"
MANN: Then the team is off again, with Wicket snuffling happily through the trees. Biologists hope to use the same method to study other wildlife ? from grizzlies to mountain lions.
For The Environment Report, I'm Brian Mann. [This segment © 2008 Environment Report.]
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That's our show for this week. If you'd like to get in touch, email us at firstname.lastname@example.org. Or use the postal address ?
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Support for the Environment Report comes from the Joyce Foundation, the George Gund Foundation, and the Americana Foundation. You can contact them at environmentreport.org.
Rob Sivak edited the show. Eva Nenicka is the technical director.
And this is Art Chimes, inviting you to join us online at voanews.com/ourworld or on your radio next Saturday and Sunday as we check out the latest in science and technology ... in Our World.