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Public Radio's Environmental News Magazine (follow us on Google News)

March 30, 2012

Air Date: March 30, 2012



Limiting Carbon From Future Power Plants

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The Environmental Protection Agency has proposed the first national standards to limit CO2 emissions from new power plants. Eric Schaeffer heads the watchdog group, the Environmental Integrity Project. He tells host Bruce Gellerman that the EPA’s rules have some loopholes but could be a big tool in fighting climate change. (06:25)

Triclosan Safety Questioned

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The antibacterial agent triclosan is found in many consumer products like toothpaste, countertops and children’s toys. A coalition of environmental groups claims the chemical is an endocrine disruptor and toxic to the environment. But the U.S. Food and Drug Administration says there is no evidence of harm. Host Bruce Gellerman talks to Nichelle Harriott from Beyond Pesticides, the group leading the environmental coalition, and Shelly Burgess from the FDA. (05:00)

Africa’s Great Green Wall of Trees / Bobby Bascomb

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Africa is turning to desert. Studies show that as much as two thirds of the continent’s arable land could become desert by 2025 if current trends continue. But a bold initiative to plant a wall of trees 4,300 miles long across the African continent could keep back the sands of the Sahara, improve degraded lands, and help alleviate poverty. Living on Earth’s Bobby Bascomb reports from Senegal. (10:30)

The World’s Largest Wildlife Conservation Area

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Five nations in Africa have come together to create the world’s largest conservation area for wildlife. World Wildlife Fund’s Chris Weaver tells host Bruce Gellerman that the new preserve will allow migratory animals like elephants and rhinos to roam more freely. (06:00)

Big Advances in Testing Chemicals

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Advances in computing are dramatically changing the field of chemical testing. And, as Living on Earth’s Ingrid Lobet reports, one day there may be far less need for scientists to use laboratory animals to test chemicals for health and safety. (06:20)

Satellite Archeology

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Mesopotamia is believed to be the birthplace of civilization, but the extent of human settlement in this area is relatively unknown. Archeologists spend a lot of time scouring the ground for clues, but now some enterprising scientists are looking to the skies for help. Professor Jason Ur of Harvard tells host Bruce Gellerman about turning satellite photos into maps showing ancient cities, and why he digs this new technology. (11:00)

Show Credits and Funders

Show Transcript

HOST: Bruce Gellerman
GUESTS: Eric Schaeffer, Nichelle Harriott, Shelly Burgess, Chris Weaver, Jason Ur
REPORTERS: Bobby Bascomb, Ingrid Lobet.


GELLERMAN: From Public Radio International - it's Living on Earth. I'm Bruce Gellerman. The EPA comes up with emission standards for coal-fired power plants in the future, but do the new proposed regulations make coal history?

SCHAEFFER: It means that you can't build a new coal plant in the U.S. unless you remove a significant amount of the carbon.

GELLERMAN: Coming up, coal gets its lumps from the EPA. Also, Africa’s Great Green Wall, four thousand miles of trees designed to block the sands of the Sahara.


VOICEOVER: In ten to 15 years this will be a forest. The trees will be big and this region will be completely transformed. Already we’re already seeing animals come back that haven’t been here for years, mostly deer and many species of wild bird, even jackal.

GELLERMAN: And Africa’s Great Green Wall could lift many people out of poverty. These stories and more this week on Living on Earth, stick around!


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ANNOUNCER ONE: Support for Living on Earth comes from the National Science Foundation and Stonyfield Farm.

Limiting Carbon From Future Power Plants

Natural gas is cheap and produces fewer emissions, so coal would become a less desirable energy source. The Peabody Coal Company in Northeastern Arizona. (Photo: Lyntha Scott Eiler, DOCUMERICA)

GELLERMAN: From the Jennifer and Ted Stanley Studios in Somerville Massachusetts, it’s Living on Earth. I’m Bruce Gellerman. All futures are uncertain, but now, with the EPA proposing new emission standards for power plants, the future of coal is especially uncertain. Coal is the number one source of our nation’s electricity, but boy, does burning it pollute! It is, by far, the number one source of our climate changing CO2 emissions.

Five years ago the U.S. Supreme Court ruled that the EPA could regulate carbon dioxide as a pollutant, and this past week, that’s just what the agency did. To the disappointment of many, the EPA’s proposed regulations would only affect new coal power-plants, not the 600 currently in use. Still, the new standards would be among the biggest changes in U.S. environmental law ever. During the George W. Bush Administration, Eric Schaeffer was in charge of enforcing the Clean Air act; now he heads the EPA watchdog group, the Environmental Integrity Project.

SCHAEFFER: It's a serious standard. It means that you can’t build a new coal plant in the U.S. unless you remove a significant amount of the carbon, it’s a big deal.

GELLERMAN: Well, the operative word there is “new” coal plants.


Powering an average home creates about 5.5 lbs of CO2 every hour--- the new rule demands only 3 lbs per hour. Four Corners Generating Plant in Arizona. (Photo: Lyntha Scott Eiler, DOCUMERICA)

GELLERMAN: So, this only affects those that are going to be built, although there is this kind of year wiggle room.

SCHAEFFER: Yes, there are a number of exemptions in the rule in an effort to soften the impact and one of those is if you’re already holding a permit to build a new plant, you’ve got a year to get started, and there are about 15 plants in that category. Another exemption, really, is if you’ve got an existing coal plant and you reconstruct or modify that plant to beef up its capacity, make it bigger basically, then you’re not subject to the new standard. And a lot of coal companies do that, a lot of utilities do that, they’ll take an old unit and they’ll refurbish it and boost the capacity so that it comes back to life bigger and stronger than it was. And that kind of remodeling of a plant is exempt.

GELLERMAN: So is there going to be a mad scramble to slide new plants under this new rule?

SCHAEFFER: If you don't already have a permit, it’s too late. So it’s not as though you could read this announcement today and say 'oh, I better run out and get my application in to build a new coal plant.' It takes several years to get a permit. There are about 15 coal plants today that are holding permits, where ground hasn’t broken yet.

GELLERMAN: I was looking at the EPA fact sheet and it says this: Even if there were no standards, no new regulation by the EPA, people still wouldn’t be building coal plants.

SCHAEFFER: I think that’s true, that’s what the economic analysis shows. About three years ago, we were looking at a wave of applications to build coal plants, there were applications going in all across the United State to build very big coal plants. Most of those have fallen by the wayside. Some of them were defeated in permit battles, but most of the collapse in that market for new coal plants came about because gas got cheaper and cheaper, it no longer made sense to build a big coal plant with gas prices so low and renewables are more and more competitive. So, I think the EPA is exactly right that the market for new coal plants is tiny if it exists at all for the next couple of decades.

GELLERMAN: Now, the way this regulation is structured, coal plants can store their emissions underground, carbon capture and storage, and therefore meet the new standard. But my understanding is that there is no commercial carbon capture and storage, and nobody really thinks it’s really going to happen in the next decade or more.

SCHAEFFER: I think that’s right. Companies are just not going to invest a lot of money to bury carbon dioxide from a big coal plant when they can build a gas plant for less money when you get to the full operating costs. I think EPA proposal recognizes that, EPA suggests that carbon capture might be economical if the cost of that technology comes down in about ten years. And they provide a pathway in the bill that lets you take your carbon emissions and average them over 30 years. So you can effectively meet the standard by building a plant that is a little above the standard today, if you agree to install carbon capture within ten years and bring the carbon dioxide emissions down far enough that over the 30-year lifetime of the standard, you’ll hit the number that the EPA wants you to hit.

The EPA’s proposal offers the first nationwide standard regulating carbon emissions from future power plants.

GELLERMAN: But isn’t that pie-in-the-sky, in other words, who would invest in a coal plant and hope that the technology would be there so that they average out over 30 years to meet the standard?

SCHAEFFER: Beats me. The economics aren’t there and the prospect of trying to site a large carbon sequestration plant near everybody’s groundwater where people are going to have questions where the carbon is going and how long it can be safely stored and, you know, what’s it going to do to the water supply. You could imagine what those fights would be like. And again, with gas almost being given away right now, I just don’t see a market for carbon sequestration and I don’t think that’s a very radical view.

GELLERMAN: So, given the economics, given the new standard, is coal as an energy source now DOA? Are we hearing the death knell of coal?

SCHAEFFER: You know, I think that would be melodramatic. Something to remember is that we still have a lot of existing coal plants. As you pointed out, this rule does not apply to existing coal plants, even if those plants are remodeled, reconstructed in a way that makes their emissions greater. And I would expect to see that happen, to continue to happen, at a number of large coal plants. We won’t see new ones, but we’ll see existing plants, the ones that survive, generating more than they do today.

GELLERMAN: Is this standard that the EPA has announced, is this what you were hoping for?

SCHAEFFER: I have seen the Administration and EPA backpedal on some major rules under political pressure and I would not have been surprised to see a weaker standard - not so much because that’s what EPA wanted, but because of internal pressure and the pressure of the election. The fact that they have drawn a line with this proposal, I think that’s a significant step. I’m actually pleasantly surprised that they set a standard for new coal plants - with all its warts and exemptions - that is the kind of standard that you’d want to see if you want to do anything about global warming and get these emissions under a standard.

GELLERMAN: Well, Eric Schaeffer, thanks so much.

SCHAEFFER: Thank you so much, it was a pleasure being with you.

GELERMAN: Eric Schaeffer heads the EPA watchdog group, the Environmental Integrity Project.

Related links:
- EPA Announcement:
- The Environmental Integrity Project

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[MUSIC: Dr. John “Gris Gris Gumbo Ya Ya” from Gris Gris (Atco records 1968).]

Triclosan Safety Questioned

Triclosan is in toothpaste, cutting boards, children’s toys and many other common products. (Photo: Wikimedia Creative Commons)

GELLERMAN: The chemical triclosan can be found in thousands of household products - toothpaste, kids' toys and face creams, computer keyboards, yoga mats and soaps - especially soaps. Tricolosan is in so many products because it kills germs.

Triclosan has been around for 40 years, and for nearly all that time U.S. officials have been investigating the chemical for safety and effectiveness. Now the Canadian government has just declared the antibacterial agent an environmental toxin, and has proposed regulations that would sharply curtail its use in Canada. Nichelle Harriott is with the environmental group Beyond Pesticides. It's leading a coalition of 80 organizations trying to get triclosan banned in the United States.

HARRIOT: Every product that triclosan is in, is essentially washed down the drain and directly goes into the environment. In surface water, it degrades to another chemical, 240CP, which is known under the Clean Water Act as a priority pollutant, which means that EPA is supposed to regulate that chemical. We know that it is probably taken up by plants and by crops that we eat, and we don’t actually know what the effects are because no one is looking at this, yet we are putting this chemical out into the environment.

GELLERMAN: But Canada specifically says that there’s not sufficient evidence to conclude that this is harmful to people.

HARRIOT: I did see that and that is pretty shocking, but a lot of work that we have done have shown that there are some serious human health effects that we need to take a look at. So, we know that triclosan is an endocrine disruptor. I mean, it impacts our hormones and so if we have this chemical out there in the environment, this is a concern, because it may accumulate up the food chain, we may be ingesting this chemical unbeknownst to us, so what are we doing to our bodies? Triclosan has been found in urine, it has been found in breast milk, it has been found in umbilical cord blood.

GELLERMAN: I know there have been concerns about this antibiotic chemical that is that it could create resistance to drugs that we have to fight bacteria, what is the evidence that this is actually happening?

HARRIOT: Well, there is some preliminary evidence that bacteria exposed to triclosan eventually become resistant to triclosan. And once resistant to triclosan, they may have cross-resistance to other antibiotics, then there is a serious public health concern.

GELLERMAN: As I understand, when triclosan is combined with cholorine, which is in many water supplies, it forms chloroform!

HARRIOT: Yes, there was one study that indicated that. And of course, that waves a lot of red flags, if you’re brushing your teeth, and a lot of toothpaste contains triclosan, are you being exposed to chloroform through the chlorine in the tap water? And chloroform is very toxic, you know, it’s not something that you want to be inhaling. And our regulatory system tends to be more reactionary than precautionary, and so we do allow chemicals into the environment without sufficient human and environmental health overview. So we’re now retroactively trying to do something about this.

GELLERMAN: Nichelle Harriot is with the group Beyond Pesticides. In the U.S., the EPA regulates triclosan as a pesticide; the FDA looks into its uses in foods and drugs. Shelly Burgess is a spokesperson with the FDA.

BURGESS: Triclosan is currently not known to be hazardous to humans, and, we are engaged in ongoing scientific and regulatory review of the safety of triclosan in FDA regulated products. And what consumers should know is that we don't have sufficient safety evidence to recommend changing consumer use of products that contain triclosan at this time.

GELLERMAN: Does the FDA have any evidence to suggest that triclosan in antibacterial soaps provides a benefit, in terms of health, to the user?

BURGESS: What I can say is that we don’t currently limit the concentration of triclosan in over-the-counter consumer products, such as consumer antibacterial soaps. And this is because FDA’s view of the safety and effectiveness of triclosan is ongoing.

GELLERMAN: But I’m reading from a paper that was presented by the FDA to the public two years ago and it says: “At this time the Agency does not have evidence that triclosan in antibacterial soaps and body washes provides any benefits over washing with regular soap in water.” That’s from the FDA, that’s your agency!

BURGESS: That’s correct. That’s correct.

GELLERMAN: Then why is it being sold?

BURGESS: Well, again, we’re engaged in ongoing scientific and regulatory review with the safety of triclosan.

GELLERMAN: When does your review end, do you have a date?

BURGESS: Well, we’re going to publish those findings later in 2012, in the winter of 2012.

GELLERMAN: That’s FDA spokesperson Shelly Burgess. You can learn more about Canada’s proposal that would declare triclosan an environmental toxin and find the latest scientific studies at our web site: loe dot org.

[MUSIC: The Echocentrics “We Need A Resolution” from Echoland: A tribute To Timbaland (Ubiquity Records 2011).]

GELLERMAN: Just ahead, Africa's Great Green Wall, and why national borders and fences make bad neighbors for migrating animals. Keep listening to Living on Earth!

Related links:
- Beyond Pesticides
- Triclosan: What Consumers Should Know
- Congressmen Markey wants to end the sale of triclosan
- The EPA's Research on Triclosan

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[CUTAWAY MUSIC: Nitty Gritty Dirt band with Earl Scruggs: “Nashville Blues” from the Essential Earl Scruggs (Capitol Records 1972)

Africa’s Great Green Wall of Trees

Women plant and take care of a dozen different vegetables in their gardens. (Photo: Bobby Bascomb)

GELLERMAN: It's Living on Earth. I'm Bruce Gellerman. Now to the West African nation of Senegal where an audacious and ambitious project is underway to create a vast forest across the African continent. It’s known as the Great Green Wall. The idea is to plant 43 hundred miles of trees through 11 African nations, from coast to coast.

The Senegalese government hopes the Great Green Wall will stop the advance of the Sahara Desert southward, but as Living on Earth’s Bobby Bascomb reports, others see it as a way of alleviating poverty.


BASCOMB: Horses pull wooden carts alongside cars on the main streets of Dakar, the capital of Senegal. Dakar sticks out into the Atlantic Ocean on a peninsula. And while it’s at least a thousand miles to the Sahara desert, the air today is thick with sand. It’s the worst sand storm in a year.


VOICEOVER: The rainy season is becoming shorter, it used to start in July or August, now it doesn’t start until September. The climate is definitely changing.

BASCOMB: Papa Sarr says shifting seasons and climate change could make these sand storms more common but he believes there is a solution. Sarr is the technical director for the Great Green Wall in Senegal. The goal of the project here is to plant two million acres of trees. It’s part of a larger initiative to plant a nine mile wide wall of trees, across the African continent. African leaders hope the trees will trap the sands of the Sahara.


VOICEOVER: We are convinced that once we start to plant the wall of trees, dust will decrease in Dakar.


BASCOMB: The paved roads of Dakar give way to red sand paths.

SARR: We are going to Widou, Widou Chigoli.

BASCOMB: Black and white goats meander in front of our four-wheel drive. [CAR HORN] This is the Sahel, a dry savanna transition zone between the equatorial jungles in the south and the Sahara to the north. Flat-topped acacia trees dot the sandy landscape. They are virtually the only vegetation in a region where the dry season can last up to ten months.


BASCOMB: Four hours later we arrive near the village of Widou. Twelve thousand acres of the Great Green Wall have already been planted here. These acacias are just four years old, waist high and thorny. The trees are surrounded by a firewall, an area without vegetation that would stop a fire in the surrounding Sahel from entering the planted parcel. A metal fence keeps out tree-eating goats.


BASCOMB: Papa Sarr leads the way through the fence, to inspect this small section of Senegal’s Great Green Wall. He says the trees here have been chosen carefully.


VOICEOVER: When we design a parcel we look at the local trees and see what can best grow there, we try to copy nature. In total we planted seven different species of acacia trees. We plant about two million trees each year.

It may not look impressive now but the Senegalese government hopes trees like this will soon grow into a forest. (Photo: Bobby Bascomb)

BASCOMB: The window for planting trees is short. It must be done during the rainy season, when laborers work long days to plant acacia saplings in the sand along with animal manure for fertilizer.


VOICEOVER: This is Acacia nilotica. It produces Arabic gum used in local medicine and a fruit that can be eaten by animals.

BASCOMB: For the project to succeed it was crucial to plant trees that would also provide benefits for people living here.


BASCOMB: The government hopes the village of Widou will serve as a model for the rest of the Great Green Wall in Senegal. It has big plans for planting more trees but this is also a development project, aimed at helping rural people.


BASCOMB: The Peuhl are the dominant ethnic group in the Senegalese Sahel. Extremely tall and lean, they wear long flowing robes of emerald green and sapphire blue. They look like jewels against the rust colored sand and brown dry grass. Traditionally nomadic, the Peuhl are now helping tend to the trees and gardens. One day a week, women in the area volunteer to help care for gardens full of carrots, cabbages, tomatoes, even watermelon. On this day a group of women, including Guncier Yarati, is using the sides of their flip flops to mound the sandy soil around potato plants.

Women mound the dry dusty soil around their potato plants (Photo: Bobby Bascomb)



VOICEOVER: I like working here. I like working with my friends, we laugh and play while we work but what’s really great is that we have more diverse vegetables. We eat the vegetables and can sell them in the market as well.

BASCOMB: The closest market is about 30 miles away and before the gardens came along it was a day’s trek in a horse drawn cart to get fresh vegetables.


BASCOMB: Most of the gardens are watered using drip irrigation. A hose with holes delivers just the right amount of water to each plant to minimize evaporation loss, but some plants are watered by hand.


Mornings are busy around the well in Widou. People travel miles to get water for their animals and fill containers to take home. (Photo: Bobby Bascomb)

BASCOMB: The women dip large plastic cans into a basin filled with water from a nearby well. Nime Sumaso pours her jug of water over some carrots.


VOICEOVER: When people came from Dakar and showed us that they could plant vegetables in their center, we saw that it was a way to help women in the community so we knew the Great Green Wall project was important for us.

BASCOMB: It’s exactly that kind of community support that the government is hoping to garner. While women here mostly see benefits of the project in their gardens, the men have a different perspective.


The cows in Widou gather around a water trough to drink. (Photo: Mark Fabian)

BASCOMB: In the early morning white hump-backed cows with giant horns gather around the water troughs. The Peuhl depend on their large herds of cows and goats for subsistence, and livestock need a lot of water. French colonizers built water wells every 20 miles in this region. In an area that gets as little as six inches of rain each year, water is life.


BASCOMB: Scientists say the trees of the Great Green Wall will improve rainfall and recharge the water table. That pleases Alfaca, a local herdsman.


VOICEOVER: Planting trees is good for us. Those trees can bring water and water is our future. Water can solve our problem. We are praying for this project to continue.

BASCOMB: Roughly 40 percent of Africa is affected by desertification, where non-desert land turns to desert. The United Nations says two thirds of Africa’s arable land could be lost by 2025 if the desertification trend continues.

Everyone involved in the Great Green Wall agrees that the end goal is to help rural communities. But opinions vary on how the project will do that. African leaders envision the Great Green Wall as a literal wall of trees to keep back the desert. That’s what was proposed by the president of Nigeria, Olusegun Obasanjo, when he came up with the idea in 2005. But scientists and development agencies see it more as a metaphorical wall, a mosaic of different projects to alleviate poverty and improve degraded lands.

SINNASSAMY: Sustainable management of natural resources with the aim of reducing poverty - this is really our goal for this program.

Living on Earth’s Bobby Bascomb interviews a local herdsman called Alfaca. (Photo: Mark Fabian)

BASCOMB: Jean-Marc Sinnassamy is a program officer with the Global Environment Facility, one of the funders of the Great Green Wall. SINNASSAMY: We do not finance a tree planting initiative. It’s more related to agriculture, rural development, food security and sustainable land management than planting trees.

BASCOMB: The Great Green Wall has received 108 million dollars from Sinnassamy’s Global Environment Facility and another 1.8 billion dollars from the World Bank. The 11 countries involved with the project are committed to making progress but there are many challenges; abject poverty, shifting seasons and political instability are top among them. The entire region is in the middle of a food crisis. The United Nations Food Program estimates that as many as 11 million people in the Sahel do not have enough to eat. And Mali recently had a military coup.

Senegal is currently the furthest along with the Great Green Wall. They’ve planted roughly 50,000 acres of trees in addition to protecting existing trees. While it’s been successful so far in Senegal, not everyone believes that it can work across the entire Sahel region. Gray Tappan is a geographer with the United States Geological Survey.

TAPPAN: There’s been a long history of one failure after another in, you know, external projects that come in and try to plant trees.

BASCOMB: He says a better model can be found in Niger. Historically farmers there removed any trees or bushes that sprouted up in their fields. But following a devastating drought in the 1980s, farmers decided to allow the natural vegetation to grow and planted food crops around it. The result was a surplus of food and 12 million acres of trees, an area the size of Costa Rica. Tappan has spent 30 years working in the region and was shocked by the transformation.

TAPPAN: In about 2006 we did a big field trip across Niger and were just blown away by the vastness of this re-greening.

BASCOMB: Tappan says that type of natural regeneration is much more likely to succeed than planting trees. But political leaders in Senegal are committed to their vision. Djibo Leyti Ka is the minister of the environment. He’s in charge of the Great Green Wall project for the entire country. [KA SPEAKING IN FRENCH]

VOICEOVER: We have a lot of desert from Senegal to Djibouti, 4,000 miles long. A wall of trees will stop the wind.

BASCOMB: And for critics? scientists who say planting a wall of trees isn’t practical? [KA SPEAKING IN FRENCH]

VOICEOVER: They are crazy! You saw it, you are witness that the dust is coming. The sand is going to cover us all and we need to stop it. There are many, many environmental projects in Senegal but this is the most important. This one will help men, women and children in the future. [WIND SOUNDS, WALKING]

BASCOMB: Back at the Great Green Wall near Widou, Papa Sarr stops to take in the work they’ve done so far. The waist high trees are just four years old now but he expects big things from them. [SARR SPEAKING IN FRENCH]

VOICEOVER: In ten to 15 years this will be a forest. The trees will be big and this region will be completely transformed. We are already seeing animals come back that haven’t been here for years. Mostly deer and many species of wild bird, even jackal.


BASCOMB: It’s unclear if the newly elected president of Senegal, Macky Sall, will have as strong a commitment to the Great Green Wall as his predecessor. But for the people living here, tending their cows and watering the garden, and hoping the rains will come, the Great Green Wall holds great potential for positive change in Senegal and this region of Africa, for generations to come.


BASCOMB: For Living on Earth, I’m Bobby Bascomb in Widou, Senegal.

GELLERMAN: Our story about Africa's Great Green Wall was made possible with support from the Pulitzer Center on Crisis Reporting and produced with the help of Mark Fabian. Bobby Bascomb took lots of photos on her journey around Senegal. For a slide show visit our website www dot loe dot org.

Related links:
- Pulitzer Center on Crisis Reporting
- Read Bobby Bascomb’s blog from Senegal
- The Global Environment Facility on the Great Green Wall
- Scientific American on the Great Green Wall

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The World’s Largest Wildlife Conservation Area

Victoria Falls in Zambezi will be inside the conservation area. (Wikipedia Commons)

GELLERMAN: Well, from Senegal we now head south to what will soon be the largest wildlife conservation area in the world. Five nations in Southern Africa, Angola, Botswana, Namibia, Zambia and Zimbabwe, recently agreed to create the reserve, roughly the size of California, by connecting existing conservation zones. It seems when it comes to protecting animals, especially those that migrate, the whole is far greater than the sum of its parts. Chris Weaver is the Namibia director with the World Wildlife Fund.

WEAVER: You have animals that historically move between these five countries on a seasonal migration basis but due to a number of borders that were created through colonial governments - they’re rather fictitious borders, and then war in Angola for two decades - we ended up in a situation where the migration corridors were closed off. For example, Africa’s largest elephant herd of almost 250,000 elephants, has been bottled up in Botswana for decades.

GELLERMAN: So you’re physically going to remove fences?

WEAVER: Well, some of it has already been done. The plans are to remove another hundred kilometers of fences between Botswana and Namibia, but also the plans are to remove a lot of mines that were put into southeast Angola during the war, making that area a much more wildlife friendly area.

GELLERMAN: So there have been mines there, from the war? This long?

WEAVER: Yeah. There were roughly two million mines in Angola from the war, from 1975 to around 2001.

GELLERMAN: So you’ve got around half of the elephants on the African continent in this five nation area, what other animals are there?

WEAVER: We’ve got pretty much all of the more charismatic species that you see in southern Africa. The big five, which is: elephants, lion, leopard, rhino and buffalo, and then we have other species like eland, kudu, and we’ve got oryx. And then water species would be animals like crocodiles and hippo, so there’s quite an attractive mix of wildlife from a tourism perspective.

A lion hunting in what's now part of the world’s largest wildlife conservation area. (Photo: FlickrCC/ 14 Rebecca 1)

GELLERMAN: So what is the tangible benefit to the animals? Okay, so they can go back and forth across these international borders, how does that help them?

WEAVER: Well, most of this is what we’d call a semi-arid type habitat and animals need to follow the rains and move through areas. During the dry season they need to go to where there is water along the rivers. And during the wet seasons, they need to move away from the rivers so that they can get grazing and browse for their food. So it’s quite critical, that, if you want your optimal populations to recover in these areas, so that they have the habitat and the range to expand and move on a seasonal basis.

GELLERMAN: What about the people living in this region? How does this conservation area, this new conservation area, affect them?

WEAVER: Well, in the past, communities were never allowed to benefit from wildlife. And as a result, if they used wildlife for meat, for example, it was considered poaching, and people were arrested and put in jail. So people were being asked to live with the wildlife, dangerous species, like elephants, lions and leopards, but never allowed to benefit from it. So as a result, there was heavy poaching and there was actual resistance to living with it.

Migratory elephants like these in Botswana will benefit greatly from the creation of the Kavango Zambezi Transfrontier Conservation Area. (Photo: FlickrCC/Dietmar Temps)

Now, what happened in southern Africa over the last 20 years is that governments realized that if communities were going to live with wildlife, they have to benefit from it. So they passed policies that said: if you form a recognized conservation management unit, such as a trust in Botswana or conservancy in Namibia, then you get the rights to the benefits to the wildlife as long as you responsibly manage them.

And that’s exactly what has happened in Namibia and Botswana. Namibia, for example, in 2010, the communities gained six million dollars in benefits from wildlife, there are about 1,700 full-time jobs and about 8,000 seasonal jobs that have been created through the conservancy movement, which created a lot of incentive for people to live with wildlife now.

GELLERMAN: Chris, can this model work in other parts of Africa do you think?

WEAVER: There are, I think it’s around 20-25 of these trans-boundary initiatives in southern Africa - they are all in a formative stage. I would say that some struggle much more than others because many have been very top-down with little thought being put into how do you involve the local community and build capacity at the ground level to make it real. And that’s one of the real advantages of KAZA, you do have that capacity on the ground in at least three of the five countries.

GELLERMAN: Could this actually have the effect of bringing peace to this area, to stabilizing borders, to stabilizing the nations?

WEAVER: This is actually one of the silver linings. Most people, when they think of conservation and wildlife, they think of biodiversity and their love for animals, but what conservation can do in this case is that it can create stability between five governments that haven’t worked that closely in the past and create a common vision and a cohesiveness in attainment of that vision over time, which in turn helps regional stability in southern Africa.

GELLERMAN: Well, Chris Weaver, thank you so very much.

WEAVER: Well, thank you, and thank you for showing interest in our program down here.

[MUSIC: Youssou N’Dour “Africa Remembers” from Eyes Open (Columbia Records 1992).]

GELLERMAN: Chris Weaver is Namibia director with the World Wildlife Fund.


GELLERMAN: Coming up, great advances in computing change the way we test chemicals and see the ancient world. Stay tuned to Living on Earth!

Related link:
Kavango Zambezi Transfrontier Conservation Area

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ANNOUNCER ONE: Support for Living on Earth comes from the Grantham Foundation for the Protection of the Environment, supporting strategic communications and collaboration in solving the world's most pressing environmental problems, the Gordon and Betty Moore Foundation, and Gilman Ordway - for coverage of conservation and environmental change. This is Living on Earth on PRI, Public Radio International.

[CUTAWAY MUSIC: Earl Scruggs: Peking Fling” from The Essential Earl Scruggs (Capitol records 1972)

Big Advances in Testing Chemicals

Nuclei are blue and a protein called kinase C involved in cell division and tumor genesis is green in this image made using Vala Sciences software.

GELLERMAN: It's Living on Earth, I'm Bruce Gellerman.When scientist test things in vivo, they use living organisms. When they test in vitro, they use test tubes and culture dishes. Now comes the new technique scientists call in silica. It’s just one of the new ways researchers are using computers to find out more about chemicals. Living on Earth’s Ingrid Lobet reports.


LOBET: At Vala Sciences in San Diego, a machine takes pictures of cells that have undergone experiments where they’re exposed to different chemicals. But no one will ever look at these pictures. Instead, they’ll be analyzed by a computer. James Evans is director of automated technology at Vala.

EVANS: We get much higher levels of information from each experiment we do because we collect images and then those images are quantified and we extract lots of numbers from those images.

LOBET: This machine acts as microscope, camera and data-cruncher, all in one. And it’s one example of the way computers are yielding immense amounts of useful scientific information about chemicals.

EVANS: These systems are collecting images 24-7. So we end up with terabytes and terabytes of images.

LOBET: The Environmental Protection Agency recognized the advances in computing and created a National Center for Computational Toxicology. Right away founding director Bob Kavlock found there was catch-up to do. The data from many important older studies done on animals were in pdf format or on microfiche, not searchable.

James Evans and Pat McDonough of Vala Sciences in San Diego. (Vala Sciences)

KAVLOCK: We sent someone up there to Washington for three weeks and they just scrubbed the file cabinets of data. We spent the next two years extracting that into a database we could use. We wound up inputting about 6,000 reports.

LOBET: Now those studies can be searched. And that enables a next step: computers can use that base of data to begin to predict how chemical compounds will work.

KAVLOCK: What we basically do now is we study what chemicals do and we have a whole series of “whats” that we’re concerned about. We’re concerned do they cause birth defects, do they cause nervous systems damage, do they cause effects on reproduction? Do they cause cancer? So we get pretty good at knowing what the chemical might do, but we don’t know how it does it.

LOBET: Researchers have been focusing on the how, discovering the sequences of reactions chemicals set in motion within the body. As scientists understand these sequences or webs better, they are building computer models, simulations, of how cells work, and actually begin to do experiments in the computer, or ‘in silica.’ Researchers are beginning to build virtual tissues.

KAVLOCK: And so in our research program here we’ve got the virtual liver which is trying to develop a model of the functional liver and we have one on the virtual embryo which is trying to look at the developing processes that happen during fetal development.

ANASTAS: It is providing just treasure troves of data, more rapidly and in greater quantity than ever imagined before.

LOBET: Paul Anastas is considered the father of green chemistry and teaches at Yale. He’s also enthusiastic about these advances in what’s called computational toxicology or predictive toxicology.

Software created at Vala Sciences in San Diego captures the effects of chemicals on cells. Here the imager locates cell nuclei. (Photo: CREDIT)

ANASTAS: If you understand the molecular basis of hazard, if you understand what the fundamental chemical properties are that make a substance bioavailable, made it be able to get into your body, if you understand the molecular mechanisms that allow it to have a toxic effect, how it bound to particular receptor, then that is giving you rules on how you design a molecule so that it can't get into your body, so it can't cross particular biological membranes, so that it can't bind to particular receptor and therefore make it less toxic.

LOBET: Chemists are integrating this predictive ability into their design of new chemicals. But there’s still a gaping hole in knowledge of how existing chemicals work. An old pesticide may be known to cause nerve damage. But we often don’t know whether it upsets subtle balances in immunity. Here, faster testing, aided by computers, offers hope.


LOBET: Back at Vala Sciences in San Diego a robotic arm deposits tiny droplets of a chemical into minute compartments, one millimeter square. In the compartments are human fat cells saved from someone who underwent liposuction. The fat cells are then exposed to a chemical. What is this chemical? Pat McDonough, VP of Biology can’t tell you that.

McDONOUGH: The EPA gives us compounds but they don’t tell us what they are. We can’t bias our results in any way because we don’t know what the compounds are expected to do.

LOBET: The machine is able to simultaneously test the mystery chemical on the fat cells at six different concentrations. Three hundred eighty four experiments every half hour.

McDONOUGH: We expose the cells to hundreds of different compounds in different samples.

LOBET: After the cells are exposed and possibly changed by the chemical, an imager takes pictures of what’s happening in every compartment. There are images that show only the fat cells’ nuclei, or proteins holding the cells together. Again Pat Mcdonough.

McDONOUGH: We can also look for lipid droplets, that correspond to obesity and see whether our test compounds are altering those.

LOBET: Tests like these are shedding new light on chemicals, especially pesticides, that have been with us for years. Animal testing is still considered the gold standard. But computers are digesting data from animal studies, cell studies and digital research with unprecedented efficiency, creating the ability to predict what compounds, old and new, shouldn’t be on the market.


LOBET: For Living On Earth, I’m Ingrid Lobet.

Related links:
- National Center for Computational Toxicology (EPA)
- American Society for Cellular and Computational Toxicology
- Environmental Bioinformatics and Computational Toxicology Center
- High Throughput Screening company in San Diego

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[MUSIC: Brian Auger “Ghost Town” from Looking In The Eye Of The World (Ghost Town Records 2003).]

Satellite Archeology

The ancient settlement of Tell Brak. (Photo: Jason Ur)

GELLERMAN: Half the world’s population lives in cities, and by 2050 it’s predicted that 70 percent of us will be urban dwellers. But cities aren’t new; in fact, they’re ancient.

[MUSIC: Michael Levy “Hurrian Hymn (Ancient Mesopotamian Musical Fragment c1400) from Ancient Landscapes (Michael Levy Music 2011).]

GELLERMAN: Music from Mesopotamia. It’s here, in the cradle of civilization, that urban societies first emerged, 6000 years ago. Mesopotamia, the land between two rivers, the Euphrates and the Tigris, stretches from what is modern day Southern Turkey, through Northern Syria and Iraq.

Archeologists aren’t sure why cities first formed, or how many there were, but thanks to a new technique developed by Harvard professor Jason Ur and his college Bjoern Menze from MIT, scientists now have much faster way to identify the tell tale signs of ancient urban societies. Jason Ur says now, in addition to archeologists putting muddy boots on the ground, they can scan satellite images from space.

Brak Classifier, maps showing where people lived, and where artifacts were collected. (Photo: Jason Ur)

UR: I spent two months walking around 125 square kilometers of an area around a Bronze Age city, in northeastern Syria, and I found 60 sites.

GELLERMAN: And using your new technique, your satellite technique, how many did you find?

UR: Well, we found 14,000 places of potential interest, which we could narrow down to around 9,500 relatively reliable places and this was done on computers overnight.

GELLERMAN: Now, satellite imagery has been around for a long time, so what do you bring that’s new to this endeavor?

UR: Well, the traditional way is to get out and start walking. We look for surface manifestations of places where people might have lived, and usually this is in the form of broken pottery, they survive very well and they end up on the surface so we can find places of concentrations of broken artifacts.

GELLERMAN: Slow methods.

UR: Very slow. Today we have systemized this. We are training computers to do this for us, they are much more objective than we are. And then this computer program that I have developed with my colleague Bjoern Menze at MIT, his algorithm then does this in an automated fashion, letting computers do our job for us.

GELLERMAN: Well, let’s look, you’ve brought some images on your computer here. What is this image here? It looks like an abstract piece of art - black and white and red!

UR: What you’re seeing here as red, represents the near-infrared band of the visible spectrum; not something that our eyes can normally see. That’s one of the real powerful aspects of what we’ve attempted to do here is that we can see well beyond what the human eye can see into the near infrared and infrared wavelengths of light which are much too large for our own eyes.

GELLERMAN: So this one looks like, almost like an amoeba, an orange amoeba!

UR: Well, you’re looking at a major early city called Tell Brak. I’ve argued that this is one of the world’s first cities, if not the world’s first city, today in northeastern Syria. The area that you’re seeing that looks like an amoeba is of a high probability of ancient settlement. What we’re really seeing here is soils that have been changed by human occupation. I find this particular image of this particular place to be especially compelling because a second image that I can show you here represents the density of surface artifacts, which I collected over four seasons of walking back and forth across this place and they match precisely.

GELLERMAN: So the idea here is you take empirical studies from on the ground, what you found, and then you say: Okay satellite and algorithm, look at this image, remember this image and compare that to this other new images and see if there’s evidence of an urban settlement.

UR: That’s exactly the process. So if I give it a good set of places that I am 100 percent certain are ancient places, this algorithm can then develop a very precise understanding of what are the wavelengths that represent an ancient place, in this case the soils that human activity produce, that’s really what it’s seeing, and then it can then go find those in other places.

GELLERMAN: Tell me about Tell Brak - what kind of place was it besides just a pile of mud and brick at this point?

Settlement Mounds. (Photo: Jason Ur)

UR: In the past, it was a thriving, very early city. But what our method has shown is there were outlying neighborhoods around them that were spatially separate. They were not up against each other such as what we think of when we think of urban neighborhoods. But what we find is that with time they grow together. And this is very interesting, why initially were there distance between these different parts of the settlement and what overcame this potential reluctance for these groups to come together through time.

GELLERMAN: What do you think?

UR: Well, this is the great question! What we suspect is that there was that initial pull to bring people into a place like Tell Brak, that we don't quite understand. But I would probably say that it wasn’t top down. It was probably something that brought people in under their own volition rather than a central king or ruler compelling people to come in. If I had to guess, I would guess that through time, various institutions developed that could allow people to be more closer together. Maybe these were religious institutions, maybe these were political institutions, that’s something that requires more than satellites.

GELLERMAN: These people - tell me a little bit about the people that might have lived in these ancient cities.

UR: The majority of people living in early cities were farmers and herders. They were concerned with very basic elements of sustaining themselves. When we think of cities today, these cities are homes of the elite, the political elite, great corporations, cities are homes of consumers and producers live out on farms elsewhere. The earliest cities were almost certainly homes of the producers as well.

GELLERMAN: Tell. What does tell mean?

UR: This is a word in Arabic and Hebrew that refers to a ruin. And we don't think of archeological sites as being 'up', we think of them as 'down', you have to dig to get into them. But in fact, in the Middle East, archeological sites stand out. And this is because people build their houses using a mud-brick, and mud-brick houses don’t last very long. After about 50 years you can no longer patch it up, you need to knock it down and start over. So you level your old house, you build your new house on top of it, and through time, your settlement goes up and up.

Dr. Ur in the Living on Earth studio. (Photo: Jessica Ilyse Kurn)

GELLERMAN: So over time these cities literally built on top of themselves, or their predecessors or their ancestors.

UR: This is particularly interesting because people in the past chose to continuously reoccupy exactly the same place. And this doesn’t necessarily make sense. Because, as you go higher and higher, you’re getting yourself further and further from things like your fields and, most critically, from water. And this is what’s interesting, why did some of these places become so important that people would continue to live there even as they were putting themselves at a disadvantage in doing so?

GELLERMAN: You’ve got a hypothesis?

UR: Well, we know that cities were the homes of gods. We think that probably it was, it could have been a cosmological reason, or it could have been political power, in this case we really have to do excavation rather than looking at satellites to answer questions like this.

GELLERMAN: Did you find any cuneiform evidence? Written evidence, since these people were basically the first to use written language, I suppose.

UR: Yes. In this region, we have the origins of writing. And it’s very closely associated with the states and early kingship. However, it post-dates, writing post-dates, the earliest cities, so clearly urbanism as phenomenon was something that didn’t require this sort of administration or book keeping, and probably this is a result of urbanization but not the cause of it.

GELLERMAN: So, urbanization is a very natural process, a very human process, you know, people left upon their own devices will come together?

UR: That seems to be what I take from this particular Mesopotamian case study. I think in a lot of cases, we have a tendency to see governments as behind a lot of these processes. Especially in the past, we see things like the famous mythical king Gilgamesh, who claims to have built the great early city of Uruk. He brought this about through his own kind of charisma and political will.

Probably this is a later understanding of how these places came about, and in fact, it was probably more of what we could call an emergent phenomenon, people acting under their own motivations, but the aggregate of these actions results in something that might look very planned. And here I see a lot of parallels with the intelligent design movement where large complex things can only be the result of some central planner, that certainly isn’t the case with ancient cities.

GELLERMAN: What’s interesting to me is that these urban centers existed for thousands of years and then, they’re gone, most of them. What happened?

UR: Well, there is no single answer. There has been a big attempt in recent years to attribute this to climatic change, this is something obviously that we’re all very concerned about today and we think about this in the past. It may be that in some cases some of these cities simply over extended themselves. Places got simply too large for the existing agricultural technologies. And sometimes when these are excavated, we find that they have been burned. Archeologists love burned cities, because cities that were destroyed, there’s a lot to find there.

GELLERMAN: So probably war?

UR: In some cases. The past was a violent place. Certainly the 20th century AD does not have a monopoly on violence, that’s certainly the case.

GELLERMAN: What now for you? What do you do with all this data from your algorithm?

UR: Well, obviously it’s of academic interest. But there are other aspects of this. We can take this incredible map of settlement, and we can take this to antiquities officials, in this case in Syria, and we can say: Here’s what you have that you might want to protect. This is the past of the Syrian people, but it’s also the world’s past, and this needs to be protected.

GELLERMAN: In the current fighting that’s going on, the war that’s in Syria, are you afraid that some of these areas will be destroyed?

UR: Well, this is always a concern, how the past falls victim to modern political activities. A larger concern in the case of Syria right now, are the museums. We all saw what happened in Baghdad in 2003, will this happen again? I hope that lessons will have been learned. But this is something to bear in all places that have become politically destabilized.

GELLERMAN: Before we go Professor, I’ve gotta ask you about your name, Ur. UR, the ancient city of Ur, that was part of the area that we are talking about, it was Mesopotamia right?

UR: Certainly, yes.


UR: Well, I’ve been accused of having a stage name, uh, but in fact, this is a perfectly good Hungarian name. How I ended up as a Mesopotamian archeologist with this name could be subconscious, I would guess, but I was very close to becoming a Mayanist, which would have meant that this name would have been meaningless.

GELLERMAN: (Laughs.) Well, Professor Ur, thank you for coming in.

UR: Oh Bruce it was my pleasure!

GELLERMAN: Jason Ur teaches urban archeology at Harvard University.

[MUSIC: Michael Levy “Hurrian Hymn (Ancient Mesopotamian Musical Fragment c1400) from Ancient Landscapes (Michael Levy Music 2011).]

GELLERMAN: On the next Living on Earth, too much of a very good thing on the farm has doctors very worried:

MORRIS: Antibiotics are wonderful things. It is frustrating, it is a little bit scary, to watch the gradual increase in problems with resistance.

GELLERMAN: Reining in the use of antibiotics in agriculture, next time on Living on Earth.

Related link:
Jason Ur’s website

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GELLERMAN: Living on Earth is produced by the World Media Foundation. Our crew includes Eileen Bolinsky, Jessica Ilyse Kurn, Helen Palmer, and Ike Sriskandarajah, with help from Sarah Calkins, Patrick Kabanda, Meghan Miner, Gabriela Romanow, and Sammy Sousa. Our interns are Mary Bates and Sophie Golden. Jeff Turton is our technical director. Alison Lirish Dean composed our themes. You can find us anytime at LOE dot org – and while you're online, check out our sister program, Planet Harmony.
Planet Harmony welcomes all and pays special attention to stories affecting communities of color. Log on and join the discussion at my planet harmony dot com. Also don't forget our Facebook page, it's PRI's Living on Earth, and you can follow us on Twitter at livingonearth, that's just one word. Steve Curwood is our executive producer. I'm Bruce Gellerman. Thanks for listening!

ANNOUNCER ONE: Funding for Living on Earth comes from the National Science Foundation supporting coverage of emerging science; and Stonyfield Farm, organic yogurt and smoothies. Stonyfield invites you to just eat organic for a day. Details at justeatorganic dot com. Support also comes from you, our listeners, the Go Forward Fund, and Pax World Mutual and Exchange Traded Funds, integrating environmental, social and governance factors into investment analysis and decision-making. On the web at paxworld dot com. Pax World for Tomorrow.

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