Curbing Nitrogen Pollution

Across the country, forests, streams and coastlines are getting extra doses of nutrients containing the element nitrogen. Researchers say the long-term impact of these unwanted compounds on the environment could be serious. The Great Lakes Radio Consortium’s Daniel Grossman reports on some efforts to reduce nitrogen pollution:

Transcript

Across the country, forests, streams and coastlines are getting extra doses of nutrients
containing the element nitrogen. Researchers say the long-term impact of these unwanted compounds on the environment could be serious. The Great Lakes Radio Consortium’s Daniel Grossman reports on some efforts to reduce nitrogen pollution:


A thunderstorm soaks the land and lights the sky. The electric jolts of the lightning change nitrogen in the air into compounds needed for plants to grow. Lightning, as well as microbes in the soil, converts annually nearly 100 million tons of atmospheric nitrogen into plant nutrients. Humans make the same compounds in factories and call them fertilizer, a mainstay of agriculture. Between these synthetic chemicals and a smaller quantity of related compounds produced when fossil fuels are burned, humans produce more nitrogen-rich nutrients than nature makes on the seven continents. University of Minnesota ecologist David Tilman says such extra nutrients are a concern.


“Right now half or more of the nitrogen we put on a farm field just washes through the soil and down into the groundwater into lakes, rivers, streams and into the ocean.”


This wasted nitrogen often travels great distances causing widespread damage. Tilman says on land, the nutrients cause exotic weeds to outgrow native plants. In the ocean, the nutrients cripple critical habitats. The ecologist says nitrogen pollution must be cut. One place to start is on the farm.


“We have to find some way to grow crops where the crops take up much more of the nutrients that we apply.”


(Sound of walking through grass. Quiet bird calls in background.)


Near Chesapeake Bay, farmer and agricultural scientist Russ Brinsfield walks across a patch of tall dry grass.


We’re on the edge of a field, about a sixty-acre field of corn, on the beautiful Eastern Shore of Maryland.


This field is a research plot at the Maryland Center for Agro-Ecology. Here Brinsfield is studying agriculture’s environmental impact. Chesapeake Bay’s waters have high concentrations of farmer’s nutrients, causing blooms of the toxic algae Pfiesteria. The pollution has also caused declines in sea grass beds. Brinsfield says solutions to the problem fall into two categories.


“The first series of practices are those practices that we’ve been able to demonstrate that by a farmer implementing them he can reduce his inputs without affecting his outputs… that at the end of the year have added profit to his bottom line.”


For instance, testing the soil’s nitrogen level before fertilizing. And splitting fertilizer applications into two doses rather than one so that nutrients are added only when plants need them. Such simple measures are good for environment and the bottom line. Brinsfield says in the last 10 years most farmers on the Eastern Shore of Maryland have cut fertilizer use this way. Then there’s the other category of improvements.


“We’re going to have to do some things-ask some farmers to do some things-that may cost them more to do than what they are going to get in return from that investment.”


For example, in the winter, many fields here are fallow and bare. That means top soil erodes when it rains, taking with it residual fertilizer. It wasn’t always this way.


“I can remember my dad saying to me, ‘every field has to be green going into the winter, Son.’ So all of our fields were planted with rye or wheat or barley. It served two purposes. First, the animals grazed it. And second, it held the soil intact.”


And intact soil retains its fertilizer. Such winter cover crops also prevent fertilizer loss by storing nutrients in plant leaves and stalks. This used to be dairy country and cover crops grazed by cows made economic sense. Now farmers mostly grow grains. Planting a cover crop could cut nitrogen flow from farms by 40 percent but it costs farmers about $20/acre and provides no economic benefit to them. Brinsfield says farmers need an incentive.


“For the most part, farmers are willing to participate and to do those things that need to be done, as long as they can still squeak out a living.”


To help them squeak out a living, the state pays some farmers to sow cover crops. The state also pays them to plant buffers of grass and trees that suck up nutrients before they leave the farm. Today farms in six states that are part of the Chesapeake’s huge watershed contribute about 54 million pounds of nitrogen to the bay. The goal is to cut this figure approximately in half by two thousand and ten. Robert Howarth, a marine biologist and expert on nitrogen pollution at Cornell University, says though ambitious, this target can be achieved.


“I think most of the problems from nitrogen pollution have relatively straightforward technical fixes. So the real trick is to get the political will to institute these.”


Howarth says much of the nitrogen problem could be eliminated with a blend of government subsidies and regulations. But more will be needed as well… solutions of a more personal nature.


(sound of Redbones Barbeque)


There’s a pungent, smoky aroma in the air at Redbones Barbeque in Somerville, Massachusetts. The crowded bistro serves up a variety of ribs, chicken, sausage and other meats, dripping with savory sauces. University of Minnesota ecologist David Tilman says when someone eats a meal they are responsible for the little share of fertilizer a farmer somewhere had to apply to grow a crop. If the meal is from farm-raised animals, like the heaping plates of meat served here, the amount of fertilizer is much greater than if it’s from plants.


“It takes from three to ten kilograms of grain to produce a single kilogram of meat.”


Tilman says if Americans ate less meat, they could dramatically reduce fertilizer usage. However, per capita consumption is rising. Meat consumption is on the rise globally as well. David Tilman would like that to change. He says if current trends continue, human production of nitrogen nutrients will grow to triple or quadruple what nature makes on all Earth’s lands. Professor Tilman says that in many places the impact on the environment would be catastrophic.


For the Great Lakes Radio Consortium, this is Daniel Grossman.

Cooling the City With Green Rooftops

  • The City Hall in Chicago is topped with plants and trees to try to cool things down. The city is working to reduce the heat island effect caused by so many blacktop roofs and parking lots. Photo by Lester Graham

On the nightly TV news in large cities, the meteorologist sometimes talks about the heat island effect. That’s where all the blacktop roofs and asphalt parking lots soak up the heat and increase the temperature on a hot summer day. One major U.S. city is trying to do something to reduce that effect. To set an example, the mayor decided to start with City Hall. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

On the nightly TV news in large cities, the meteorologist sometimes
talks about the heat island effect. That’s where all the blacktop roofs
and asphalt parking lots soak up the heat and increase the temperature
on a hot summer day. One major U.S. city is trying to do something to
reduce that effect. To set an example, the mayor decided to start with
City Hall. The Great Lakes Radio Consortium’s Lester Graham reports:


Standing on the roof, eleven stories up, isn’t really far enough to escape
the noise of the city below. But this rooftop is an escape. It’s a garden, a
big one. There are even trees. Not in pots, but actually planted on… or…
in the roof.


Marcia Jiminez is the Commissioner of the City of Chicago’s Department of Environment. She says Chicago wants building owners to
do what they can to cool the city down… and planting gardens on the
roof is one way to do it. So that’s what the city did on top of City Hall.


“Well, the garden on the rooftop is addressing what we call an urban heat
island problem. By putting the garden with light colored pavers and the
green plants on top of the roof, we’re actually helping to use less energy
inside the building and it actually helps to keep the building cooler.”


Cooling down the building is just the beginning of this garden. Despite
being eleven stories up in the middle of downtown, the roof is alive with
bugs and butterflies.


“Actually birds and all of the insects, many of them, have found their
way up here. We’ve actually put up birdhouses to study what kind of
birds are coming to the rooftop garden. This is a place of
respite as well as a place to feed.”


The whole rooftop has become something of a lab. Scientists research
what animals have made a home here… and they’re monitoring how the
plants are spreading.


Kimberly Worthington worked on the City Hall project to see it go from
the drawing board to rooftop. She says they chose plants for color, form
and for survivability.


“The design that we went with was low maintenance, was what we were
looking for in our plant selection. And the landscape architects that were part of the design team focused on plants that would require less water. And they also wanted to keep as many native plants as possible. So, there are a lot of prairie plants up here.”


The Chicago City Hall rooftop project also reduces rain water runoff. 75-percent of a one-inch rain will be soaked up right here in the garden. That’s good because too much rain overflows sewers into Lake Michigan. If enough buildings in the city had rooftop gardens, stormwater runoff problems would be curtailed a bit.


While the city is touting the environmental benefits of its rooftop garden, in another part of the city a planned rooftop garden is all about people.


Brenda Koverman is with the Schwab Rehabilitation Hospital in Chicago. We’re up on the roof where she’s showing me landscape renderings of how the surrounding area will look once the planting begins. Stone paths, fountains, flower gardens and shrubs.
It’ll look beautiful. And it’ll probably cool things down up here. But Koverman
says this is for the patients who are learning to be mobile after disabling injuries. The hospital hopes that patients in rehabilitation will find the rooftop garden more pleasant and helpful than institutional tile floors and plastic obstacles as they learn to
manuever…


“You know, so, are patients more able to maneuver their wheelchairs in the community? Are patients able to use their hands better so they can cook better at home? Are patients able to stay out of the nursing home and go to their home? So, if we can get any kind of
those outcomes, then it’s a huge success.”


It might be more interested in the patients, but the hospital will still be helping Chicago reduce its heat island effect.


There aren’t very many of these projects in the city, so it’s hard to say whether the rooftop gardens could cool things down all that much. But Environment Commissioner Marcia Jiminez says all you have to do is go up on the roof on a hot day. City Hall sits right next to the County Building. In fact they look like the same building. But not from the roof. Only one side is garden.


“In last summer in 2001 on the hottest day, while it was about a hundred degrees on the city hall side, it was 165 on the opposite end of the building where’s there’s a blacktop roof.”


Even if you’re not interested in planting a garden on your roof, the city still requires some effort to cool things down. City ordinance calls for light colored material when a roof is replaced. And parking lots have to plant some trees before they can get a permit to resurface. Rooftop gardens aren’t mandated… but city officials say they’re learning first
hand that it’s a much better use of space in the city.


For the Great Lakes Radio Consortium, this is Lester Graham.

ZOOS SET STAGE FOR WILDNESS (Part 1)

  • Today's zoo exhibits attempt to immerse visitors in the scene while also enriching the animals' lives. Some zoos are criticized for emphasizing appearances instead of the animals' well-being.

Zoos across the nation are putting their animals in more natural settings instead of cages. For some zoos, it’s done to make the animals’ lives a little more comfortable. But for others, it’s simply done to draw more people rather than to give the animals a better place to live. The Great Lakes Radio Consortium’s Lester Graham has the details in the first of a two-part series:

CONSTRUCTING NATURAL HABITATS (Part 2)

  • This grizzly at the St Louis Zoo is displayed in an exhibit that mimics its natural habitat. A whole industry has emerged to manufacture these exhibits.

At your local zoo – if you can suspend disbelief for a moment – you might find yourself in the middle of a tropical rainforest. Or a dusty African plain, watching the animals in their natural habitat. Of course, those wild settings are merely a façade. Clever construction techniques covering up concrete cages. In the second of a two-part series, the Great Lakes Radio Consortium’s Lester Graham reports… the thought and planning behind the displays can be nearly as intricate as nature itself:

Computing Better Fuel Efficiency

Automotive researchers say a newly developed computer-controlled fuel system could help make SUVs more fuel efficient. The Great Lakes Radio Consortium’s Tom Borgerding has more:

New Method Assails Exotic Hitchhikers

A new way to prevent rust in the ballast of ships might also prevent many alien aquatic animals from being transported from port to port. The Great Lakes Radio Consortium’s Lester Graham has details:

CANADIAN ‘SPECIES-AT-RISK’ ACT TOO WEAK?

More than 1,300 U.S. and Canadian scientists are asking the Canadian government to strengthen proposed legislation that would protect endangered species. The Great Lakes Radio Consortium’s Karen Kelly explains:

Transcript

More than 13 hundred U.S. and Canadian scientists are asking the Canadian government to strengthen proposed legislation that would protect endangered species. The Great Lakes Radio Consortium’s Karen Kelly reports.


Right now, endangered species in Canada have no federal protection. The new Species at Risk Act would make it illegal for people to kill the 3 hundred 80 plants and animals considered at risk. But unlike the American law, the proposal does not guarantee that the land or waters in which these animals live will be protected from development. University of Ottawa biology professor David Currie says that’s led to a protest among scientists.


“Virtually all of the studies that have been done on the reasons why species become endangered or go extinct have shown that at least some aspect of habitat loss is involved and in many of the most dramatic cases of extinction, species’ habitats have been simply been entirely wiped out.”


The government’s environment committee will consider amendments to the bill in October. For the Great Lakes Radio Consortium, I’m Karen Kelly.

Mallard Ducks on the Decline

  • In a narrow swath of grass in a roadside ditch, a mallard hen nests her second brood of the season, a rare event for these ducks. Her first ducklings were killed by a predator.

In the last decade or so, ducks in the Great Lakes region have not been reproducing as well as they have in the past. The number of ducklings hatching out and surviving to adults has dropped by about 25 percent. Researchers are trying to figure out why this is happening and what can be done about it. The Great Lakes Radio Consortium’s Lester Graham went into the field with researchers and has this report:

Transcript

In the last decade of so, ducks in the Great Lakes region have not been reproducing as well as they have in the past. The number of ducklings hatching out and surviving to adults has dropped by about twenty-five percent. Researchers are trying to figure out why this is happening, and what can be done about it. The Great Lakes Radio Consortium’s Lester Graham went into the field with researchers and has this report.


(sound of quack, quack overhead / cross fade to truck doors and engine startup/ bed of gravel sounds)


Mallard ducks are the most common duck found throughout the Great Lakes states. You’ll see them on farm ponds, college lagoons, and even in big city parks. But recently the mallard’s population hasn’t been growing as fast. The duck’s rate of reproduction has been falling off in the region since the mid-1980’s. Researchers with the sportsman’s conservation group, Ducks Unlimited, are involved in a three year study of mallards to find out why the ducks are not surviving in as great of numbers.


Tina Yerkes heads up the project. In a truck with something that looks like a TV antenna on top, fellow researcher John Simpson and she are in northwest Ohio, near Lake Erie, headed out to find some of the mallard hens. Tiny transmitters were surgically implanted in the ducks earlier this year and the antenna tracks the signals.


“So, this is the whole gizmo setup here. Everyday these guys go out and they track the birds. Each bird has a unique beep, if you will, uhm, a frequency. And that’s basically how we figure out what they’re doing. We started with 57 and you’re down to 38?
JS: Thirty-eight, roughly. And, eleven? JS: Twelve. Twelve have actually been killed, either by predators or farming operations on this site.”


(Truck sound under)


As the truck gets close to the last sighting of one of the mallard hens they’re tracking. John Simpson flips on the tracker and turns the antenna.


(beep beep sound)


He’s pulled over along a fairly busy road, and starts looking around in the roadside grass.


“So, she’s actually nesting in the ditch?”
“Yeah. I’m not entirely sure where her nest is here, so we’ve got to be careful.”


(sound of grass rustling)


It’s hard to believe a duck could find a place for a nest here. Most of the roadside is mowed except for a little strip of grass where we’re looking. She’s one lucky duck. A mower would kill her and destroy her nest.


“There she is right there. See her sitting on her nest?”


The mallard hen is three feet away and she’s still hard to see. John
Simpson has to flush her so that he can take a look at the eggs in the nest.


(Sound of flapping wings)


“There she goes.”
“She’s got a pile of eggs too. That’s her second nest.”
“That’s her second nest?”
“Yeah. She had a pile in her first nest.”
“Twelve eggs? Is that right?”
“Eleven.”
“Eleven?”
“Yep.”


(Ambience remains under)


The duck lost her first brood to a predator. Since she had nested close to a subdivision, it could have been a dog or cat. But the researchers say in this case it was probably a wild predator, maybe a raccoon.


“And, once we’re finished, we’ll just cover the nest so the predators don’t see it and we leave.”


It’s very rare that a mallard hen tries twice to raise a brood, But in this area the ducks are adopting a lot of unusual behaviors. Since there’s almost no grassland to nest in, hens have nested in hay fields where they’re usually killed at mowing time. One hen made a nest in a large flowerpot. At our next stop we found a duck in the backyard of a mobile home, and her eggs had just hatched.


(Peep, peep, peep of the ducklings)


The owner mowed around the duck’s nest, giving the mother and her eggs a chance to survive. Now that they’ve hatched, they’ll head to the water nearby. Tina Yerkes says development pressures have hurt the ducks here.


“In Ohio, we’re looking at pretty bad brood survival which tells us that probably we need to alter the landscape by putting wetlands back—by restoring wetlands and managed marshes for the broods. And then, probably also coupling that with some grassland habitat, ’cause as you can see, there’s not a lot of grassland habitat for them to nest in here. We need to improve that.”


The Ducks Unlimited researchers are getting some indications about what kinds of things are hurting the ducks ability to reproduce. Besides the loss of wetlands the researchers are finding that farming practices such as frequently mowing ditches and urban sprawl taking up grasslands are all contributing to a high mortality rate among ducklings and sitting hens. But the researchers haven’t collected enough information yet to make any solid conclusions. It’ll be two more years and many more sites before the Ducks Unlimited researchers have enough hard data.


Robert Payne is the Curator of Birds at the University of Michigan Museum of Zoology. He says while to researchers it might seem pretty clear that people are causing the lower rates of production in the duck population. Information like the Ducks Unlimited group is gathering will be helpful.


“Well, it seems to be common sense: the more people, the more development you have, the fewer places there are going to be for birds. But the people in our society who make the decisions like to have some data out there. (They) Like to know how many ducks, how much land, and so on. Otherwise, these people can’t really figure how much land the really should set aside for the ducks. No data, no well informed decisions.”


(sounds of birds and bullfrogs)


But some people might find data that are supposed to help ducks gathered by a group that’s chiefly supported by people who kill ducks for sport might be a bit of a conflict, or at least very self-serving. Ducks Unlimited researcher Tina Yerkes says there’s a larger purpose here than merely making hunters happy.


“The purpose is not necessarily to create more ducks to shoot, but the purpose is to alter and affect the landscape in a positive way for all the species that need the landscape. So, we’re trying to take a step back and determine what the wildlife needs and help put it back on the ground for the wildlife.”


Predictions are that the human population around the Great Lakes will steadily increase for the foreseeable future, and if the researchers’ early indications hold, it’ll likely affect the duck population even more. This study, when it’s complete, might give policy makers the information they need to find a balance between the needs of people and the needs of wildlife as the conflict between the two grows in the Great Lakes region.


For the Great Lakes Radio Consortium, this is Lester Graham.

Related Links

MALLARD DUCKS ON THE DECLINE (Short Version)

Mallards are the most common duck in the Great Lakes region, but their numbers have been declining during the last few years. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

Mallards are the most common duck in the Great Lakes region, but their numbers have been declining during the last few years. The Great Lakes Radio Consortium’s
Lester Graham reports.


The sportsmen’s conservation group, Ducks Unlimited is involved in a three year study, trying to learn why mallard duck populations are not increasing in the same numbers they once were. Tina Yerkes is a research biologist with the organization. She says starting in the mid-1950’s mallard flocks were growing at a pretty rapid rate.


“In the Great Lakes area, after the mid-80’s until now the production ratio has dropped and it’s dropped pretty sharply. And that for us is a warning bell, if you will, that something is going on in this area that’s causing birds not to do well.”


Yerkes and a team of biologists in Michigan, Wisconsin, and Ohio are tracking mallard hens and their broods. Early indications are that loss of habitat is beginning to affect the duck populations in the region. For the Great Lakes Radio Consortium, this is Lester Graham.

Biological Control Gone Awry

Many of the earth-friendly pest control methods developed by organic farmers have become popular among gardeners and homeowners. But when Great Lakes Radio Consortium commentator Tom Springer bought guinea hens to eat troublesome insects, he ended up with a different kind of pest… and a new respect for the challenges of organic agriculture: