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Troubled Waters - Canadá
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Video ganador del concurso Jóvenes Reporteros 2006-2007 en Canadá.
There's something dying in our backyard, it's not pretty, scientists are alarmed, we aren't
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sure what's causing this, not entirely. There's a lot of finger-pointing and a lot of blame.
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If you're one of the 6.6 million people who live in BC, Alberta, Saskatchewan, Manitoba,
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Ontario, or Montana, North Dakota, South Dakota, or Minnesota, then you're adding to the problem.
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Do you flush your toilets? Do you use the dishwasher? Does your family fertilize your
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lawn? Then you're having a negative impact on our backyard. The thing that might be dying is Lake
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Winnipeg. Here's proof that our lake may be dying. These are satellite and aerial images of Lake
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Winnipeg. What you see are the potentially toxic blue-green algae blooms. But what is feeding these
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algae blooms? A bit of history. In 1970, Manitoba Hydro started controlling water levels on Lake
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Winnipeg. And interestingly, algae levels quadrupled between 1970 and 2000. In 1992,
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massive algae blooms were spotted by fishers in the North Basin. And in 2003, a full survey of
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the lake was done, the first since 1969, which showed that half of the northern basin of the
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lake was covered by these possibly toxic algae blooms. We invited a research scientist to our
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class to explain to us how Lake Winnipeg got sick. Dr. Karen Scott, a microbiologist, has been involved
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with Lake Winnipeg for many years, both as a sailor and as the outreach coordinator for the
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Lake Winnipeg Research Consortium. After meeting with Karen, we wanted to see the lake for ourselves.
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We spent the day on the research consortium's vessel, the Nemeo. There we met with scientists
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and got to watch them taking lake samples at different research stations in the South Basin.
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As an added bonus, an Environment Canada weather buoy was set out. This was interesting because
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they use a GPS system to exactly position it on the lake. They also use GPS to get to their
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different research stations. Once at a station, they cast out a large trawling net to collect
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fish samples from the surface. They also take water samples and cast out a small mesh net
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to collect zooplankton samples. When the boat comes to a stop, they collect sediment samples
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from the lake bottom. Once the samples are collected from each of the different research
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stations, they are bagged or bottled and taken down to the hold where there is a little lab.
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Some samples are sent to the freezer for later study and some have to be looked at right away.
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After the lake bottom was sampled, we had a chance to hold the animals from the sediment,
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as well as help the scientists sort the fish according to species. We then sat down with Dr.
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Alex Salke, a well-respected biologist, who helped us understand how the fish and lake interact.
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The lake is a house of animals, as we said before, with a family of animals. Anytime you affect one
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of those inhabitants, you affect the whole house. So any change in the system, any additional animal,
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or any change in the temperature, any change in the quality of water, that will affect the lake.
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That will affect the house those animals live in. And that's what man is doing regularly. We're
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changing things like that. We're adding new species. We're changing the habitat that these
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animals live in. And every time we do that, we affect who can live there. And so the house shape
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won't change, but the contents of the house can change. And that's our neighborhood in there. So
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we want to be sure we can keep the same neighborhood. Dr. Bill Franzine helped us to
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better understand the aquatic food chain and what a typical lake looks like. Lakes contain fish,
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zooplankton, which are small animals, different types of algae, and benthos, sediment creatures
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like clams and insects. Lakes also have nutrients, which all plants and animals need, like nitrogen
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and phosphorus. Now, typically, fish eat smaller fish or benthos and zooplankton, while zooplankton
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eat algae. Algae need three things to survive. Sunlight, carbon dioxide, and nutrients. Lake
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Winnipeg's problem is that it has too many nutrients, especially phosphorus, which is seeping
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into the lake from all over the watershed. And this is why the nasty blue-green algae that can
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be toxic are thriving. They are eating the phosphorus and are able to pull out any additional
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nitrogen that they may need from the atmosphere. This is something that other types of algae can't
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do. As a result, the blue-green algae are eating like kings and are creating big blooms and serious
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problems. Every time you throw something on your yard or put a pesticide on your garden,
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that's going to Lake Winnipeg. What you're living with right now is the mismanagement
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of the last 50 years of chemicals and pesticides. You notice some differences about Lake Winnipeg?
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I've noticed huge differences in Lake Winnipeg. When I was a kid, there used to be all these
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little clam shells all over the place. There isn't anymore. But in the most recent years,
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I've noticed all this algae in the water. It's all over the place. Has that affected
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any of your fishing? It's had a huge effect on the fishing. First of all, some of this algae is
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toxic and it'll actually kill the fish. It'll actually kill you if you eat enough of it,
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though I know you're smart enough not to. But it also has a huge impact on, first of all,
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it'll kill the fish and it chases them around all over the place. It also has an effect on our nets.
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We get the algae in our nets and it turns them into blankets and it's very, very difficult to
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fish with that. And of course, the fish can see in his blanket. The net is now a blanket. The
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fish can see it and we don't catch any fish. So then that affects my pocketbook. I don't have as
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much money, which I really don't like. How do you think we can stop the algae blooms?
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I think we have to decrease the amount of phosphorus in the lake. That's the main thing.
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How do we go about doing that? There's all kinds of techniques you could use. I mean,
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people can point their fingers at various things. You can point the fingers at the farmers and
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they're putting stuff in their fields and that washes into the water. You can point your finger
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at the humans. We've had a huge impact. Human effluent, human waste from the city of Winnipeg
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has had many spills. Gimli itself has had a sewage spill, the raw sewage into the lake.
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That's an absolute no-no. We can't allow that to happen.
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We asked Bruce what questions he would put to the politicians we plan to interview.
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Questions I would put is, what's been done? What are you going to do and when? Give us some
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timelines. You've done all this research. All of this has been done. It's actually been done
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two or three times. When are you going to actually do something? When are we going to
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see some concrete results? Because this is something that I fundamentally believe,
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that if all the science in the world, all the research and all the talking in the world,
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we could know exactly what's going on in Winnipeg. If you don't do anything, at the end of the day,
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we're going to have a really good record of how a lake dies right to its death. We don't want that.
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Sometime before that, we want to see some action. If we don't have that action,
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we will have a nice record of a lake until it dies. I think that you can say, you've been told
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by a fisherman that all the talk and all the work they've done, all the talk and all the work they
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haven't done, is less than one guy walking along a riverbank, seeing a cow patty and kicking it
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back three feet. If you don't do anything, then that's more than all the science and all the
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research in the world. If you don't do anything, one man kicking a cow patty three feet.
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How do you think we can change the health of Lake Winnipeg?
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Well, we can try to use less phosphorus in our water supplies and try to keep our sewage from
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going in the lake and all those good things. But, you know, we have a very large agricultural
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drainage basin and I don't think we're going to stop farming. So all we can do is the best
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management practices that we can do and try to reverse or at least stall the trend that's been
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going on. With our watershed being as large as it is, 950,000 square kilometers, there's a lot of
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blame to share. We can look at the use of fertilizers on farmland and in the city, at the
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hog industry, at hydroelectric dams, at water treatment plants, at sewage bills, and at our use
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of chemicals, pesticides, and especially phosphorus. So what can we be doing to help address Lake
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Winnipeg's poor health? Well, we can restore the shoreline to a more natural state, make sure that
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septic systems are in good shape, not flush things down the toilets that don't belong, use products
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that have a low phosphorus content, keep large animals away from shorelines of streams, rivers,
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and lakes, and not put anything into the watershed that is toxic or may cause shore erosion. We plan
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to take it one step further. We're going to send our documentary to all levels of government,
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meet with local politicians, and demand action. We want to clean up our backyard.
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- Valoración:
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- Idioma/s:
- Autor/es:
- Alumnos del Cecil Rhodes School
- Subido por:
- EducaMadrid
- Licencia:
- Reconocimiento - No comercial - Sin obra derivada
- Visualizaciones:
- 733
- Fecha:
- 10 de diciembre de 2007 - 13:25
- Visibilidad:
- Público
- Enlace Relacionado:
- Alumnos del Cecil Rhodes School (Manitoba, Winnipeg) de Canadá
- Descripción ampliada:
- Causes and effects of the "dying" Lake Winnipeg. The video was sent to local government officials to alert them to the issue.
- Duración:
- 09′ 59″
- Relación de aspecto:
- 4:3 Hasta 2009 fue el estándar utilizado en la televisión PAL; muchas pantallas de ordenador y televisores usan este estándar, erróneamente llamado cuadrado, cuando en la realidad es rectangular o wide.
- Resolución:
- 488x366 píxeles
- Tamaño:
- 49.38 MBytes