Archive for the ‘Meio Ambiente’ Category

Água Lastro e consequências econômicas

setembro 1, 2010

O mais recente lançamento do Professor Tiago Vinicius Zanela, pela editora Juruá, aborda, entre outros assuntos, as consequências econômicas da efeito da água de lastro. Para adquirir clique aqui.


Embarcações e navios podem atuar como vetores de dispersão de espécies marinhas exóticas através da água que utilizam como lastro. Todo navio, quando não esta carregado ou trafega apenas com uma parte da sua capacidade de transporte de cargas, necessita de algum peso que sirva como lastro para dar equilíbrio, sustentabilidade e manter sua integridade física. Atualmente utiliza-se a água do mar como lastro para que a segurança dos navios e tripulações seja mantida mesmo navegando sem carga ou parcialmente carregado. A grande questão é que essa água transporta organismos e espécies de uma região à outra, causando sérias perdas ambientais, econômicas e sociais aos países bioinvadidos. Esta obra tem por finalidade verificar as consequências socioambientais, econômicas e jurídicas da bioinvasão via água de lastro fazendo uma construção histórica dos problemas socioambientais, focalizando a questão marinha e a água de lastro. Para isto, este livro analisa como a água de lastro se tornou um problema, quais os principais exemplos deste tipo de bioinvasão e como o mundo e, em especial, o Brasil reagem diante do tema.


Conheça os trabalhos de Elinor Ostrom, vencedora do Nobel de Economia

maio 2, 2010

Confira no Milênio, canal GLOBONEWS, desta segunda-feira (3), às 23h30.

A cientista política Elinor Ostrom é a primeira mulher a receber o Nobel de Economia. Ela dividiu o prêmio, no ano passado, com o economista Oliver Williamson.

De infância pobre, Elinor se especializou em buscar exemplos e analisar pequenas sociedades que, em vez de competirem entre si pelos mesmos recursos naturais até a extinção, aprenderam a cooperar para sobreviver.

Seus trabalhos comprovam que, em muitos casos, sociedades são capazes de prosperar, criando alternativas para resolver conflitos de interesse, respeitando o semelhante e garantindo sustentabilidade ambiental. É isso que a Nobel de Economia, Elinor Ostrom, explica a Lúcia Araújo, diretora do Canal Futura, nesta entrevista exclusiva para o Milênio feita em Bloomington, na Universidade de Indiana. Confira no Milênio desta segunda-feira (3), às 23h30.

Paper or Plastic? Uh…Can I Get Back to You?

abril 30, 2010

“Paper or plastic?” It’s probably the single most common question in daily life – a query that can lead to embarrassing indecision, a kind of eco-paralysis that spares neither the planet nor the people standing behind you in line.

As it turns out, the environmentally correct answer to the question isn’t as straightforward as you might think.  In California, even the state’s highest court is debating the issue, as it prepares to decide whether communities can ban plastic bags at grocery stores without first studying the environmental effects of the increased use of paper.

The conventional wisdom is that a bag made of paper is the more earth-friendly option. Indeed, on that assumption, San Francisco banned plastic bags in grocery stores in 2007. Other California communities, including Oakland and San Jose, are also considering their own plastic bag prohibitions. Meanwhile, since January, grocery shoppers in Washington D.C. have been charged a five-cent tax on all disposable bags – both plastic and paper. And Baltimore’s City Council is considering a ban on plastic bags or a levy on all disposable bags. Even environmental laggard China banned the use of ultra-thin plastic bags in 2008, while consumers in Italy, Belgium, Switzerland, Germany, and Ireland all now pay a surcharge for using plastic.

Eco-conscious grocers such as Whole Foods Market have cast their votes as well, eliminating plastic bags and offering only paper sacks. At grocery stores that offer both, it’s not unusual to hear those opting for plastic adding a shamefaced, “Sorry!”

THE ENVIRONMENTAL IMPACT of the 50 to 80 billion plastic shopping bags Americans use every year is indeed significant. For one thing, a plastic shopping bag can take as long as 1,000 years to decompose in a landfill. If Norse explorer Leif Eriksson had left a plastic bag behind when he became the first European to visit North America, the bag would just now have decomposed.

And because plastic bags easily become airborne, they turn up as litter in much greater numbers than do paper bags. (In China, the blizzard of plastic bags swirling through the streets is known as “white pollution.”) The British Antarctic Survey has found plastic bags floating north of the Arctic Circle, and as far south as the Falkland Islands. Plastic bags pollute lakes and rivers and contribute to what’s been dubbed The Great Pacific Garbage Patch, a gyre of trash in the North Pacific Ocean. Floating plastic bags aren’t just unsightly; they also kill. An unknown number of turtles and other sea animals die each year after ingesting discarded plastic bags, which they mistake for food.

SO THAT MUST MEAN paper bags are always better for the environment than plastic ones – right?

Not so fast, Green Avenger.

Overall, the evidence does not support the widely held view that paper bags are far more environmentally friendly than plastic. Paper bags, after all, require considerably more energy and resources to produce than plastic ones. The manufacture of an uncomposted paper bag generates nearly 40 percent more greenhouse gas emissions than a plastic bag does. What’s more, plastic grocery bags consume 71% less energy during production and require less than 6% of the water needed to make paper bags. And since paper bags weigh six to ten times more than plastic, they require more fuel to transport them to stores and take up more space in landfills.

Then there’s deforestation: about 14 million trees are cut down every year to satisfy America’s consumption of paper shopping bags. That means that the manufacture of paper bags delivers a climate change double-whammy. Not only are large quantities of greenhouse gases produced, but the number of CO2-absorbing trees is also cut back.

And while it’s true that plastic bags may take as long as a millennium to decompose, paper bags often don’t fare much better. Due to the lack of water, light, and oxygen in many modern landfills, paper doesn’t break down significantly faster than plastic does.

The difference in environmental impact between the two materials is so narrow that some environmentalists answer the “Paper or plastic?” question with another question: “Where do you live?” People who live by the water, they say, should choose paper, since plastic threatens marine wildlife, while residents in the interior should opt for plastic, since it results in fewer greenhouse gases and can be reused more often than a paper bag.

OF COURSE, THE MOST ENVIRONMENTALLY CORRECT response to the “Paper or plastic?” question is: “Neither, thank you, I have a reusable shopping bag.”  But even reusable bags are not always what they seem. Whole Foods Market currently sells a reusable shopping sack called A Better Bag that’s made from 80 percent post-consumer recycled plastic bottles. There’s even a special edition of the bag endorsed by musician and environmental activist Sheryl Crow, for shoppers who want to save the Earth until the sun comes up over Santa Monica Boulevard.

But A Better Bag, it turns out, could be a lot better. Whole Food’s reusable bags are manufactured in Shenzhen, China, and shipped thousand of miles by ship and truck to stores in the United States. A truly better bag would be, say, a Fair Trade reusable tote bag made by a producer-owned cooperative in Central America. But you’d still have to factor in the environmental impact of transporting the bags all the way to the U.S. That might have you considering the merits of a locally-produced reusable bag made of organic hemp, or perhaps one fashioned from post-consumer recycled material, or … but by then, of course, everyone in the grocery store line will be yelling at you.

THE FACT IS, even if you lug your groceries out of the store in a certifiably earth-friendly reusable bag, you shouldn’t be so quick to congratulate yourself.

“The grocery bag is not the real problem,” says Bob Lilienfeld, editor of the Use Less Stuff report, “it’s all the stuff you put in the bag. The amount of environmental damage done by the bag is about one-tenth the damage done by the products inside.”

Lilienfeld and others say that if you really want to do something good for the planet, reduce, reuse, and recycle – in that order. Reducing consumption isn’t a message that often gets heard in a country whose economic wellbeing depends on people buying more stuff. But ultimately, doing more with less may turn out to be the most sustainable answer to the incessant “Paper or plastic?” question.


Governo intervém no mercado de recicláveis

março 22, 2010

O presidente Luiz Inácio Lula da Silva deverá editar um decreto estabelecendo uma política de preços mínimos para os produtos reciclados.

Leia a matéria completa clicando aqui.

Fonte: Agência Brasil.