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Green Guru
Advice for the eco-minded.


What air-filtering plants do you recommend?
—Matt James, New York, NY

There are few better ways to freshen and filter the air in your home or office than investing in some green. Plants reduce a room’s dust levels and remove particulates and chemicals from the air. They also turn your exhaled carbon dioxide into oxygen through photosynthesis. “Where you have plants in a building there is a reduction in asthma and an increase in worker productivity,” says Bill Wolverton, a researcher and author of How to Grow Fresh Air.

Kamal Meattle, a business owner and environmental activist, found that out firsthand when he became allergic to the air in his native New Delhi, India. With the help of the Indian Institute of Technology, Delhi, Meattle researched which plants would best improve the indoor environment. He found three that performed exceptionally well. Mother-in-law’s tongue, also called the snake plant because of the shape of its leaves, is ideal in the bedroom, since, unlike most other plants, it photosynthesizes at night. A vine known as the money plant is what Meattle calls “the specialist,” for its ability to filter pollutants such as formaldehyde. Areca palm is a generalist that is effective in most environments, he says.

To see how well your greenery is working, test the air quality with the help of a professional or use an air-quality test kit. (You can buy one online at Green Nest.) After a while you will be able to smell the difference, says Meattle. With some plants in your place, you can breathe easier.
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Why do swamps sometimes smell like rotten eggs?
—Jennifer Watson, Okeechobee, FL

The odor that wafts out of a muddy, decaying wetland may be worse than Swamp Thing’s breath. But that smell means the ecosystem is thriving. “On the whole, wetlands do a lot more good than harm,” says Karen McKee, a research ecologist at the USGS National Wetlands Research Center in Louisiana, a state that’s home to 30 percent of the coastal wetlands in the nation’s Lower 48. “The odor tells us that it’s a healthy, functioning system,” says McKee, “regardless of what it smells like.”

From swamps and bogs to fens and marshes, all wetlands are oxygen-deprived environments where microscopic anaerobic bacteria break down organic matter and—in the process—produce hydrogen sulfide: the source of the stink. Despite the bad smell, decay benefits the system because it also reintroduces carbon, oxygen, and sulfur, vital elements that get cycled back into the ecosystem for organisms to use.

Healthy wetlands are crucial because they supply wildlife—including much of the fish and shellfish we eat—with habitat and nursery grounds and they act as buffers from hurricanes and storms. Some wetlands also store and produce methane, a greenhouse gas 20 times more potent than carbon dioxide. Scientists are looking at whether wetlands function as valuable greenhouse-gas “sinks,” or storage areas, that can help slow climate change, but more research is needed.

Next time you catch a whiff of hydrogen sulfide at the swamp, remember: It may smell bad, but it’s all good.
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Which beverage is greener: beer or wine?
—Sarah Miller, Denver, CO

Figuring out the environmental impact of beer compared with wine, from grape—or hop—to glass, isn’t easy, but many experts agree that growing organically is better for the environment. Organic practices are pesticide-free and can provide habitat for wildlife. In addition to “organic certified,” look for such labels as “biodynamic,” “sustainable,” and “grown with organic grapes.”

Both wine and beer are often bottled in glass, which is heavy and usually makes its way to the landfill instead of the recycling plant. Many vintners are now reducing the weight of their bottles, decreasing costs and emissions during transport. If you’re comparing carbon footprints, boxed wine is a far better option, says’s Tyler Colman, a wine professor and coauthor of a study on the topic. Boxes are recyclable and lighter, resulting in fewer greenhouse-gas emissions during shipping. For the same reason, aluminum cans are preferable to glass beer bottles, if they’re recycled.

Trucks transporting wine bottles emit more greenhouse gases than boats do. Therefore, if you’re on the East Coast, buying wine from Bordeaux, France, has less environmental impact than picking up a bottle from Napa Valley, California. Cut your carbon calories further by drinking local. All 50 states now produce wine, and microbreweries are growing in numbers.

Refrigeration also plays a role. Beer is often put in the fridge at the store (more so than wine). A life cycle carbon footprint analysis of Fat Tire beer found that refrigeration accounts for the largest percentage, more than a quarter, of its greenhouse-gas emissions. Whether you choose beer or wine, just remember these two guidelines: Look for certifications on the label, and drink local (maybe starting on your own front porch).
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