Discovery News: Environmental

Green Life at the Fair

So... summer's over. I know because the Minnesota State Fair ended yesterday.

State law says school can't start before the fair is over. People here say things like, "I can't believe the fair starts tomorrow!" (i.e. "I can't believe a few days of livestock showings, Whac-a-Mole games, and fried food on a stick is all that stands between us and six months of -40-degree weather!") One of the public radio hosts even said, on the night before it started, "It's State Fair Eve!!!"

So it's a big deal. And it's a heckuva lot of fun. I went over this weekend, partaking of delicacies like a grilled chocolate sandwich, and all-you-can-drink milk for $1. I went to see the prize-winning pumpkin (834 pounds), and a whole bunch of newborn piglets. I missed checking out the butter booth in the dairy building where the dairy queens of the fair--the finalists for the title of Princess Kay of the Milky Way--each have their busts carved in 90-pound blocks of butter on display.

I also went over to check out the "Progress Center", the headquarters for all things green. Outside the center was a single, full-sized wind turbine blade, planted in the ground like a statue. It was absolutely immense--123 feet long--and elegantly shaped, twisting slightly as it thinned to the tip.

According to the stats printed at its base, the single blade weighed six tons, as much as an African elephant. When in place, at the top of a wind turbine, the tip would rise more than 389 feet into the air, taller than the Statue of Liberty. A turbine made of such blades would produce 1.5 megawatts, which would offset 90,000 tons of CO2 over its 20-year lifetime.

Other highlights from the center included an exhibit showing off how much trash the average Minnesota family of four generates in a year: four tons. The model heap must have been 15-20 feet across and equally tall. It would certainly take up most of my backyard. Thirty-two percent of that is packaging.

One way to reduce all of that trash is by composting... which a Progress Center exhibit described in terms a Minnesotan could really understand: "microbe hotdish".

Hmm... I'll hold out for the more appetizing kind now that winter is just around the corner.

(Image: J. Marshall. For more images of the Minnesota State Fair, check out this NYT slideshow.)

Nemo's Nose

Today Discovery News published an article about research showing how orange clownfish follow the smell of leaves and anemones, presumably to find their way back to the reef anemones they live within.

The researchers recorded how much time each fish spent on either side of a chamber where each side contained water from different sources. This allowed them to measure the fishes' preference for different-smelling water. (Read the details here.)

Above is a video from Jelle Atema of Boston University, who developed the chamber, showing how the experiment works.

He tested a juvenile blue damsel fish with water from its home reef and from a reef 15 miles away. Watch how the fish switches sides when Atema swaps which side carries the familiar water. The fish quickly swims back into its homey water.

The researchers in the study described today observed similar behavior with the clownfish they studied.

I particularly enjoyed reporting on this research because it was such a great example of the scientific method.

The experiments were as simple as a school science fair project in their straightforward comparisons: No particle accelerators or DNA extractions required. But the tests were clever and the results were clean.

What was incredibly striking is just how strong the fishes' preferences were. When presented with beach water, anemone-scented water, or rainforest-leaf-scented water, the fish spent anywhere from 89 to 98 percent of their time in those waters compared with what you might call "unscented" water. When offered water laced with the scent of an unfamiliar tree leaf, all of the fish scooted out of it immediately, spending 100 percent of the time in the neutral water.

This struck me because when I was in college, I took a class in behavioral ecology where we had to try to measure some aspect of guppy behavior for a class project. We were each given a dozen guppies and a wading pool and sent back to our dorm rooms to run an experiment.

Our groups' experiment was to see whether the size of a guppy school affected how fast the guppies found food. We put six little feeding stations (fish flakes floating inside loops made of drinking straws) around the perimeter of the pool and released schools of 1, 2, 4, 6 and 12 fish, and timed how long it took them to find food in the station that was stocked with food (randomly selected by rolling a die).

The problem was, first of all, that we didn't get the experiment done before winter break. So, we decided that I would carry the guppies home on the airplane and do the experiment in my parents' basement. We figured I could just buy a kiddie pool when I got home.

Somehow, it didn't occur to us that NOBODY sold wading pools in December in Colorado.

Then, one of the guppies gave birth and died, so I went to the pet store to replace the guppy with another grownup. Pregnancy might have been a confounding factor anyway.

After borrowing a wading pool from some neighbors, I retreated to the basement for the guppy time trials ... which failed miserably. The fish just swam around. There was no real trend, and I didn't really have time to make sure the guppies got hungry again in between searches, so who knows what they were looking for.

The whole experience (which, I should add, followed a project earlier in the semester for which I chased squirrels around a campus lawn trying to monitor their nut-caching behavior) convinced me that trying to make quantitative measurements of animal behavior was impossible, or at the very least would lead to several decades in graduate school waiting for animals to get hungry again.

So that's why I took note that the Jones' groups fish time trials come out so cleanly... I guess I should have realized that all those animal research journals weren't just reporting on aimless guppy wandering, so there must be better observations to be made. Still, it's great that this group for found such opinionated fishes.

(Video: Jelle Atema, Boston University)

Organic Motivations

CNN carried a story about a study concluding that organic produce does not contain more nutrients than the same five fruits and veggies (carrots, kale, mature peas, apples and potatoes) conventionally grown.

That is certainly a bummer for the organic food industry, which would no doubt like to make nutrition claims about the food. But, Michaeal Pollan, in The Omnivore's Dilemma, cites a similar 2003 UC Davis study that found corn, strawberries and blackberries grown organically had more vitamin C and polyphenols than conventionally grown ones in neighboring plots. So, does it vary from plant to plant, place to place, or is something else going on?

More to the point, I don't think most people buy organic food because they believe it has more vitamins. I think they do it because they don't want to risk eating food with any pesticide residues. They may also do it because they want to reduce the amount of pesticides and petrochemical fertilizer entering the environment, or because they want to support agricultural practices in which the workers aren't exposed to such chemicals.

As with so many things, though, organic farming is not an across-the-board win. Sigh. The CNN story mentions a 2006 report by the University of Manchester Business School investigating the environmental impacts of food. While organic food used less pesticide, the land requirements were often greater--presumably because the crop yield was reduced.

The energy requirements for organic milk were less than conventional, but the land use was greater, and the greenhouse gas emissions per gallon were higher for organic. And, according to the study summary, "organic wheat production has higher impact than non-organic," mainly because its eutrophying emissions are higher.

This is just one example of why shopping these days is such a paralyzing experience: when choosing which apple to buy becomes a trade off between deforming the local frogs or drowning the polar bears, it feels easier to go hungry.

Fortunately, Consumer Reports offers some advice on which fruits and veggies are worth buying organic--at least from a pesticide perspective.

(Image: Flickr user Scoobymoo. Some rights reserved.)

Getting There Sans Car

While we're on the subject of walking, this week Google launched a version of Google maps for pedestrians. If you ask for directions to a spot less than 6.2 miles away, Google will now give you the option to select directions for going either by car or walking.

When I tried it, Google gave me a shorter route for walking to the University of Minnesota from my house than for driving, but certainly not a more pleasant one, sending me down a very busy street instead of along the river (which is about a half-mile longer). It looks like even when less-trafficked routes are equally direct, it picks a major street. But at least it won't send you on the freeway.

Meanwhile, here's a Google-maps-based cycling map created for the Vancouver, B.C. area. You can choose whether or not you want to include major streets in your route, and you can select whether you want to take the path with the least elevation gain, the most vegetation, the shortest distance, the least traffic pollution, or if you want to require that your route have no spots along the way that are steeper than a slope of your choice. Once it marks your way, the path is color coded to indicate the hilly parts.

In addition to telling you how far the route is and how long it's likely to take you, the site tells you the amount of  greenhouse gases you avoided by biking instead of driving, the mean nitrogen oxide concentration along the route, and how many calories you burned. I want one for the Twin Cities.

There's a push for more tools like this. Here's an AP story with some more info on efforts in other places.

(Image: From Cycle Vancouver)

How Walkable Is Your 'Hood?

Today Discovery News highlighted research showing that the more your neighborhood allows or encourages you to walk, the less you are likely to weigh.

So if you're looking to slim down and you've decided moving is cheaper than joining a gym (it is more likely to stick), Walk Score can help you pick the most walkable parts of any of the country's largest 40 cities. I'm a bit disappointed that Minneapolis-St. Paul is not on the list, because the two cities are counted separately and neither makes the top 40 on its own.

But if you live in Milwaukee, Cleveland, or 38 other cities, you can see a map and list of the most walkable neighborhoods in town.

According to Lawrence Frank of the University of British Columbia, Walk Score uses distance to many destinations to determine walkability, which has limitations. "You could be right near a mall, and you could be on the end of the culdesac and not be able to get to the mall," he said.

So, that's just to say that you shouldn't buy a house without visiting it first and making sure you really can walk where you want to. Indeed, Walk Score suggests this and notes its own limitations. But the site has some pretty nice maps and it's certainly better than nothing.

Check out America's most walkable neighborhoods.

Do you live in one? Does a walkable lifestyle make your life or health better?

(Image: Flickr user Atilla1000, some rights reserved.)

Geiger Countertop

According to a New York Times article, your granite countertop may be a hot commodity. Literally.

It turns out that granite countertops emit radiation including radon--the radioactive gas resulting from the breakdown product of uranium within. The vast majority of granite countertops emit far less than the background radiation we're exposed to all the time.

But, a few countertops have been found to have relatively high levels of radiation--some more than 100 times background. (Even countertops emitting above background are unlikely to cause cancer, according to the Times.)

What struck me about this story was not the possible slight increased cancer risk from a granite countertop, but the following:

"The E.P.A. recommends taking action if radon gas levels in the home exceeds 4 picocuries per liter of air (a measure of radioactive emission); about the same risk for cancer as smoking a half a pack of cigarettes per day."

The recommended action level equates to 10 cigarettes per day? Given how widespread smoking bans are these days, I'm surprised there isn't more of a push to keep our basements from being the radon equivalent of a restaurant smoking section. Then again, who said these processes were rational?

P.S. I noticed that Larry O'Hanlon also posted about this article at his Earth Impacts blog. Check it out.

(Image: Flickr user Kyknoord, some rights reserved.)

Shuffling Species

As the climate warms, many species may no longer be comfy in their habitats and become better suited to survival at higher latitudes or higher elevations where they can escape the heat. But how is a tree species that takes decades to reproduce going to migrate fast enough to keep pace with a rapidly changing climate? What if a major city lies between a critter's old habitat and where it needs to go to survive?

We might help. That's the idea behind "assisted colonization"--deliberately moving plants or animals from places where they're doomed to places where they might survive in the future. In today's issue of Science, a group of researchers published an article saying this is an approach we should take seriously. Read an article about it at Discovery News.

It's a horrifying prospect to some conservation biologists. They point to the long list of species introduced into new habitats by humans (like moving cane toads to Australia) that have gone terribly wrong. The authors of the new report agree that some introductions would be risky and should be avoided: moving polar bears from the Arctic to Antarctica would introduce a predator of penguins and seals and likely decimate those populations.

But other introductions seem less likely to cause a disruption. Most would be regional moves, not inter-continental. The authors point out that staghorn corals currently live over a range of latitudes and that those at low latitudes can tolerate higher temperatures than the ones further from the equator. Moving low-latitude coral into higher latitudes where cold-adapted corals are already dying off is unlikely to cause a problem, the authors argue.

The researchers discuss assisted colonization as a way to save species from extinction, but there might be other motivations.

For instance, here in Minnesota, we are at the southern tip of the spruce-fir forest range, which is likely to retreat into Canada in a warming climate, and our deciduous forests face threats, too. But having forests in the state is a big part of its identity. Can we be happy knowing that the forests exist to the north and learn to live without them here? Or, should we bring in trees from further south that will thrive in our new climate and keep us under a forest canopy?

It's not just a psychological issue: forests contribute to our industrial and recreational economy, so people may be reluctant to let the woods give way to savanna. Check out an earlier post about a conference here where they discussed the topic.

What do you think? Is this a good idea? When would you be willing to give a species a helping hand? Or, should we let nature take its course... whatever that means in today's world?

(Image: Flickr user *Micky, some rights reserved)

A Test

Here's an awareness test to try for fun. You can check out the home site here. If you're interested in the subject, here's a related post.

More Math at $4 a Gallon

I wrote a couple of weeks ago about one way that $4 a gallon gasoline might get us looking at things differently.

It is interesting to see stories emerging about other ways that fuel at $4 a gallon is causing changes.

First, Reuters had a story late last week about how home buyers are abandoning the 'burbs in favor of cities, partly driven by the higher fuel prices. The article mentions a survey of realtors, 80 percent of whom reported that higher fuel costs are making buyers more interested in living in cities.

The New York Times ran a story a couple of weeks ago with a similar message. It says:

In 2003, the average suburban household spent $1,422 a year on gasoline, according to the Bureau of Labor Statistics. By April of this year -- when gas prices were about $3.60 a gallon-- the same household was spending $3,196 a year, more than doubling consumption in dollar terms in less than five years.

Meanwhile high oil prices effect more than just fuel. Petroleum provides the raw materials for making plastics, paints, adhesives, soaps, fibers, pharmaceuticals and more. Just as people are looking for alternatives to using petroleum for fuel, others are trying to obtain the carbon molecules necessary to make this array of products from renewable sources.

Plastic made from corn is one example, and DuPont is making a fiber that comes partly from corn that it is using in carpets.

Of course, the expense of these alternative products has been an obstacle, because commodity chemicals derived from oil have been cheap, cheap relative to developing new, bio-based materials. But, as a Cargill executive told me when I spoke with him more than a year ago, "When you have 75 dollar a barrel oil, a lot of things can happen."

That threshold seems a quaint memory now, and the chemical industry is feeling the heat. Dow announced price hikes of up to 25 percent on commodity chemicals a couple of weeks back.

So, by the executive's estimation, bio-based processes ought to be looking pretty good. And, one researcher told me, because the amount of carbon needed for chemicals is just a teeny trickle compared with what's needed for fuels, sending some biomass to chemical processes to make plastics and other non-fuel applications should not create the competition for food that we're seeing with corn-derived ethanol and other biofuels.

(Image: Flickr user KB35, some rights reserved.)

Smog Blog

Wildfires have been ripping through the west, and while they endanger homes and may or may not be good for the natural habitats they burn, they are definitely bad for the air quality.

The Smog Blog tracks air quality nationwide on a daily basis with satellite data, lidar, EPA pollution-monitoring networks, and more, compiled by the University of Maryland, Baltimore County Atmospheric Lidar Group. The team provides lots of maps showing clouds, smoke, particle levels, ozone levels, etc.

In recent days the emphasis has been on the wildfires in California. Plumes of smoke are easily seen from satellite images. They suggest the huge scale of the fire, but don't do justice to the havoc much closer to the ground.

Check out the maps and the air quality near you.

 

(Image: Measurements of particles < 2.5 microns shown over California. Maroon points near Auburn, Sacramento, Roseville-Rocklin and Bakersfield show hazardous levels, overlaid on true color satellite image. Image obtained from the U.S. Air Quality Smog Blog.)