Archive for December, 2008

Brain Food

Wednesday, December 24th, 2008

Just in time to assuage the guilt of holiday indulgers, a new study in the Journal of Nutrition suggests that chocolate and wine enhance cognitive performance. According to Oxford researchers working with colleagues in Norway, study participants who consumed chocolate and wine as well as tea had significantly better test scores than those who did not. The brain benefits are attributed to polyphenols, micronutrients found in plant foods, especially flavonoids. Wine produced the biggest benefits.

Photosynthetic Machines

Wednesday, December 17th, 2008

In twenty years, according to Department of Energy Secretary nominee Steven Chu, artificial leaf-like membranes mimicking plant photosynthesis will be converting sunlight into liquid fuels. Right now, the transportation sector is almost entirely dependent on gasoline, diesel, and other petroleum-based fuels. In 2003 it accounted for about 27 percent of total U.S. greenhouse gas emissions.

Green Walls or Greenwash?

Tuesday, December 16th, 2008

I admit it—I’m as seduced by the idea of verdant buildings as the next plant nut. On a purely aesthetic level, structures with living walls are a major improvement over the granite and glass monoliths that rise from the typical cityscape like enormous gravestones. But before we fall head over heels for green walls it’s worth asking whether they’re all they’re cracked up to be. Do they really, as touted, help insulate buildings, filter particulates from polluted city air, counteract the urban heat island effect, and create habitat for insects and spiders? Or are they just a green veneer, a 21st-century version of the fussy millwork that decorated Victorian buildings? Or worse, do they actually eat up more resources than they save? 

Even the green-minded bloggers at Treehugger and Inhabitat have been drooling over the latest designs, Daniel Libeskind’s 900-foot New York Tower, an upscale residential skyscraper with a section of glass curtain wall cut away to accommodate vegetated balconies, and Rotterdam-based MVRDV’s cluster of cone-like structures with concentric rings of boxwood-lined terraces intended for a new city south of Seoul. From a biological point of view, only one of the “11 Buildings Wrapped in Gorgeous Green and Living Walls” in this glowing review is interesting—Sharp & Diamond’s 50-square-meter green wall of wildflowers, ferns, and ground covers at the Vancouver Aquarium that seems to be based on plant associations found on cliffs, scree slopes, and other natural analogs. (If you haven’t seen it, take a look at The Urban Cliff Revolution, which suggests that these natural habitats have a lot in common with skyscrapers and other features of the modern city, and can serve as “habitat templates” for green walls and roofs.)

But what about the carbon footprint of the growing media used to create green walls, and any fertilizers used to sustain the plants? Is irrigation required? If so, is there an integrated graywater system in which used water from sinks, dishwashers, and other sources is cleansed by the plants and growing medium and piped back into the building to flush toilets? In short, do the environmental benefits of green walls outweigh the costs? I’d love to see some hard data.

Millennium Seed Bank — Another Bank in Trouble

Monday, December 15th, 2008

Royal Botanic Gardens, Kew’s Millennium Seed Bank is having financial troubles, according to the BBC. The MSB is on track to bank seeds of 10 percent of the world’s wild flowering plants by the end of this decade, but it’s facing a 100 million pound shortfall for its goal of banking 25 percent of the Earth’s plants over the next ten years. It was established in 2000 to collect and bank seeds of all the planet’s plants as an insurance policy — an important effort, given that an estimated 100,000 plant species are in peril.

You can support the MSB with an online donation.

Eye to Eye

Saturday, December 13th, 2008

In Martin Amm’s photography, reality Is more fabulous than science fiction: See here and here and here. The side views of insects bejeweled in morning dew are pretty spectacular, too. Be sure to click on the photos to enlarge them.

Will Somebody Please Adopt This Tree?

Friday, December 12th, 2008

This year there seem to be more Fraser firs than ever for sale in my neighborhood, the Upper West Side of Manhattan. No big surprise. Woody plant expert Michael Dirr once called them the “Cadillac of Christmas Trees.” Fraser firs have a gorgeous pyramid shape and a profusion of soft, short needles arranged spirally around the branches. They also smell great. 

What is shocking is the stark contrast between the countless Fraser firs that line city streets, lending a festive air during the holidays, and the gray skeletons found in the tree’s native habitat. The species is endemic to the seven highest peaks in North Carolina, Tennessee, and Virginia; it is found nowhere else in the world. But in the past fifty years the number of mature Fraser firs on these mountains has declined by as much as 91 percent. The species is threatened with extinction in the wild largely because of an introduced insect, the balsam wooly adelgid, which first appeared in the southern Appalachians in 1957. The insect attacks by entering the trunk of a tree through fissures in its bark that develop as it ages; two to seven years later, the tree is dead.

Another threat to the Fraser fir: As temperatures rise due to global warming, it has nowhere to go. It can’t migrate upward to cooler, higher habitat because it already grows at high elevations on those seven mountains, in forests believed to be ice age relicts. When the last of the Pleistocene glaciers retreated north, Fraser fir was left stranded on these mountaintops, which have climates similar to those of Maine and Quebec. 

Someday it may be possible to see Fraser fir only on Christmas tree farms, or frigid Gotham streets.

The species is in the National Collection of Endangered Plants, under the auspices of the Center for Plant Conservation, a coalition of botanical gardens. But Fraser fir deserves to live wild and free, outside the cultivated confines of a farm, a garden collection, or a seed bank. For a number of years, the National Park Service reportedly tried to control the balsam wooly adelgid at Clingman’s Dome in Tennessee, using the only effective control known to date — coating each limb of each tree with a mild soap. But this proved too time consuming and costly and was given up.

Scientists and government officials have their hands full with invasive pests and imperiled plants, not to mention budget cuts and a host of other impediments. But citizens can fill the gap. Another endangered native conifer, the Florida torreya, has a group of activists, the Torreya Guardians, advocating and acting on its behalf. Friends of the Fraser fir anyone?

First-Ever Vertical Farming Summit

Tuesday, December 9th, 2008

This weekend in Berkeley, experts from a variety of disciplines including architecture, structural engineering, greenhouse growing, composting, alternative energy, aquaculture, hydroponics, integrated biological systems, sustainable farming, and urban agriculture are meeting for the first summit on vertical farming in urban areas, also rather inelegantly known as building-integrated sustainable agriculture.

The summit’s co-organizers are Keith Agoada and James Kalin, founder and technical director, respectively, of Sky Vegetables, launched by Agoada to build hydroponic greenhouses on the rooftops of grocery stores. A list of presenters and presentations will be posted on the Sky Vegetables website at the close of the conference. Their prototype system is featured on the site. 

Evolutionary Biology Over Animatronic Religious Mythology?

Tuesday, December 2nd, 2008

A web campaign has scuttled a joint promotional deal launched last week by the Cincinnati Zoo and Botanical Garden and the Creation Museum, which promotes a strict interpretation of the biblical version of how life began.