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Forests are growing faster, climate change most likely new steroid

Monday, February 1st, 2010

SERC woods during wintertime

Liriodendron tulipifera, or tulip poplar, is a common tree in the temperate forests surrounding the Smithsonian Environmental Research Center. Other species include sweetgum, American beech, and southern red oak. Photo: Kirsten Bauer.

Speed is not a word typically associated with trees; they can take centuries to grow. However, a new study to be published the week of Feb. 1 in the Proceedings of the National Academy of Sciences has found evidence that forests in the Eastern United States are growing faster than they have in the past 225 years. The study offers a rare look at how an ecosystem is responding to climate change.
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This little orchid prefers winter

Friday, January 8th, 2010

Forget about a tree growing in Brooklyn, there’s an orchid growing in the snow. Its name is Aplectrum hyemale. It’s a clever and contrarian little thing.

Aplectrum hyemale

The orchid Aplectrum hyemale is not afraid of a little snow. Winter is the perfect time for it to photosynthesize.

Aplectrum hyemale waits until the fall to unfurl a solitary leaf. It’s an ellipse of broad green with thin cream stripes. The plant sits low to the ground. In the summertime it would have to compete like crazy for an ounce of sunlight. And it would likely lose out to oaks, tulip trees and the like. During the winter though, after the forest canopy has been stripped bare, Aplectrum hyemale can get all the rays it needs. So a winter green it is.
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A free trip to the Caribbean

Wednesday, December 23rd, 2009

Yesterday we gave you a glimpse of Saudi Arabia’s mangroves. Today we offer you free passage to the Caribbean. Smithsonian Environmental Research Center senior scientist Ilka “Candy” Feller organized this virtual tour of Mangal Cay, a mangrove island in the tropics. You can journey with her through the forests and underwater to learn more about the ecology of mangroves. This virtual tour was supported by the National Science Foundation. Click the image below to start the voyage.

Mangrove Tour Image

The tour’s also available in Spanish. Happy travels.

Climate change may drastically alter Chesapeake Bay, scientists say

Thursday, December 3rd, 2009

Smithsonian researchers Lori Davias and Jenna Malek collect oysters on an intertidal reef in the Chesapeake Bay. It is difficult to predict the effect of climate change on oyster populations because increasing temperatures will likely have at least two opposing effects. On one hand, intertidal oyster populations may be able to expand northward as winter temperatures rise. On the other hand, increasing summer temperatures are likely to worsen the problem of low oxygen concentrations and may reduce the extent or suitability of some subtidal habitat currently used by oysters. At this point, scientists are unable to predict whether the combination of these two factors will result in a net increase or net loss of habitat.  Photo: Sean Fate

Smithsonian researchers Lori Davias and Jenna Malek collect oysters on an intertidal reef in the Chesapeake Bay. It is difficult to predict the effect of climate change on oyster populations because increasing temperatures will likely have at least two opposing effects. On one hand, intertidal oyster populations may be able to expand northward as winter temperatures rise. On the other hand, increasing summer temperatures are likely to worsen the problem of low oxygen concentrations and may reduce the extent or suitability of some subtidal habitat currently used by oysters. At this point, scientists are unable to predict whether the combination of these two factors will result in a net increase or net loss of habitat. Photo: Sean Fate

It is one of the largest and most productive estuaries in the world, yet dramatic changes are in store for the Chesapeake Bay in coming decades if climate change predictions hold true, say a team of scientists from the Smithsonian Environmental Research Center, the University of Maryland, Pennsylvania State University, and other research organizations in a recent paper published in the journal “Estuarine, Coastal and Shelf Science”

Using forecasts of atmospheric carbon dioxide production for the coming century, the scientists predict the water of the Bay will see rising levels of dissolved carbon dioxide and higher water temperatures. As a result, climate change is expected to worsen problems of low dissolved oxygen concentrations in the Chesapeake’s water and cause sea levels to rise.
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Happy 150th ‘Origin of Species’

Tuesday, November 24th, 2009

On this day in 1859, Darwin went public with his case for the theory of natural selection. The arguments he set forth in The Origin of Species, have guided scientific explorations of evolution ever since. The biologists and ecologists here at the Smithsonian Environmental Research Center apply Darwin’s theory perhaps as much as they do soap. They may use modern genetics to investigate rare orchids, blue crabs and parasitic dinoflagellates – but Darwin’s discoveries continue to influence their research.

"The Origin of Species" may be 150 years old, but it can still hold its own in the Smithsonian’s research labs.

'The Origin of Species' may be 150 years old, but it can still hold its own in the Smithsonian’s research labs.

To mark the anniversary of Darwin’s landmark publication, here are two passages from the book; the first is from the introduction, the second is from the final page.

No one ought to feel surprised at much remaining as yet unexplained in regard to the origin of species and varieties, if he make due allowance for our profound ignorance in regard to the mutual relations of the many beings which live around us. Who can explain why one species ranges widely and is very numerous, and why another allied species has a narrow range and is rare? Yet these relations are of the highest importance, for they determine the present welfare and, as I believe, the future success and modification of every inhabitant of this world. Still less do we know of the mutual relations of the innumerable inhabitants of the world during the many past geological epochs in its history. Although much remains obscure, and will long remain obscure, I can entertain no doubt, after the most deliberate study and dispassionate judgment of which I am capable, that the view which most naturalists until recently entertained, and which I formerly entertained—namely, that each species has been independently created—is erroneous. I am fully convinced that species are not immutable; but that those belonging to what are called the same genera are lineal descendants of some other and generally extinct species, in the same manner as the acknowledged varieties of any one species are the descendants of that species. Furthermore, I am convinced that Natural Selection has been the most important, but not the exclusive, means of modification.

It is interesting to contemplate a tangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent upon each other in so complex a manner, have all been produced by laws acting around us. These laws, taken in the largest sense, being Growth with Reproduction; Inheritance which is almost implied by reproduction; Variability from the indirect and direct action of the conditions of life, and from use and disuse: a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less-improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.

Listen to the recent broadcast of PRI’s Studio 360 for a look at the cultural impact of Darwin’s book.

‘Tidal Freshwater Wetlands’ gives an overlooked ecosystem its due

Tuesday, November 17th, 2009

Tidal Freshwater Wetlands book cover

Tidal Freshwater Wetlands

There are certain obstacles you have to embrace if you are going to edit a book about tidal freshwater wetlands. They include: mud, mosquitoes and leeches. Smithsonian plant ecologist Dennis Whigham has accepted all three and then some.

Whigham, along with colleagues Aat Barendregt from Utrecht University and Andy Baldwin from the University of Maryland, has edited the new book Tidal Freshwater Wetlands. It’s a weighty work containing more than 20 chapters written by more than 40 authors. For the first time ever, they have systematically peeled back the layers of these overlooked coastal ecosystems. The book explores how these wetlands work, the animal and plant life they support, and the threats they face.
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