Tag Archives: pollen

Pollen and clouds: April flowers bring May showers?

ANN ARBOR — The main job of pollen is to help seed the next generation of trees and plants, but a new study from the University of Michigan and Texas A&M shows that the grains might also seed clouds. (more…)

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Fleischfressende Pflanze auch vegetarisch glücklich

Auch Pflanzen profitieren von ausgewogener Ermährung

Der Trend zur fleischlosen Ernährung macht auch vor Pflanzen nicht halt: Wie eine ForscherInnengruppe um Marianne Koller-Peroutka und Wolfram Adlassnig von der Universität Wien herausfand, ernährt sich der Wasserschlauch, eine Wasserpflanze, die auch in vielen österreichischen Seen und Tümpeln zu finden ist, nicht nur von kleinen Wassertieren, sondern auch von Algen und Blütenpollen. Damit kann er nicht nur in Gewässern überleben, wo Tiere sehr selten sind – auch bei erfolgreicher Jagd auf tierische Beute profitieren die Pflanzen von einer ausgewogenen, algenreichen Ernährung. Die Ergebnisse der Studie wurden soeben in der renommierten Zeitschrift “Annals of Botany” veröffentlicht. (more…)

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Allergikern blüht etwas: Erhöhte Fitness der Beifußambrosie in Europa nachgewiesen

Die ursprünglich aus Amerika stammende hochallergene Beifußblättrige Ambrosie entlässt ihre Pollen bis in den späten Herbst hinein und verlängert damit die Leidensphase von Allergikern erheblich. Das Gewächs ist in Deutschland auf dem Vormarsch. Ein Team des LOEWE Biodiversität und Klima Forschungszentrums und der Goethe-Universität Frankfurt zeigte jetzt in einer im Fachjournal Oecologia veröffentlichten Studie, dass sich die europäischen Populationen der invasiven Art weiterentwickelt und an Durchsetzungskraft gewonnen haben. In einer zweiten, in der Fachzeitschrift Biological Invasions publizierten Studie zeigt sich eine große phänotypische Variabilität der Art, die ebenfalls die weitere Ausbreitung befördern könnte. Eine nationale Strategie zur Bekämpfung der Art tut also not.

Während das unscheinbare Kraut mit dem wissenschaftlichen Namen Ambrosia artemisiifolia in Deutschland noch vergleichsweise selten vorkommt, ist es im Südosten Europas schon fester Bestandteil der Vegetation. Als Spätblüherin setzt die Ambrosie ihre Pollen erst im Spätsommer und lange bis in den Herbst hinein frei. Das bedeutet für Allergiker eine Verlängerung ihrer Leidenszeit bis in den Oktober hinein, bei warmen Wetterverhältnissen sogar bis in den Dezember. Die Pollen sind zudem erheblich aggressiver als die hiesiger Gräser und Bäume. Entsprechend hoch wäre die Zahl der Erkrankungen, wenn sich die Ambrosie auch in Deutschland ausbreiten würde, wie es frühere Studien nahelegen. (more…)

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Evolution, Civil War History Entwine in Fossil Find

COLLEGE PARK, Md. – A fossil leaf fragment collected decades ago on a Virginia canal bank has been identified by a University of Maryland doctoral student as one of North America’s oldest flowering plants, a 115- to 125-million-year-old species new to science. The fossil find, an ancient relative of today’s bleeding hearts, poses a new puzzle in the study of plant evolution: did Earth’s dominant group of flowering plants evolve along with its distinctive pollen? Or did pollen come later?

The find also unearths a forgotten chapter in Civil War history reminiscent of the film “Twelve Years a Slave,” but with a twist. In 1864, Union Army troops forced a group of freed slaves into involuntary labor, digging a canal along the James River at Dutch Gap, Va. The captive men’s shovels exposed the oldest flowering plant fossil beds in North America, where the new plant species was ultimately found. (more…)

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Study Provides New Insights on Drought Predictions in East Africa

Research May Also Help Determine Effects of Global Warming in the Region

With more than 40 million people living under exceptional drought conditions in East Africa, the ability to make accurate predictions of drought has never been more important. In the aftermath of widespread famine and a humanitarian crisis caused by the 2010-2011 drought in the Horn of Africa—possibly the worst drought in 60 years— researchers are striving to determine whether drying trends will continue.

While it is clear that El Niño can affect precipitation in this region of East Africa, very little is known about the drivers of long-term shifts in rainfall. However, new research described in the journal Nature helps explain the mechanisms at work behind historical patterns of aridity in Eastern Africa over many decades, and the findings may help improve future predictions of drought and food security in the region. (more…)

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Public Acceptance of Climate Change Affected by Word Usage, Says MU Anthropologist

Better science communication could lead to a more informed American public.

Public acceptance of climate change’s reality may have been influenced by the rate at which words moved from scientific journals into the mainstream, according to anthropologist Michael O’Brien, dean of the College of Arts and Science at the University of Missouri. A recent study of word usage in popular literature by O’Brien and his colleagues documented how the usage of certain words related to climate change has risen and fallen over the past two centuries. Understanding how word usage affects public acceptance of science could lead to better science communication and a more informed public.

“Scientists can learn from this study that the general public shouldn’t be expected to understand technical terms or be convinced by journal papers written in technical jargon,” O’Brien said. “Journalists must explain scientific terms in ways people can understand and thereby ease the movement of those terms into general speech. That can be a slow process. Several words related to climate change diffused into the popular vocabulary over a 30-50 year timeline.” (more…)

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Brown and High Schools: Teaching Teens About Climate Change, Health

A Brown University class on the effect that climate change could have on human health has produced a free new curriculum for high school teachers. The nine-module unit, which reflects feedback from teachers, includes lecture background and ideas for warm-ups, in-class activities, and assessment.

PROVIDENCE, R.I. [Brown University] — Katherine Smith’s students had to wait until they came to Brown University to learn how climate change could affect human health. Now that Smith and her fall semester class have developed a rich new curriculum on the subject for high school teachers, future 10th to 12th graders might not have to wait so long.

The curriculum, a nine-module set of backgrounders, lecture notes and suggested lesson plans and classroom activities, is now available for free download. In 180 total pages, it covers topics ranging from an overview of climate change to more specific units such as how global warming could affect infectious disease, allergies, and the global food supply. (more…)

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Climate and Drought Lessons from Ancient Egypt

Using Fossil Pollen to Augment Historical Records

Ancient pollen and charcoal preserved in deeply buried sediments in Egypt’s Nile Delta document the region’s ancient droughts and fires, including a huge drought 4,200 years ago associated with the demise of Egypt’s Old Kingdom, the era known as the pyramid-building time.

“Humans have a long history of having to deal with climate change,” said Christopher Bernhardt, a researcher with the U.S. Geological Survey. “Along with other research, this study geologically reveals that the evolution of societies is sometimes tied to climate variability at all scales – whether decadal or millennial.” (more…)

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