(Press-News.org) MANHATTAN, KAN. -- A collaborative project involving a Kansas State University ecologist has shown that the Clean Air Act has helped forest systems recover from decades of sulfur pollution and acid rain.
The research team -- which included Jesse Nippert, associate professor of biology -- spent four years studying centuries-old eastern red cedar trees, or Juniperus virginiana, in the Central Appalachian Mountains of West Virginia. The region is downwind of the Ohio River Valley coal power plants and experienced high amounts of acidic pollution -- caused by sulfur dioxide emissions -- in the 20th century.
By studying more than 100 years of eastern red cedar tree rings, the scientists found that the trees have improved in growth and physiology in the decades since the Clean Air Act was passed in 1970.
"There is a clear shift in the growth, reflecting the impact of key environmental legislation," Nippert said. "There are two levels of significance in this research. One is in terms of how we interpret data from tree rings and how we interpret the physiology of trees. The other level of significance is that environmental legislation can have a tremendous impact on an entire ecosystem."
The findings appear in the scientific journal Proceedings of the National Academy of Sciences of the United States of America, or PNAS, in the article "Evidence of recovery of Juniperus virginiana trees from sulfur pollution after the Clean Air Act."
The principal investigator on the project was Richard Thomas, professor of biology at West Virginia University. Other researchers include Scott Spal, master's graduate from West Virginia University, and Kenneth Smith, undergraduate student at West Virginia University.
For the study, the scientists collected and analyzed data from eastern red cedar trees ranging from 100 to 500 years old. The researchers wanted to better understand the trees' physiological response and the growth response to long-term acid deposition, or acid rain.
The team focused on red cedar trees because they are abundant, long-lived and a good recorder of environmental variability. Red cedar trees grow slowly and rely on surface soil moisture, which makes them sensitive to environmental change. Their abilities to live for centuries meant that researchers could analyze hundreds of years of tree rings, Nippert said.
The researchers analyzed the stable carbon isotopes within each tree ring as a recorder of physiological changes through time. Nippert's Stable Isotope Mass Spectrometry Laboratory at Kansas State University analyzed the samples. Researchers analyzed tree rings back to the early 1900s, when sulfur dioxide deposition throughout the Ohio River Valley began to increase.
By studying the stable isotopic signature in each tree ring, the researchers were able to compare the trees' growth patterns and changes in physiology to changes in atmospheric chemistry during the 20th century. Results showed that despite increased carbon dioxide -- which tends to increase plant growth -- tree growth and physiology declined for the majority of the 20th century when acidic pollution was high.
But scientists noticed a dramatic change around 1980, 10 years after the Clean Air Act was enacted.
"Our data clearly shows a break point in 1982, where the entire growth patterns of the trees in this forest started on a different trajectory," Nippert said. "It took 10 years for that landmark environmental legislation to reduce sulfur dioxide emissions, but it eventually did. When it did, we saw an entire ecosystem recover from years of acidic pollution."
Another interesting finding from the tree ring analysis: Results from the Great Depression era in the 1930s were very similar to the results from post-1980. Because of the suppressed economy during the Great Depression, coal power plants were less productive and the Ohio River Valley had reduced fossil fuel emissions. Similar to the post-1980 data, data from the 1930s showed improved tree growth and physiology.
"It's kind of interesting that those two very important periods in our history match up perfectly in terms of the responses seen throughout this whole forest ecosystem," Nippert said.
INFORMATION: END
Scientists estimate that there is a minimum of 320,000 viruses in mammals awaiting discovery. Collecting evidence of these viruses, or even a majority of them, they say, could provide information critical to early detection and mitigation of disease outbreaks in humans. This undertaking would cost approximately $6.3 billion, or $1.4 billion if limited to 85% of total viral diversity -- a fraction of the economic impact of a major pandemic like SARS.
Close to 70% of emerging viral diseases such as HIV/AIDS, West Nile, Ebola, SARS, and influenza, are zoonoses -- infections ...
NEW YORK – September 3, 2013 – EcoHealth Alliance, a nonprofit organization that focuses on local conservation and global health issues, and the Center for Infection and Immunity (CII) at Columbia University's Mailman School of Public Health announced a new strategy to identify the total number of wildlife viruses that could potentially cause emerging disease outbreaks that threaten both public and wildlife health. Combining field investigations with a new statistical approach, scientists estimate that there may exist a minimum of 320,000 viruses awaiting discovery from ...
Researchers from major universities in the U.S. have developed specific tests to identify cancer biomarkers in patients with dermatomyositis—a systemic inflammatory disease associated with increased risk of malignancy. According to study findings published in the American College of Rheumatology (ACR) journal, Arthritis & Rheumatism, the assays detect antibodies against anti-transcriptional intermediary factor-1 (TIF-1γ) and nuclear matrix protein NXP-2.
Patients with dermatomyositis experience muscle weakness, skin inflammation, and sometimes inflammation of the ...
Consistently uniform, easily manufactured microcapsules containing a brain cancer drug may simplify treatment and provide more tightly controlled therapy, according to Penn State researchers.
"Brain tumors are one of the world's deadliest diseases," said Mohammad Reza Abidian, assistant professor of bioengineering, chemical engineering and materials science and engineering. "Typically doctors resect the tumors, do radiation therapy and then chemotherapy."
The majority of chemotherapy is done intravenously, but, because the drugs are very toxic and are not targeted, ...
ARLINGTON HEIGHTS, ILL. -- Asthma is a disease that mostly affects young boys and adult women. And according to a new study, women in their 40s and 50s with asthma are hospitalized more than twice as often as men in the same age group. The 10-year study is published in the September issue of Annals of Allergy, Asthma & Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology (ACAAI).
"Until puberty, boys have higher rates of asthma than girls," said Robert Yao-wen Lin, MD, allergist and lead study author. "Then, during the menopausal ...
LOS ANGELES — Teenagers who see friends smoking and drinking alcohol in photographs posted on Facebook and Myspace are more likely to smoke and drink themselves, according to a new study from the University of Southern California (USC).
"Our study shows that adolescents can be influenced by their friends' online pictures to smoke or drink alcohol," said Thomas W. Valente, Ph.D., professor of preventive medicine at the Keck School of Medicine of USC and the study's principal investigator. "To our knowledge, this is the first study to apply social network analysis methods ...
Amsterdam, The Netherlands – Tuesday 3 September 2013: Low BMI is a risk factor for CVD in hypertensive patients with diabetes, according to research presented at the ESC Congress today by Dr Takanori Nagahiro from Japan. The findings provide evidence for an obesity paradox in hypertensive patients with glucose intolerance.
Dr Nagahiro said: "Obesity is a risk factor for cardiovascular disease (CVD) but several studies have reported that low body mass index (BMI, kg/m2) was associated with worse cardiovascular outcome compared to middle or higher BMI. This strange phenomenon ...
What do lotus flowers, soap bubbles, and aerated chocolate have in common? They may seem innocuous, even pleasant, but each of these items is a trigger for people who report suffering from trypophobia, or the fear of holes. For trypophobes, the sight of clusters of holes in various formations can cause intensely unpleasant visceral reactions.
New research from psychological scientists Geoff Cole and Arnold Wilkins of the University of Essex suggests that trypophobia may occur as a result of a specific visual feature also found among various poisonous animals. The findings ...
Chevy Chase, MD—Researchers have developed the first animal model simulating the eye complications associated with the thyroid condition Graves' disease, a breakthrough that could pave the way for better treatments, according to a recent study accepted for publication in The Endocrine Society's journal Endocrinology.
Graves' disease is an autoimmune disorder that causes the body to produce antibodies that attack the thyroid gland. The condition causes the thyroid gland to become overactive and produce too much thyroid hormone. If left untreated, it can lead to heart failure ...
CAMBRIDGE, Mass. (September 3, 2013) – Unlike humans, planarian flatworms have the remarkable ability to regrow any missing body part, making them an ideal model with which to study the molecular basis of regeneration.
Over the years scientists have learned that planarians mount recovery responses that differ depending on the severity of the injury they suffer. For example, a worm with a cut or a puncture wound reacts at the cellular and molecular levels quite differently from one that loses its head or tail. What has remained unclear, however, is just exactly how these ...
