Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Trees may contribute to ozone problem

26.06.2002


Trees may not actually commit suicide, but certain species do produce pollutants that hamper their own growth while contributing to global climate changes and causing harm to other life forms, contend two Texas A&M University researchers.



Renyi Zhang, an atmospheric chemist, is studying one such substance, isoprene, given off by oak trees and leading to increased ozone in our atmosphere. Working under a $300,000 grant from the National Science Foundation, Zhang and chemistry professor Simon North have taken on the challenge of unraveling the more than 1,000 reactions that transform organically released isoprene into toxic atmospheric pollutants.

"Air pollution is probably one of the most serious problems facing humankind in the 21st century," said Zhang, a professor in the College of Geosciences. "And certainly, much of that pollution results from human activities. But most people are not aware of the role played by chemical reactions which change substances produced by biogenic species into harmful airborne pollutants.


"Isoprene - C5H8 - is released by the respiration of oak trees and is the second-most abundant naturally produced hydrocarbon (after methane) in our atmosphere," he continued.

"After a complicated series of chemical reactions, isoprene facilitates ozone production, so increased isoprene means more ozone in the air."

Ozone in the upper atmosphere blocks out harmful ultraviolet radiation from the sun, Zhang explained, but nearer the ground, it traps infrared radiation reflected back up from Earth and contributes to heating the air near the planet’s surface, the so-called "Greenhouse Effect." So, more ozone can mean rising temperatures near ground-level, contributing to global warming.

"Although near-ground ozone has some beneficial effects, providing excited oxygen atoms needed to produce the free OH radicals that help to bind other chemicals like sulfur and cleanse them from the atmosphere, excess ozone proves harmful to the health of humans and plants," Zhang said. "For example, too much ozone can retard tree growth or even kill trees. And if too many trees die, there will be more CO2 in the air, further trapping heat and raising the temperature of the planet."

Zhang and North are studying isoprene oxidation related to oak trees in the Houston area, where ozone is contributing to increasing air pollution. They are seeking to understand the critical reactions out of the 1,000 in the isoprene to ozone chain in order to find ways to abate air pollution and allow trees to continue their life-cycle without increasing environmental damage.

Zhang will be using laboratory apparatus to study isoprene using chemical ionization mass spectrometry, while North will look at the chemical process using laser-induced fluorescence. Both researchers also employ methods of quantum chemical calculation to analyze their experimental results. In addition to the NSF grant, their work is being funded by the Welch Foundation, the Texas Advanced Research Program (Chemistry) and the U.S. Department of Energy (DOE).

"The isoprene chain reaction is very complicated - in fact, it’s been studied for over 30 years without significant results with regard to fundamental details," said Zhang. "Dr. North and I seeking to discover the direction in which reaction pathways proceed. If we can fully understand the critical steps in the reaction, maybe we can determine where best to intervene in the process to keep both our oak trees and ourselves healthier."


Contact: Judith White, 979-845-4664, jw@univrel.tamu.edu; Renyi Zhang, 979-845-7656, zhang@ariel.met.tamu.edu

Judith White | EurekAlert!
Further information:
http://www.tamu.edu/

More articles from Ecology, The Environment and Conservation:

nachricht Scientists on the road to discovering impact of urban road dust
18.01.2018 | University of Alberta

nachricht Gran Chaco: Biodiversity at High Risk
17.01.2018 | Humboldt-Universität zu Berlin

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>