How Much Oxygen Does One Tree Produce?

You've probably heard that trees produce oxygen, but have you ever wondered just how much oxygen one tree makes? The amount of oxygen produced by a tree depends on several factors, but here are some typical calculations.
 
The atmosphere of the Earth has a different composition from that of other planets in part due to the biochemical reactions of Earth's organisms. Trees and plankton play a big role in this. You've probably heard that trees produce oxygen, but have you ever wondered how much oxygen that is? You'll hear a range of numbers and ways of presenting them because the amount of oxygen produced by a tree depends on the species of tree, its age, its health, and also on the tree's surroundings. According to the Arbor Day Foundation, "a mature leafy tree produces as much oxygen in a season as 10 people inhale in a year." Here are some other quoted figures regarding the amount of oxygen produced by a tree:

"A single mature tree can absorb carbon dioxide at a rate of 48 lbs./year and release enough oxygen back into the atmosphere to support 2 human beings."
- McAliney, Mike. Arguments for Land Conservation: Documentation and Information Sources for Land Resources Protection, Trust for Public Land, Sacramento, CA, December, 1993

"One acre of trees annually consumes the amount of carbon dioxide equivalent to that produced by driving an average car for 26,000 miles. That same acre of trees also produces enough oxygen for 18 people to breathe for a year."
- New York Times
“A 100-ft tree, 18" diameter at its base, produces 6,000 pounds of oxygen."

"On average, one tree produces nearly 260 pounds of oxygen each year. Two mature trees can provide enough oxygen for a family of four."
- Environment Canada, Canada's national environmental agency

"Mean net annual oxygen production (after accounting for decomposition) per hectare of trees (100% tree canopy) offsets oxygen consumption of 19 people per year (eight people per acre of tree cover), but ranges from nine people per hectare of canopy cover (four people/ac cover) in Minneapolis, Minnesota, to 28 people/ha cover (12 people/ac cover) in Calgary, Alberta."
- U.S. Forest Service and International Society of Arboriculture joint publication

The water you're drinking; is it really safe?

To be specific, the TAP water your drinking; safe or not? while it typically is safe here and now in Canada, there was a time in a farming town in western Ontario called Walkerton where the water was contaminated by a strain of  O157:H7 E. Coli Bacteria in may 2000. the E. Coli comes from the intestines of healthy cattle and can result in permanent kidney damage or be fatal to humans if they eat it in undercooked hamburger, unpasteurized milk or contaminated water. At least seven people died directly from drinking the E. coli contaminated water, and about 2,500 became ill. Investigators suspect run-off from cattle manure as a probable source of the E. coli in the water. This hasn't been the only case of poor water testing in Canada; In the spring of 1996, hundreds of people in Collingwood, (an hour's drive from Walkerton) become ill after Cryptosporidium, a parasite linked to animal feces, contaminated the drinking water. In 2001 a similar outbreak in North Battleford, Saskatchewan caused by Cryptosporidium affected at least 5,800 people. while no one dies in both of these cases, it is another highlight on Ontario's poor water testing and regulations then. Now of course, with the affect that it had on the people of Walkerton and elsewhere, the government has since tightened up, including enacting the clean water act of 2006, which protects existing and future sources of drinking water. so with that please don't be considering stocking up on crates of bottled water, that is a whole other story of its negative effects on the environment and our bodies. Our water now is relatively safe if you ignore the fluoride which can cause toxicological side-effects so just remember how people just couldn't be sure 12 years ago in the small town of Walkerton, Ontario the next time you're getting water from the tap.

Do you believe the Walkerton tragedy could have been prevented? if so, what are the steps you think could have been taken to prevent this tragedy from happening?

Read here for more details:
* http://www.thecanadianencyclopedia.com/articles/macleans/walkerton-tragedy
*http://www.cbc.ca/news/canada/story/2010/05/10/f-walkerton-water-ecoli.html

Nitrogen Dioxide, Ozone & Lead Partner to Increase Pollution Dangers to Urban Children

I thought that this article may be an interesting one to post since it related to things that we have been discussing in class. I thought that problems with lead paint only pertained to the past, but I guess I was wrong!




The adverse health effects of ozone (O₃) and nitrogen dioxide (NO₂) have been known for decades. The Clean Air Act was established in 1963, but ambient a quality was not regulated until 1970, and by 1971 EPA had established one hour National Ambient Air Quality Standard (NAAQS) of 0.08 ppm for both O₃ and nitrogen dioxide. Nitrogen dioxide and ozone are two of the major outdoor ambient chemical pollutants affecting asthmatics. In addition, nitrogen dioxide plays a role in formation of acid rain, contributes to global warming, and hampers the growth of plants. Ground-level ozone interferes with a plant's ability to manufacture (photosynthesize) and store food, and lowers plant resistance to disease.

Just when we think that we are getting a handle on the entire criminal record of these two compounds, scientists from the University of California, Irvine have linked them to another environmental and health outlaw, lead (Pb). In an abstract published in Environ. Sci. Technology, October 14, 2009 (article ASAP) R. D. Edwards, N. L. Lam, L. Zhang, M. A. Johnson and M. T. Kleinman from the School of Medicine, University of California, Irvine reported that nitrogen dioxide (NO₂) and ozone (O₃) from vehicles emissions react with surfaces painted with lead based paint and increase the release of lead. According to Edwards, paint is made of two basic components: pigment granules and an unsaturated polymeric binder that holds them together. O₃ and NO₂typically react with unsaturated compounds. Edwards and colleagues suspected that this characteristic might make lead pigment granules become deposited in house dust or be more available to children's hands in urban environments where O₃ and NO₂ are frequently in high concentration.

The researchers coated stainless steel with a thin layer of lead based paint and exposed them to NO₂ and O₃. They then evaluated the coated surfaces using reflectometry and scanning electron microscopy. They also wiped the surfaces and calculated the amount of lead on the wipes. Edwards and his colleagues reported that NO₂ and O₃ changed the surfaces' morphology and significantly increased the amount of lead that can were wiped off them.

The results of this research suggests that a lot more emphasis must be placed on eliminating lead based paint from the urban environment and lowering the emission of O₃ and NO₂ in American cities that are still remediating old buildings and in developing nations where lead based paint is still being sold.

Roberta Barbalace. Nitrogen Dioxide, Ozone & Lead Partner to Increase Pollution Dangers to Urban Children. EnvironmentalChemistry.com. Dec. 3, 2009. Accessed on-line: 1/15/2012
http://EnvironmentalChemistry.com/yogi/environmental/200912_nitrogen_dioxide_ozone_and_lead_endanger_children.html
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The Clean Air Act

You've probably heard about the Clean Air Acts and can figure out they have something to do with air pollution, but what else do you know about Clean Air Act legislation? Here's a look at the Clean Air Acts and answers to some common questions about them.

The Clean Air Act is the name of any of several pieces of legislation aimed at reducing smog and other types of air pollution.

In the United States, the Clean Air Acts include the Air Pollution Control Act of 1955, Clean Air Act of 1963, Air Quality Act of 1967, the Clean Air Act Extension of 1970, and Clean Air Act Amendments in 1977 and 1990. State and local governments have passed supplemental legislation to fill in gaps left by the federal mandates. The Clean Air Acts have addressed acid rain, ozone depletion, and the emission of atmospheric toxins. The laws have included provisions for emissions trading and a national permits program. The amendments established requirements for gasoline reformulation.
In Canada, there have been two acts with the name "Clean Air Act". The Clean Air Act of the 1970s regulated the atmospheric release of asbestos, lead, mercury, and vinyl chloride. This Act was replaced by the Canadian Environmental Protection Act in the year 2000. The second Clean Air Act (2006) was directed against smog and greenhouse gas emissions.

In the United Kingdom, the Clean Air Act of 1956 legislated zones for smokeless fuels and relocated power stations to rural areas. The Clean Air Act of 1968 introduced tall chimneys to disperse air pollution from the burning of fossil fuels.

Impact of the Clean Air Acts
The legislation has led to the development of better pollution dispersion models. Critics say the Clean Air Acts have cut into corporate profits and have led companies to relocate, while proponents say the Acts have improved air quality, which has improved human and environmental health, and have created more jobs than they have eliminated.