In nature, a forest produces about a pound of dead leaves and wood per square yard every year. This may not sound like much material, but consider the amount that would fall on an area the size of a football field or soccer field.
An American high school football field, including end zones, covers square yards by A football field-sized area in a forest would be covered by pounds, or 3. A soccer field covers square yards by 80 yards wide. An area this size in a forest would be covered by 4.
To give an idea of how much material this is, remember that an average-sized car weighs only 1. American cities produce even more organic waste garbage than forests, and very little of it decomposes and becomes recycled into new plant growth by natural processes. Every resident of Los Angeles produces 7 pounds of garbage per day! This is equal to one ton of garbage per year per person. The disposal and recycling of nutrients in garbage is a large problem because of the huge amount of garbage produced every day.
Sanitary landfills are the current solution to the garbage problem. The first modern sanitary landfill was built in Champaign, Illinois in The phrase "sanitary landfill" was invented in the s by Jean Vinenz, the commissioner of public works of Fresno, California. By , about American cities had sanitary landfills; by there were Before sanitary landfills were invented "dumps" were used to dispose of garbage. Dumps were open, the garbage was not covered, and the garbage was often burned.
Dumps smell terrible, are often surrounded by blowing paper, attract flies and provide food for large populations of rodents. Sanitary landfills have less odor, there is no black smoke from burning tires and garbage, and the number of flies and rodents is greatly reduced, hence the term "sanitary".
It opened in and covers 3, acres, a rectangular area roughly 3 by 4 miles. When it reached full capacity and closed in , its estimated height was feet. If it had been allowed to get any taller, it would have interfered with air traffic. Landfills are usually lined with several feet of dense clay and then sealed with thick layers of plastic to prevent leaks of hazardous chemicals.
The garbage is dumped in rows or piles from 10 to 20 feet high. Bulldozers are used push the garbage into rows and squash large objects. Compactors with 5 foot wide studded rollers are also used to squash the garbage. Squashed garbage takes up less space extending the life of the landfill. Each day, soil, glass, or plastic foam pellets is spread over a landfill to reduce odors and pests. The soil covering also reduces the amount of rainwater that seeps in.
Finally, the battle against microorganisms is often fought by adding chemicals known as preservatives to food. These chemicals help to inhibit the chemical reactions that allow microorganisms to break down food for energy. We hope today's Wonder of the Day didn't spoil you! Keep learning even more when you check out the following activities with a friend or family member:.
Hi matthew. Hi, anna! There are a couple of different chemical changes that can cause food to rot. The cell walls of fruits and vegetables can break down, air can cause microorganisms to land on food and break down the food, water can help microorganisms dissolve the food for energy and growth, and light and temperature can also cause chemical changes in food.
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The following is how you would cite this page:. Accessed 19 Oct. Thanks for checking this article out! Hopefully you found your answer in the article.
You should get an email alert when your comment is approved. Good question, John! We encourage you to take a little Wonder Journey to see if you can find the answer to your question. Let us know what you come up with! Thanks for asking, Iayan! Accessed 28 Feb. Great question! We believe it would just be referred to as "decomposing. That's a great question, Anonymous! Many food items have a "best by" date while others have a "sell by" date.
When foods have a "sell by" date, it doesn't necessarily mean you must eat it by that same date. It's probably good for a few more days. So, depending on the food, your dad is probably right. Hi, Marcos! We're glad you stopped by Wonderopolis to find ideas for your science project! We encourage you to check out the Try It Out activities above. Also, there are more than 1, Wonders you can explore for more ideas!
Hello, kelly! Thanks for stopping by Wonderopolis! We hope you're learning lots of new things and having lots of fun! Absolutely, Wonder Friend! We list the Wonder Sources where we find the info for the Wonders on the right hand side.
We encourage you to check those sources out, too! Thanks for asking, Brooke! The following is how you would cite the Wonder of the Day. You may use Wonderopolis as the author and since we do not list the publish date, you can use the date you accessed the article for information.
If that was today, then use today's date for your citation. Hi, jessica! Thanks for letting us know! We're sorry about that. Sometimes over time links get changed or go bad. We have updated the link to a new activity! Have fun! Hello, meredith! Great question, joy! Rotten food can really upset our stomach. It's not fun when that happens! Plus we don't want to waste food by letting it rot! There was a lot of good information in it.
Thanks for sharing your thoughts! Welcome back, Joy! You're right when you say rotten food can make your stomach hurt. Biodegradation can be thought of as waste decaying or rotting. Biodegradable matter is generally plant and animal matter and other substances originating from living organisms. Biodegradable human-made products ranging from paper bags to egg cartons. Differentiate between compostable waste and non-biodegradable waste. What foods take the longest to biodegrade?
The shortest? If organic waste is wrapped up in a plastic bag, will it degrade? Why or why not? What are these products going to turn into once they break down?
Food spoilage and deterioration is no accident. It is a naturally occurring process. To understand how to maintain the quality of food and prevent spoilage, we need to know what can cause it.
Factors that affect food spoilage include:. Many types of microorganisms can cause food problems. The microorganisms that can cause food-borne illness are called pathogenic microorganisms. Pathogenic microorganisms may grow in foods without any noticeable change in odor, appearance or taste.
Enzymes, substances naturally present in food, are responsible for the ripening process in fruits and vegetables. Enzymes are responsible for texture, color and flavor changes.
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