WHAT HAPPENS WHEN NON- BIODEGRADABLE* SUBSTANCES ENTER ECOSYSTEMS? *Substances that are broken down very slowly or not broken down at all by natural processes

They paved paradise, they put up a parking lot With a pink hotel, a boutique and a swinging hot spot Don’t it always seem to go That you don’t know what you’ve got ‘til it’s gone? They paved paradise, they put up a parking lot. They took all the trees, they put ‘em in a tree museum. They charged the people a dollar and a half just to see ‘em. Don’t it always seem to go That you don’t know what you’ve got ‘til it’s gone? They paved paradise, they put up a parking lot Hey farmer, farmer, put away your DDT I don’t care about spots on my apples but leave me the birds and the bees, Don’t it always seem to go That you don’t know what you’ve got ‘til it’s gone? They paved paradise, they put up a parking lot. Late last night, I heard the screen door slam. A big yellow taxi took away my girl man. Now don’t it always seem to go That you don’t know what you’ve got ‘til it’s gone. They paved paradise, they put up a parking lot. Originally written by Canadian Joni Mitchell, this song has been covered by Bob Dylan, Counting Crows, Amy Grant, etc. Mitchell got the inspiration for this song while vacationing in Hawaii. She was upset that such a beautiful land was being over developed. The tree museum is actually the Foster Botanical Garden in Waikiki, Hawaii. When this song was written, it did cost $1.50 to get in. It now costs $5.00. DDT is a pesticide once widely used on the Canadian prairies. It was developed in WWI to combat mosquitoes from spreading malaria to military and civilian populations. Following the publication of the book “Silent Spring” by ecologist Rachel Carson (1962), the use of DDT was banned in the USA and Canada. However, DDT is still used in many less developed parts of the world today.

DDT Dichlorodiphenyltrichloroethane Developed in WW2 to kill mosquitoes carrying malaria After the war it was used by farmers as an insecticide DDT entered lakes and rivers – Prevented fish eating birds from reproducing Banned in the 1970s – Still used in less developed countries around the world Government of Canada – DDT Video

Biological Magnification Bioaccumulation

Biological Magnification The problem occurs when a pollutant, such as DDT, PCBs (Polychlorinated biphenyls) or mercury, is present in the environment. Because they are non-biodegradable, they remain in the environment for long periods of time.

Biological Magnification Producers absorb pollutants when taking in water – Toxins are stored inside plants Herbivores eat the plants – Toxins are stored and accumulated in fat Toxins are passed along the food chain

DDT

Biological Magnification The amount of toxins increase at each trophic level Organisms that are at the top levels of the food chain are most greatly affected. Organisms who are affected the most by biomagnification are therefore 2 nd and 3 rd level consumers (including humans).

Concluding Assignment: – Choose a partner – You and your partner will be assigned an article to read and summarize. – You will be responsible for reading and summarizing the article and presenting it to the class. – You have 30 minutes! GO!