Science 10 Ecosystem processes and relationships

 By the end of this seminar and related readings, you should be able to : ◦ Locate the Peace River area’s biome and ecozone. ◦ Understand food relationships, nutrient cycles and bioaccumulation processes. ◦ Recognize some plants, animals, fish, birds, amphibians, and reptiles that inhabit the Peace River Valley. ◦ Explore relationships between living elements of the Peace River Valley. ◦ Demonstrate comprehension of processes with applied examples from the Peace River Valley. ◦ Propose a bioaccumulation scenario using knowledge of cycles and local species.

Where are we?

Try to identify all the plants, animals, birds, fish, amphibians and reptiles on your cards. All of these species are found in the Peace River Valley. Write the correct species names on the cards.

Theory

What can you see in this picture?

Theory

Practice! On your handouts Food Chain Food Pyramid Food Web Nutrient Cycle

Theory

 refers to the gradual buildup of chemicals in living organisms. ◦ Many harmful chemicals cannot be decomposed naturally. ◦ These chemicals can be eaten or absorbed and sometimes cannot be removed from the body of the organism effectively.

 is the process by which chemicals become more concentrated at each trophic level. ◦ At each level of the food pyramid, chemicals that do not get broken down build up in organisms. ◦ When a consumer in the next trophic level eats organisms with a chemical accumulation, it receives a huge dose of the chemical(s).

 Enters ecosystems through the burning of fossil fuels, waste incineration, mining, and manufacturing (ie: batteries)  Mercury bioaccumulates in the brain, heart and kidneys of many animals and fish.  Elevated mercury levels in fish tissue is a common side-effect of flooding to create hydroelectric dam reservoirs. (Stokes & Wren, 1987)

Practice! On your handouts Which species would be effected by increased mercury levels in the Peace River, due to an additional hydroelectric dam?

 What biotic elements would be affected by increased mercury levels in the Peace river?  What trophic levels would be most impacted by mercury contamination of the Peace River?  What are the possible impacts of your scenario, on the natural ecosystem, and on humans that interact with it?

If you were interested in our topics today, you can learn more by reading  Bioaccumulation of Mercury by Aquatic Biota in Hydroelectric Reservoirs  The Living Peace River Valley Both are found on