Unit E Lesson E11
Completion requirements
Lesson E11: Water Quality Affects Living Things
Video Lesson
How do dissolved substances in water affect both aquatic and non-aquatic organisms? Watch this video to learn more about how water quality affects living things.
Lesson E11: Water Quality Affects Living Things
Figure E.3.11.1 – Acid rain kills trees.
Figure E.3.11.2 – Acid rain is caused by factory and power plant gas emissions.
Figure E.3.11.3 – Acidic water causes fish to die.
Reading
and Materials for This Lesson
Science in Action 8
Reading: Pages 386–389
Materials:
2 clear plastic cups or jars (the same size), white sand, water, food colouring, measuring cups, modelling clay.
Acid Rain
Coal-burning power stations and factories release waste gases into the air through smokestacks. When some of these gases dissolve in atmospheric water droplets, they create acids. When acidic water droplets form large clouds, acid rain falls. Because clouds move, acid rain often falls in areas far from the industrial source.
Low pH acid rain has negative effects on both aquatic and non-aquatic ecosystems. Acid rain increases the acidity of rivers and lakes. Fish and other organisms are very sensitive to acidic conditions. For example, adult fish die and fish eggs don’t hatch in acidic water. Acid rain affects nutrients in soil, which can harm and eventually kill trees and plants.
Coal-burning power stations and factories release waste gases into the air through smokestacks. When some of these gases dissolve in atmospheric water droplets, they create acids. When acidic water droplets form large clouds, acid rain falls. Because clouds move, acid rain often falls in areas far from the industrial source.
Low pH acid rain has negative effects on both aquatic and non-aquatic ecosystems. Acid rain increases the acidity of rivers and lakes. Fish and other organisms are very sensitive to acidic conditions. For example, adult fish die and fish eggs don’t hatch in acidic water. Acid rain affects nutrients in soil, which can harm and eventually kill trees and plants.
Watch More
Whatever Happened to Acid Rain?
Watch this video to learn about acid rain and its effects on living things.
Watch this video to learn about acid rain and its effects on living things.
Figure E.3.11.4 – Groundwater can become contaminated with surface pollutants.
Figure E.3.11.5 – Clay and plastic lines new landfills.
Figure E.3.11.6 – E. coli bacteria are just one pollutant that can enter the groundwater by leaching.
Groundwater Contamination
Human health can be affected negatively if surface pollutants contaminate groundwater. This can occur when rain and snow water dissolve surface substances. Leaching occurs when the water and dissolved substances travel downward through soil and rock. Fertilizer and pesticides are examples of substances that can leach from farm fields into groundwater. Hazardous waste can leach from landfills into groundwater, which is why modern landfills are lined with clay and a plastic sheet.
Harmful bacteria and viruses can also contaminate groundwater. For example, in 2000, groundwater contamination happened in the town of Walkerton, Ontario. E. coli bacteria from farm field manure washed into a well near the town. The bacteria multiplied and spread in the groundwater. Before the water was tested, 2300 town residents became sick, and 7 people died.
Human health can be affected negatively if surface pollutants contaminate groundwater. This can occur when rain and snow water dissolve surface substances. Leaching occurs when the water and dissolved substances travel downward through soil and rock. Fertilizer and pesticides are examples of substances that can leach from farm fields into groundwater. Hazardous waste can leach from landfills into groundwater, which is why modern landfills are lined with clay and a plastic sheet.
Harmful bacteria and viruses can also contaminate groundwater. For example, in 2000, groundwater contamination happened in the town of Walkerton, Ontario. E. coli bacteria from farm field manure washed into a well near the town. The bacteria multiplied and spread in the groundwater. Before the water was tested, 2300 town residents became sick, and 7 people died.
Try It!
Leaching
Try this experiment to observe how substances leach through the ground.
Materials:
Try this experiment to observe how substances leach through the ground.
Materials:
- 2 clear plastic cups or jars (the same size)
- White sand
- Water
- Food colouring
- Measuring cups
- Modelling clay
Instructions:
- Fill one plastic cup completely with sand.
- Fill one plastic cup halfway with sand. Completely cover the sand with a 1 cm layer of modelling clay. Fill the remainder of the plastic cup with sand.
- Add 10 drops of food colouring to the sand surface in both cups.
- Watch the plastic cups for 3 minutes. What do you observe?
- Carefully pour 50 ml (ÂĽ cup) of water onto the sand surface in both cups.
- Watch the plastic cups for 3 minutes. What do you observe?
Questions:
Think about the following questions very carefully. Then, type or write your answers. After you have your answers, click the questions for feedback.
Think about the following questions very carefully. Then, type or write your answers. After you have your answers, click the questions for feedback.
In this experiment, without water, the food colouring stayed near the sand surface. The added water dissolved the food colouring and helped it travel downwards through the sand. In a similar way, rainwater dissolves surface pollutants and helps
them travel downwards through soil.
The modelling clay blocked the food colouring and water from travelling further downward. Landfills are lined with clay to block harmful pollutants from travelling down through soil and rock to groundwater.
Connections
Figure E.3.11.7 – Tailings ponds are located near northern Alberta’s oil sands.
Figure E.3.11.8 – Tailings ponds store wastes created during oil sands production.
Connections – Environment
>> Tailings Ponds
Tailings ponds are a byproduct of metal and oil sands mining. Water and leftover substances from the mining separation process are stored in tailings ponds.
After oil sands are dug from the ground, they are mixed with hot water and chemicals called diluent. This separates the useful oil bitumen from the sand. Leftover sand, water, diluent, and bitumen are pumped into a tailings pond. Sand settles to the bottom of the tailings pond, while the water is recycled in oil sands separation. The leftover crude oil bitumen and diluent float on the top of the tailings pond.
The metal mining industry also creates tailings ponds. Mined rock is ground up into tiny particles and combined with water to separate desired metals like gold and copper. Leftover waste water, unwanted metallic minerals, and extraction chemicals are stored in a tailings pond. In 2014, a mining tailings pond in British Columbia leaked hazardous mining waste into nearby lakes and rivers.
Tailings ponds are an environmental concern because they contain harmful chemicals. Tailings ponds are not tightly sealed from the underlying soil, so harmful chemicals can potentially leach into surrounding rock and groundwater. If waterfowl birds like ducks land on an oil sands tailings pond, their feathers become coated with toxic oil. Oil companies have installed noise cannons and scarecrows on tailings ponds to scare away birds, but these strategies are not always successful.
>> Tailings Ponds
Tailings ponds are a byproduct of metal and oil sands mining. Water and leftover substances from the mining separation process are stored in tailings ponds.
After oil sands are dug from the ground, they are mixed with hot water and chemicals called diluent. This separates the useful oil bitumen from the sand. Leftover sand, water, diluent, and bitumen are pumped into a tailings pond. Sand settles to the bottom of the tailings pond, while the water is recycled in oil sands separation. The leftover crude oil bitumen and diluent float on the top of the tailings pond.
The metal mining industry also creates tailings ponds. Mined rock is ground up into tiny particles and combined with water to separate desired metals like gold and copper. Leftover waste water, unwanted metallic minerals, and extraction chemicals are stored in a tailings pond. In 2014, a mining tailings pond in British Columbia leaked hazardous mining waste into nearby lakes and rivers.
Tailings ponds are an environmental concern because they contain harmful chemicals. Tailings ponds are not tightly sealed from the underlying soil, so harmful chemicals can potentially leach into surrounding rock and groundwater. If waterfowl birds like ducks land on an oil sands tailings pond, their feathers become coated with toxic oil. Oil companies have installed noise cannons and scarecrows on tailings ponds to scare away birds, but these strategies are not always successful.
Figure A.2.3.9 – Bitumen is separated from sand in tailing ponds like the one shown here.
Figure A.2.3.10 – The mining of minerals, like uranium, also requires the use of tailings ponds.
Watch More
Environmental Concerns – Tailings Ponds
Watch this video to learn more about the environmental problem of tailings ponds.
Watch this video to learn more about the environmental problem of tailings ponds.
This news report explains the 2014 Mount Polley tailings pond disaster.
Lesson Activity
Figure A.2.3.11 – Some fish farms are located in the ocean.
Figure A.2.3.12 – Fish farms raise lots of fish in a small volume.
Problem:
As wild ocean fish populations in the ocean decrease, people are turning to fish farming instead of open sea fishing, to obtain fish for human consumption.
Some fish farms raise fish in enclosed cages in the ocean. This is a controversial practice because some people are concerned about how fish farming affects water quality for wild fish species.
In this activity, you will learn more about the controversy over fish farming. You will collect information on both sides of the issue.
Some fish farms raise fish in enclosed cages in the ocean. This is a controversial practice because some people are concerned about how fish farming affects water quality for wild fish species.
In this activity, you will learn more about the controversy over fish farming. You will collect information on both sides of the issue.
Download
DOWNLOAD this document. It provides a space for you to record your advantages
and disadvantages of fish farming.
Instructions:
- Construct a table with two columns. You can do this on a sheet of paper or type it.
- Title the columns “Advantages of Fish Farming” and “Disadvantages of Fish Farming”.
- Watch these videos. As you watch the videos, listen for examples of advantages and disadvantages to fish farming. Pause the video when you hear an example and summarize the example in the correct column of your table.
Video Research:
This video explains the development of fish farming and recent innovations to fix its disadvantages.
Watch this video to learn more about some advantages of fish farming.
This video shows the world’s largest fish farm in the open ocean.
This video explains some of the risks and rewards of salmon farming.
This video explores the controversy about farming salmon in natural salmon habitat.
Fish farming can even be found on the prairies.
Sharing:
Congratulations on completing this activity! The subject of fish farming is interesting – consider sharing your list of advantages and disadvantages with your teacher and fellow students in the course Sharing Forum. You can also put your opinion in your post if you like – are you for or against fish farming?
Congratulations on completing this activity! The subject of fish farming is interesting – consider sharing your list of advantages and disadvantages with your teacher and fellow students in the course Sharing Forum. You can also put your opinion in your post if you like – are you for or against fish farming?
Make sure you have understood everything in this lesson. Use the Self-Check below, and the Self-Check & Lesson Review Tips to guide your learning.
Unit E Lesson 11 Self-Check
Instructions
Complete the following 6 steps.
Don't skip steps – if you do them in order, you will confirm your
understanding of this lesson and create a study bank for the future.
- DOWNLOAD the self-check quiz by clicking here.
- ANSWER all the questions on the downloaded quiz in the spaces provided. Think carefully before typing your answers. Review this lesson if you need to. Save your quiz when you are done.
- COMPARE your answers with the suggested "Self-Check Quiz Answers" below. WAIT! You didn't skip step 2, did you? It's very important to carefully write out your own answers before checking the suggested answers.
-
REVISE your quiz answers if you need to. If you answered all the questions correctly, you can skip this step. Revise means to change, fix, and add extra notes if you need to. This quiz is NOT FOR MARKS, so it is perfectly OK to correct
any mistakes you made. This will make your self-check quiz an excellent study tool you can use later.
- SAVE your quiz to a folder on your computer, or to your Private Files. That way you will know where it is for later studying.
- CHECK with your teacher if you need to. If after completing all these steps you are still not sure about the questions or your answers, you should ask for more feedback from your teacher. To do this, post in the Course Questions Forum, or send your teacher an email. In either case, attach your completed quiz and ask; "Can you look at this quiz and give me some feedback please?" They will be happy to help you!
Be a Self-Check
Superhero!
Self-Check Quiz Answers
Click each of the suggested answers below, and carefully compare your answers to the suggested answers.
If you have not done the quiz yet – STOP – and go back to step 1 above. Do not look at the answers without first trying the questions.
You would expect to see a lower number and diversity of species. Most aquatic species don’t thrive well in acidic conditions. With less available dissolved oxygen, species such as fish start to die.
The wetland has a good water quality because a diversity of species are found in the area. Ecosystems with poor water quality cannot support a wide variety of species.
Even though the river contains a variety of species, you should not drink the water. The river water still might contain invisible microorganisms that harm humans but not other species.
The slimy green scum is green algae. When green algae grows quickly and dies, bacteria that decompose the algae use up all the oxygen in the water, not leaving enough oxygen for fish. You would expect to see low oxygen levels in this river.
You would also expect to find a low number of fish in this river.
The water quality in the lake improved over five years. The level of dissolved oxygen increased, the water became less acidic, and the amount of algae in the lake decreased. These changes all indicate improved water quality for a variety of
species.