Question 1:
State three human activities that have negative impacts on the environment.
Answer:
Deforestation, open burning, animal farming, mining, agriculture and combustion (Any three activities)
State three human activities that have negative impacts on the environment.
Answer:
Deforestation, open burning, animal farming, mining, agriculture and combustion (Any three activities)
Question 2:
Explain how an agricultural activity can cause the death of aquatic animals.
Answer:
The usage of nitrate and phosphate fertilisers causes eutrophication. Algae grow rapidly until they cover up the surface of water. The photosynthesis rate in water becomes low. The content of dissolved oxygen in the water is reduced. Aquatic plants will be deprived of oxygen and finally dies.
Explain how an agricultural activity can cause the death of aquatic animals.
Answer:
The usage of nitrate and phosphate fertilisers causes eutrophication. Algae grow rapidly until they cover up the surface of water. The photosynthesis rate in water becomes low. The content of dissolved oxygen in the water is reduced. Aquatic plants will be deprived of oxygen and finally dies.
Question 3:
How does an increase in the concentration of greenhouse gases contribute to the rise in the temperature of the earth?
Answer:
Increase in human activities such as burning of fossil fuels increases the release of greenhouse gases such as carbon dioxide gas. This gas traps heat in the atmosphere, causes an increase in the Earth’s temperature.
How does an increase in the concentration of greenhouse gases contribute to the rise in the temperature of the earth?
Answer:
Increase in human activities such as burning of fossil fuels increases the release of greenhouse gases such as carbon dioxide gas. This gas traps heat in the atmosphere, causes an increase in the Earth’s temperature.
Question 4:
Justify the importance of maintaining rivers as a habitat in an ecosystem.
Answer:
With the presence of habitats, aquatic animals are able to reproduce. Aquatic animals such as fish and shrimps are the sources of protein. Rivers can provide working opportunity to the fishermen to increase their source of income.
Justify the importance of maintaining rivers as a habitat in an ecosystem.
Answer:
With the presence of habitats, aquatic animals are able to reproduce. Aquatic animals such as fish and shrimps are the sources of protein. Rivers can provide working opportunity to the fishermen to increase their source of income.