Human impacts on the environment

What is pollution?

The introduction of harmful substances into the environment

What are the main types of pollution?

Air pollution, water pollution, and land pollution

What causes air pollution?

Burning fossil fuels, industrial emissions, vehicle exhausts

What gases contribute to air pollution?

Carbon dioxide, sulfur dioxide, nitrogen oxides

What is the greenhouse effect?

The trapping of heat in the atmosphere by greenhouse gases

Which gas is the main cause of the greenhouse effect?

Carbon dioxide

What human activities increase carbon dioxide levels?

Burning fossil fuels and deforestation

What is global warming?

The increase in Earth's average temperature due to greenhouse gases

What are the effects of global warming?

Rising sea levels, climate change, extreme weather

How does deforestation contribute to global warming?

Reduces carbon dioxide absorption and increases CO₂ release

What is acid rain?

Rainwater made acidic by sulfur dioxide and nitrogen oxides

What causes acid rain?

Industrial emissions and burning fossil fuels

What are the effects of acid rain?

Damage to plants, soil, aquatic life, and buildings

What is water pollution?

Contamination of water bodies by harmful substances

What causes water pollution?

Sewage, fertilizers, pesticides, industrial waste

What is eutrophication?

The enrichment of water with nutrients leading to excessive plant growth

What causes eutrophication?

Runoff of fertilizers containing nitrates and phosphates

What happens during eutrophication?

Algae bloom, block light, plants die, decomposition increases

Why does oxygen decrease in eutrophication?

Decomposers respire and use oxygen

What is the effect of low oxygen in water?

Aquatic organisms die

What is bioaccumulation?

The build-up of toxins in an organism over time

What is biomagnification?

Increasing concentration of toxins up a food chain

Give an example of a toxic substance causing biomagnification

Pesticides like DDT

What is land pollution?

Degradation of land due to waste and chemicals

What causes land pollution?

Landfill waste, chemicals, and non-biodegradable materials

What is biodegradable waste?

Waste that can be broken down by microorganisms

Give examples of biodegradable waste

Food scraps, paper

What is non-biodegradable waste?

Waste that cannot be broken down easily

Give examples of non-biodegradable waste

Plastic, glass

Why is non-biodegradable waste harmful?

It accumulates and damages ecosystems

What is conservation?

The protection and preservation of the environment

Why is conservation important?

To maintain biodiversity and ecosystem stability

What is biodiversity?

The variety of different species in an ecosystem

What human activities reduce biodiversity?

Deforestation, pollution, overfishing, habitat destruction

What is deforestation?

The removal of forests

Why do humans carry out deforestation?

Agriculture, logging, urban development

What are the effects of deforestation?

Habitat loss, soil erosion, increased CO₂ levels

What is soil erosion?

The removal of topsoil by wind or water

Why is topsoil important?

It contains nutrients for plant growth

How does deforestation cause soil erosion?

No roots to hold soil in place

What is overfishing?

Catching fish faster than they can reproduce

What are the effects of overfishing?

Population decline and ecosystem imbalance

What is sustainable development?

Using resources to meet current needs without harming future generations

What is sustainable fishing?

Limiting catches to allow fish populations to recover

What methods help conserve fish stocks?

Fishing quotas, net size limits, closed seasons

What is captive breeding?

Breeding endangered species in controlled environments

What is reintroduction?

Returning species to their natural habitats

What are seed banks?

Storage of seeds to preserve plant species

What are zoos’ roles in conservation?

Breeding programs and education

What are national parks?

Protected areas to conserve wildlife and habitats

What is recycling?

Processing waste materials into new products

Why is recycling important?

Reduces waste and conserves resources

What is sewage treatment?

The process of removing contaminants from wastewater

How does sewage treatment reduce pollution?

Prevents harmful substances entering water bodies

What is biological control?

Using natural predators to control pests

Give an example of biological control

Ladybirds controlling aphids

What are advantages of biological control?

Reduces chemical use and pollution

What are disadvantages of biological control?

May disrupt ecosystems if not controlled

What is habitat destruction?

The loss of natural environments

What are causes of habitat destruction?

Urbanization, agriculture, mining

What is climate change?

Long-term changes in temperature and weather patterns

What causes climate change?

Increased greenhouse gases from human activity

How does climate change affect ecosystems?

Alters habitats and species survival

What is carbon footprint?

The total CO₂ emissions caused by an individual or activity

How can carbon footprint be reduced?

Using renewable energy, reducing waste, conserving energy

What are renewable energy sources?

Energy sources that do not run out

Give examples of renewable energy

Solar, wind, hydroelectric

Why are renewable energy sources important?

They reduce pollution and greenhouse gas emissions

What are non-renewable energy sources?

Energy sources that will run out

Give examples of non-renewable energy

Coal, oil, natural gas

Why should non-renewable energy use be reduced?

They cause pollution and will be depleted

What is the impact of plastic pollution?

Harms wildlife and ecosystems

How can plastic pollution be reduced?

Recycling, reducing use, reusing materials

What is ecosystem stability?

The ability of an ecosystem to maintain balance

Why does loss of biodiversity reduce stability?

Fewer species to maintain balance

What is an endangered species?

A species at risk of extinction

What is extinction?

The permanent loss of a species

What are causes of extinction?

Habitat loss, climate change, overexploitation

What is overexploitation?

Using resources faster than they can be replaced