human impact on the environment

What is meant by “human impact on the environment”?

The ways in which human activities alter ecosystems, reduce biodiversity, and affect the balance of natural processes.

What is biodiversity?

The variety of living organisms in an ecosystem, including species diversity, genetic diversity, and ecosystem diversity.

What is pollution?

The introduction of harmful substances or energy into the environment that cause adverse effects.

Name the main types of pollution caused by humans.

• Air pollution (e.g., CO₂, SO₂, NOx, particulates)

• Water pollution (e.g., nitrates, phosphates, sewage, heavy metals)

• Soil pollution (e.g., pesticides, herbicides, heavy metals)

• Thermal pollution and noise pollution

How does air pollution affect ecosystems?

• Acid rain damages plants and aquatic habitats

• Greenhouse gases contribute to global warming

• Particulates reduce light for photosynthesis and can harm animals

How does water pollution affect ecosystems?

• Nutrient runoff causes eutrophication, leading to oxygen depletion

• Toxic chemicals harm aquatic life

• Pathogens in sewage can spread disease

How does soil pollution affect ecosystems?

• Pesticides and herbicides can kill non-target organisms

• Heavy metals accumulate in food chains (bioaccumulation)

What is deforestation?

The removal of large areas of forest for agriculture, logging, or urban development.

How does deforestation impact biodiversity?

• Loss of habitat reduces species numbers

• Fragmentation isolates populations, increasing extinction risk

• Changes microclimates and soil conditions

What is habitat destruction?

The alteration or elimination of natural habitats, making them unsuitable for the species that live there.

What is climate change?

Long-term changes in global or regional climate patterns, largely caused by increased greenhouse gas emissions.

What human activities increase greenhouse gases?

• Burning fossil fuels (coal, oil, gas)

• Deforestation reducing CO₂ absorption

• Industrial processes releasing CO₂, CH₄, N₂O

What are the effects of climate change on ecosystems?

• Shifts in species distribution

• Changes in migration and flowering times

• Coral bleaching and loss of marine biodiversity

• Increased frequency of extreme weather events

What is overexploitation?

Using natural resources faster than they can be replenished.

give examples of overexploitation

• Overfishing

• Hunting endangered species

• Excessive logging

How does overexploitation affect ecosystems?

Reduces population sizes, disrupts food chains, and can lead to extinction.

What are invasive species?

Non-native organisms introduced to an ecosystem that spread rapidly and harm native species.

How do invasive species impact ecosystems?

• Compete with native species for resources

• Prey on native species

• Introduce diseases

What is conservation?

Protecting and managing ecosystems and species to prevent biodiversity loss.

Give examples of conservation strategies.

• Establishing nature reserves and protected areas

• Captive breeding and reintroduction programs

• Habitat restoration

• Sustainable land and resource management

What is sustainable development?

Using resources in a way that meets present needs without compromising future generations’ ability to meet theirs

How can humans reduce their impact on the environment?

• Reducing carbon footprint (renewable energy, transport changes)

• Recycling and reducing waste

• Sustainable agriculture and fishing practices

• Environmental legislation and education

Why is it important to maintain biodiversity?

• Ensures ecosystem stability and resilience

• Provides food, medicine, and resources

• Supports ecological processes like pollination and nutrient cycling

How are ecosystems affected by cumulative human impacts?

They can become degraded, less productive, and may lose species permanently, reducing overall ecosystem services.