Human Impact on the environment

2

RESOURCES

RESOURCE- something used to take care of a need

TYPES:1. Non Renewable- can’t be replenished;

available only in limited amountsEx: fossil fuel coal, oil, natural

gas2. Renewable- are replaceable by

natural processes Ex: fresh water, trees

RenewableNon-

Renewable

Resources

tin Silver Phosphorus Nitrogen Air

freshwater Topsoil Oil Forests Trees

Biodiversityrefers to the variety of species in ecosystems, and the genetic variation.

• Over-hunting • Habitat loss • Invasion of non-native species

• Pollution • Climate change

Threats to Biodiversity

PollutionContamination of

soil, water, airResult of human

activityAffects organisms

and their habitats.

Ozone DepletionReduction of the ozone(O3) layer which protects the earth from UV radiation

Caused by …CFCs emitted from aerosol cans and A/Cs destroy ozone(O3)molecules

Effect- Harmful UV rays

penetrate the earth’s atmosphere

- Increase in skin cancer

Solution-don’t use aerosol cans

Global WarmingIncrease of the average temperature of the earth

Caused by … increased amounts of greenhouse gases and burning of fossil fuels

Effect - Increase in the average

temperature of EARTH

Solution - Reduce CO2 emissions - Decrease electricity

usage.

Acid RainRain containing nitric and sulfuric acid

Caused by … burning of fossil fuels releases nitrogen and sulfur compounds that combine with water and form sulfuric and nitric acid precipitation

Effect - Changes in soil chemistry

which prevent plant growth- Destruction of pond

ecosystems

Solution -burn less fossil fuels

Bio-magnificationIncreasing concentration of a harmful substance in organisms at

higher trophic levels

Caused by … non biodegradable chemicals (i.e DDT) introduced into ecosystems

Effect - Build up of non biodegradable

toxins - Increase of toxin

concentration in top predators- Possible species extinction

Solution - Use biodegradable

pesticides- The US banned the use of

DDT

Soil ErosionThe wearing away of topsoil

Caused by … wearing away of soil by water and wind; deforestation; overplowing

Effect - Loss of topsoil which is the

most fertile soil on the planet and takes a long time to recover

Solution - Contour plowing - Plant cover to

replenish nitrates in the soil

Deforestation

The destruction or loss of forests

Caused by … Overlogging

Effect - loss of trees- Loss of forest ( biodiversity

reduction- Soil erosion- Prevention of tree regrowth

due to a change in soil- Habitat fragmentation

Solution - Selective tree harvesting- Protection of old growth forests- Replant trees

Desertification

Creation of a desert with sand for soil

Caused by … Farming, overgrazing; drought

Effect - Decrease in soil, increase in

sand- Changes to ecosystems and

the species able to live in the environment

Solution - Reduce soil erosion- Don’t leave plowed fields

open without vegetation

Invasive Species

Non-native species introduced to new habitats take over and kill native organisms to the area

Caused by … importation of new species into new ecosystems

Effect - Possible destruction of

ecosystems- Inability to control the

population of non-native species

- Habitat fragmentation

Solution -import natural predators of invasive species