Human Impact Questions
Water
Why is water important?
Water is an essential need for human survival. We have about 97% of
Earth’s water is salty, which leaves us with only 3% fresh water.
How can humans pollute or threaten water quality and explain each
way?
Water is polluted by several ways:
1. Thermal pollution which is the heating of natural water due to
human activity, such as nuclear power plants when they return
water back to the lake or river
2. Chemical pollution is when harmful pollutants are added to water
source. Agricultural industry might put pesticides, herbicides, and
fertilizer on their crops and in return the run off pours into our
rivers, lakes and can get into our aquifers. Acid rain is another
chemical pollutant that is formed when fossil fuels mix with water
in the air. Increase in ph of soil and water can harm plants and
animals.
3. Biological pollution occurs when live or dead organism’s are
added to water supplies. Example is when wastewater
contaminates water source.
4. Eutrophication is when there is an increase of nutrients in the
water which can cause an overgrowth of algae. This may be a
result of human wastewater and fertilizer runoff into water
source which will change the natural composition of water
How can urbanization affect the water quality and demand?
The greater demand for fresh water in cities is threatening the
availability of water for many people. Even though water is considered
renewable resource, it can become nonrenewable if we use it faster
than it is created. Sometimes dams and irrigations canals are created
to change the natural flow of water and because of this the local
ecology can change to which can hurt the habitat. Overuse of water
can cause streams, rivers, and lakes to dry up. Aquifers can dry up or
salt water intrusion can occur from changing the natural flow of water
Air
Why is air important?
Air is important for human survival for the need to breathe. In
addition, our atmosphere protects us from harmful electromagnetic
waves, such as UV light from entering our atmosphere. In addition, the
atmosphere keeps the earth warm enough for our survival.
What kind of primary pollutants are commonly found in air?
Carbon monoxide, sulfur dioxide, and ground level ozone. Particulates
are tiny solid particles found in our atmosphere which can come from
vehicle exhaust.
How does urbanization affect the atmosphere?
Increase in population means and increase in burning of fossil fuels
which release greenhouse gases into our atmosphere which eventually
will cause an increase in earth’s temperature causing our polar ice caps
to melt. In addition, the increase of air pollution is causing
chlorofluorocarbons to cause the ozone layer to thin out, which
increase harmful radiation entering our atmosphere.
What pollutants come from gas exhaust?
Smog. Also, when vehcle exhaust interacts with water in the
atmosphere it will form acid rain.
How might human activity cause acid rain?
Fossil fuels burn sulfur dioxide and nitrogen oxide into the air and when
these gases mix water in the atmosphere they form sulfuric acid and
nitric acid. These are very strong acids and they are harmful to the
environment..
The acid rain gets into the soil and water and increases the acidic level
of these substances. This in turn will cause organisms to be killed off
that live in water and soil.
How does human activity change earth’s climate?
With the burining of fossil fuels this is causing the thinning of our
atmosphere. Which will then cause our global temps to increase and
over time they have risen. With the increase in temps, this is causing
our polar ice caps to melt at a faster rate, changes in rainfall patterns
causing more severe storms.
How does air pollution affect ozone layer?
The chemicals called chlorofuorocarbons (CFCs) are causing the ozone
to thin out by breaking the oxygen down. Our ozone layer protects our
earth from harmful radiation and blankets our earth to maintain safe
temps.
Land
Why is soil important?
Soil provides habitat for organisims, agriculture for crops, and stores
water and nutrients.
Why is land important?
Land is important for recreational purposes, transportation, agriculture,
residential, commercial and industrial use.
What is land degradation?
Is the process which human activity and natural process damage land to
the point that it can no longer support the local ecosystem.
What are three human practices that affect land degradation?
Desertification, deforestation, and poor farming practices
What is urban sprawl (urbanization) and how might it affect land use?
Urban sprawl is also known as urbanization. This is when forests, fields,
and grass land is replaced with houses, roads, schools, commercial
buildings, and shopping areas..
Urban sprawl decreases the amount of farmland that can be used for
crops, natural areas for habitats for organisms, increases amount of
asphalt (roads) and concrete.
Increase of concrete and asphalt causes runoff to be sent to storm
drains instead of going into the ground and aquifers. Runoff then can
lead to increase in erosion.
How might erosion speed up the process of land degradation?
Since trees and plants might have been removed by deforestation, the
roots of these plants and trees help keep soil intact. When land is
cleared the soil is no longer protected which can cause erosion.
What is desertification and what causes it?
Is the process by which land becomes more desert like and unable to
support life. Deforestation and urbanization cause desertification
How can humans repair land degradation?
Replace plants and trees by preservation, reforestation, and
reclamation Reducing urban sprawl, incorporate soil conservation by
terracing crops, counter plowing, and strip cropping
How does urbanization cause deforestation?
When forests are replaced with buildings, deforestation can lead
towards soil erosion. Rainwater runoff from urban areas can increase
erosion of nearby soils. With increase in population then there is
increase in crops. Farmers can incorporate poor farming practices
which can deplete the nutrients from soil.
Deforestation increases erosion, why?
Rainwater runoff from urban areas can increase erosion of nearby soils.
The roots of trees and plants are removed which makes the soil weak
and due to weathering it can cause the soil to erode away.
What is deforestation?
The removal of trees and other vegetation from areas of forests.
Surface mining causes deforestation by removing vegetation and soil to
get to the minerals that are below the surface.