Lecture 3: impact of humanity on environment

Question 1

Environment

Answer 1

The physical and biological habitat that surrounds us.

Question 2

Pollution

Answer 2

The undesired change in the physical, chemical, or biological characteristics of the air, water, or land that can harmfully affect the health, survival, or activities of humans or living organisms

Question 3

Atmosphere

Answer 3

Outer layer of gases extending from the surface of the Earth into space

Question 4

Hydrosphere

Answer 4

Bodies of water such as oceans, lakes, and streams (includes shallow groundwater bodies that interflow with surface water, i.e. water underground)

Question 5

Lithosphere

Answer 5

Outer mantle and crust of the Earth that provides physical support to our environment

Question 6

Biosphere

Answer 6

Traverses all three - atmosphere, hydrosphere, lithosphere.
Layer in which life exists traversing the atmosphere, hydrosphere, and lithosphere.
Waste is generated, received and assimilated
Perturbations to the environmental equilibrium will induce a natural restorative response (dilution, chemical degradation, biological conversion)
The more severe the perturbation, the more time is required for natural restoration to take place

Question 7

What does severity of environmental impact depend on?

Answer 7

Total population, density, the draw on resources, and removal/treatment of waste

Question 8

Impact of deforestation

Answer 8

Deforestation can lead to soil erosion, and encroaching deserts

Question 9

Impact of increased urbanization and industrialization?

Answer 9

produces high concentrations of waste.

Question 10

Impact on three layer by waste production:
Solid waste

Answer 10

generated affects the lithosphere and the hydrosphere (leaching into grounwater)

Question 11

Impact on three layer by waste production:
Burning of fuels

Answer 11

generates airborne particulate emissions that affect atmosphere (smog), lithosphere (dust), and hydrosphere (acid rain).

Question 12

Impact on three layer by waste production:
Waste water

Answer 12

generated affect hydrosphere and lithosphere ( via deposits).

Question 13

How do we prevent pollution from reaching hydrosphere?

Answer 13

Regulation: capping levels or banning of pollutants (proactive, preventative method)

Treatment: removing pollutants from wastewater prior to reintroduction

Question 14

Two major means for pollution to enter into the hydrosphere

Answer 14

Surface water: waste water, direct introduction of pollution
Groundwater: leaching of contaminants into the ground (e.g. salts, heavy metals, synthetic organics)

Question 15

Water Treatment> Physical processes>screening

Answer 15

Remove large suspended solids and particulates
Clarify suspensions and concentrates solids.
ex. crocodile

Question 16

Water Treatment> Physical processes>settling

Answer 16

remove finer suspended particles from water.
gravity causes the heavier particles to settle to the bottom of the basin.

Question 17

Water Treatment> Biological processes>

Answer 17

Aerobic (oxygen) and anaerobic (without oxygen), so oxygenated/non-oxygenated processes
Eliminate organics using microbes (mainly bacteria)
Convert organics into CO2, H20, CH4, etc.
ex. sugar

Question 18

Water Treatment> Chemical processes>disinfection

Answer 18

helps prevent waterborne diseases.
addition of chemicals or physical agents that are effective in killing or inactivating microorganisms

Question 19

Water Treatment> Chemical processes>precipitation

Answer 19

remove dissolved substances from water.
changing the solubility of certain substances in water. When the solubility limit is exceeded due to the addition of a precipitant, solid particles are formed and can be separated from the water