LEC 24

Question 1

Human characteristics (2)

Answer 1

1. Complex language has given the ability to communicate knowledge over time and distance
2. Knowledge give humans ability to manipulate and modify entire ecosystems

Question 2

Ecosystem (2)

Answer 2

1. Consists of ALL species interacting with each other and the physical environment around them
2. Changes to the ecosystem can have detrimental effects, on the species (including humans)

Question 3

Examples of Human Effect on Ecosystems

Answer 3

1. Cause global changes in biogeochemical cycles
   Phosphorus, nitrogen and carbon cycles are integral to living species (plants and animals)
2. Alter the climate
   High use of fossil fuels increases CO2 deposition into atmosphere (more entering than leaving) resulting in global warming and greenhouse effect
3. Affect the populations of other living species
   Land use and development leads to habitat loss, resource depletion and sometimes extinction

Question 4

Renewable Resources (4)

Answer 4

Not limited in supply

Water, solar power, plants and animals for foods can be used and will be able to replenish

Must be careful not to waste or squander them

For certain species, (ie. food sources), we need to ensure minimum population numbers are maintained

Question 5

Non-Renewable Resources (4)

Answer 5

ARE limited in supply

Once they are used, they are gone and cannot be replaced

Land, fossil fuels and minerals are all non-renewable

Efficient use can make the supply last longer, but eventually the supply runs out

Question 6

Pollution

Answer 6

Any alteration of the environment in an unwanted way

Question 7

Pollution characteristics (3)

Answer 7

1. Often caused by human activity
2. The size of the human population in an area is directly proportional to the impact on the environment
3. Global areas of large populations (LDC’s) have a more significant impact on the local resources

Question 8

Types of Pollution (7)

Answer 8

Air
Land
Water
Food
Energy
Minerals
Wastes

Question 9

eutrophication source

Answer 9

From food packaging plants, phosphates from laundry soaps

Question 10

eutrophication process (steps 1 to 3)

Answer 10

1. Increase growth rate of bacteria
2. decrease available oxygen in water
3. kills off other aquatic animals

Question 11

eutrophication results

Answer 11

Eventually leads to waterway becoming marshy and then dry land = loss of habitat