Topic 4

Question 1

Water statistics

Answer 1

97% in oceans, 2.6% freshwater

Question 2

Human impacts on the water cycle

Answer 2

Withdrawals (domestic, irrigation, agriculture, industry)

Discharges (adding pollution)

Changing the speed/direction of the water flow

Question 3

Oceans and energy distribution

Answer 3

Important in distribution of global energy

Question 4

Water scarcity

Answer 4

How much we use, how it’s used, little to no access

Question 5

Things that impact water

Answer 5

Climate changes impacts rainfall
Aquifers are being exhausted
Freshwater can become contaminated
Irrigation leads to salinization
Pollution
Warm water released w less DO

Question 6

Solutions

Answer 6

Increase freshwater supplies
Reduce domestic usage
Use carwashes
Grey water systems
Reduce pesticides and fertilizer use
Replace chemicals with organics

Question 7

Marine ecosystem and food webs are

Answer 7

High biodiversity

Higher productivity

Question 8

Phytoplankton

Answer 8

Can do photosynthesis, 99% of productivity in oceans

Question 9

Zooplankton

Answer 9

Animals, eat phyto and their waste

Question 10

Benthic

Answer 10

Lives on sea bed

Question 11

Pelagic

Answer 11

Lives suspended in the water

Question 12

Fisheries

Answer 12

Shellfish and vertebrates
Important food source for humans
70% are exploited
Demand is rising w better technology but fish aren’t there

Question 13

Aquaculture impacts

Answer 13

Loss of habitat
Pollution
Spread of disease
Escape of GM species
Escape may outcompete native species

Question 14

Why is the wild fishing industry unsustainable?

Answer 14

Advanced technology
Large fleets (can keep taking more and more)

Question 15

Maximum sustainable yield

Answer 15

Highest amount that can be taken without permanently depleting the stock

SY=total energy or biomass at time plus one - total energy and biomass at time two

SY= annual growth and recruitment-annual death and emigration

Question 16

Cons to using MSY

Answer 16

Populations predicted, not counted 
Impossible to be precise about pop size
Estimates are made on past years
Model doesn't allow for sex or age dynamics
Disease may strike a population

Question 17

Freshwater pollutant sources

Answer 17

Agriculture, sewage, industrial discharge, solid domestic waste

Question 18

Marine pollutant sources

Answer 18

Rivers, pipelines, atmosphere, human activities at sea

Question 19

Biochemical oxygen demand(BOD)

Answer 19

Measurement of DO required to break down organic material

Question 20

Biotic index

Answer 20

Indirectly measures pollution by looking at the species in the community and their tolerances, diversity, and abundance

Question 21

Direct measurements of water pollution

Answer 21

Salt water: salinity pH temp

Freshwater: pH temp DO

Question 22

Altering human activity

Answer 22

Ban or limit detergents
Buffer zones
Detergents w/o phosphates

Question 23

Regulating and reducing

Answer 23

Treat wastewater before release (remove phosphates and nitrates)
Divert or treat sewage waste effectively
Minimize fertilizer usage on agricultural lands

Question 24

Restoration

Answer 24

Pump air thru lakes
Remove excess weeds
Restock water w appropriate organisms

Question 25

Why food supply is short in some countries

Answer 25

Conflict/war

Lack of storage in LEDCs

Question 26

Process that reduce sun hitting earths surface

Answer 26

Absorption, reflecting, scattering