Freshwater pollution

Question 1

What is fresh water?

Answer 1

any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total solids

Question 2

Salinity of fresh water?

Answer 2

<0.05% and 0.5 ppt

1ppt = 1000mg/L

Question 3

what is the salinity that freshwater organisms can tolerate?

Answer 3

<1 ppt

1ppt = 1000 mg/L

Question 4

why is the dead sea considered a natural spa? describe it’s salinity and mineral content.

Answer 4

it has a salinity of 34%
53% MgCl2
37% K
8% NaCl

Question 5

how much of earth’s water is freshwater?

Answer 5

2.5%

Question 6

how is earth’s fresh water distributed?

Answer 6

Groundwater 20%
surface water 1%
glaciers and ice caps 79%

Question 7

what are the different sources of surface fresh water?

Answer 7

Lake & ponds
rivers & streams
wetlands

Question 8

what are aquifers?

Answer 8

porous, spongelike formations of rock, sand, or gravel that hold water.
there are 2 types: unconfined and confined aquifers

Question 9

what’s the difference between an artesian well and a typical well?

Answer 9

artesian well: groundwater from the confined aquifers layer, does not require pump
well: groundwater from the unconfined aquifer layer, requires pump

Question 10

what is pollution

Answer 10

the release of matter or energy that causes undesirable impact on the health and wellbeing of humans or other organisms, into the environment.

Question 11

what does point sources mean?

Answer 11

A single and identifiable source, location, or point

Question 12

what does non-point sources mean?

Answer 12

pollution is cumulative, arising from multiple input over larger areas

Question 13

what are the 6 main forms of water pollution?

Answer 13

1. Toxic chemicals
2. Pathogens and water borne disease
3. Nutrient pollution
4. Biodegradable watse
5. Sediment
6. Thermal pollution

Question 14

Explain how toxic chemicals pollute fresh water

Answer 14

• pesticides, petroleum pdts, synthetic chemicals
• poison animals and plants, change aquatic ecosystems
• human health problems

Question 15

explain how pathogens and water borne diseases pollute fresh water

Answer 15

• pathogenic viruses and bacteria from human/animal waste
• enter drinking supplies
• human health problems

Question 16

explain how nutrient pollution pollutes fresh water

Answer 16

• eutrophication and hypoxia
• due to excess N and P
• algae bloom
• drive down O2 levels
• too low to support aquatic life

Question 17

explain how biodegradable wastes pollutes fresh water.

Answer 17

• wastewater from toilets, showers, sinks, washing machines

Question 18

explain how sediments pollute fresh wtaer

Answer 18

• expose soil to erosion
• When clear water receives heavy influx of sediments, aquatic habitat changes dramatically

Question 19

explain how thermal pollution pollutes fresh water

Answer 19

• human/industrial activities raise water temperature
• decrease water’s ability to hold dissolved O2
• water stored in dams (warm surface layer and cold bottom layer)
• older dams draw cold water from bottom of dam causing cold water pollution

Question 20

what are the sources of groundwater pollution?

Answer 20

1. natural forms of chemicals
2. waste leaching into aquifers
3. pathogens and other pollutants seeping through wells
4. leakage of carcinogenic pollutants
5. leakage of radioactive compounds
6. agricultural activities

Question 21

what are plasticizers?

Answer 21

a chemical added into plastic to improve flexibility, durability and workability

Question 22

what are some actions to reduce pollution?

Answer 22

• treating drinking and waste water
• constructing wetlands
• WHO guidelines
• USA clean water act
• China water pollution control law
• HK’s water pollution control ordinance cap. 358