Unit 2 - AOS1 - Indicators of pollution

Question 1

Indicator

Answer 1

“Are what is measured to assess the condition of an environment “

Question 2

Examples of what indicators may measure

Answer 2

Population, mean temp, rainfall, biomass burnt, threatened species

Question 3

Good indicators

Answer 3

“ measurements that work for the environment that your in”

Question 4

Categories of environmental indicators

Answer 4

Physical
Chemical
Biological
Socioeconomic

Question 5

Purpose of environmental indicators

Answer 5

• Good environmental indicators demonstrate link between human activity and its consequences
• Shows a cause-and-effect relationship

Question 6

Ecological niche

Answer 6

” Description of an organism’s structure and functional role in an ecosystem”

Question 7

Generalists (niche of species)

Answer 7

Species that have a broad ecological niche and feed on many kinds of food

Question 8

Specialists (niche of species)

Answer 8

Narrow ecological niche and feed on very few food types.

Question 9

Tolerance range

Answer 9

“The limited range of physical adn chemical conditions which an organism can survive:

Question 10

Tolerance limit

Answer 10

“The point at which the physical and chemical condition becomes harmful to an organism”

Question 11

Threshold of pollutants

Answer 11

“The point at which a certain level or concentration is reached, and an effect is observed.”

Question 12

Things that can cause the threshold to change

Answer 12

• The type of pollutants
• The environment the organisms inhabits
• The stage the organism is at in its lifecycle (development stage baby)
  (threshold depends on tolerance limit)

Question 13

Limiting factors

Answer 13

“Any condition that approaches or exceeds an organisms limit of tolerance”

• A single factor can determine whether a particular species can survive in an area

(e.g. temp, annual rainfall, concentration of an element)

Question 14

Meaning behind Indicators and Standards

Answer 14

• Scientists have determined target or standards for many environmental indicators to allow us to identify healthy environments
• The stands allow us to make judgments by comparing the measurements from indicators against the standards.

E.g. if we can identify an organisms threshold level for salinity it allows us to set standards for water quality.

Question 15

Water quality standards for salinity

Answer 15

For water to be at excellent standard for us to drink, it needs to have an electrical conductivity (EC) reading lower than 800 micro siemens per cm.

Question 16

Turbidity

Answer 16

“The measure of fine particles suspended in the water column”

• Determines level of light penetration through water
• Indicates soil erosion

Measure: in NTU’s (nephelometric turbidity units) using a nephelometer.

Monitoring: turbidity tube or secchi disk (picture) keep putting it down into water until you can’t see it anymore.

Question 17

Light intensity (Water indicators)

Answer 17

“The measure of the amount of sunlight reaching the surface”

• Low light intensity -> lower photosynthesis rate -> less producers
• Also terrestrial -> such as top of trees compared to base sheltered plants under trees

Measure: Secchi disk (linked to turbidity -> water)

Question 18

pH (water indicators)

Answer 18

“the measure of acidity or basicity of water or soil”

• Range between 1-14 (1-6 acidic, 7 neutral, 8-14 basic)

Affects: Biological processes, Rates of chemical reactions, Toxicity of substances

Soil: used to monitor a range of processes (acidification, salinity, acid sulphate concentrations –> used for soil fertility

Question 19

Dissolved Oxygen (water indicators)

Answer 19

“The amount of oxygen dissolved in water”

• Effected by temp, salinity, microorganism abundance, exposed surface water, turbidity level, biomass of photosynthetic organisms

Freshwater levels of DO:-
- > 5 ppm can support a wide variety of organisms.
- 1 – 5 ppm are sufficient for some living things (not ideal for fish).
< 1 ppm, indicates there is probable little to no life in the water.