Environmental Assements !

Question 1

Attributes of a good bioassay organism

Answer 1

1.common
2.life cycle appropriate to length of test
3.widespread distribution
4.biology is well known
5.lab friendly
sensitive

Question 2

Define bioassay

Answer 2

•take a representative animal, place it in containers with varying concentration of the effluent, see how much it takes to kill or harm the animal

Question 3

Define and give example

Sequential comparison index

Answer 3

• best used to detect a change or to indicate a problem, then do a more rigorous assessment
• based purely on diversity (number of different looking groups)
• Just out there to monitor change

Question 4

Define and describe “EPT”

Answer 4

• looks at EPT taxa (Ephemeroptera, Plecoptera and Trichoptera)
• assumes that these three orders are sensitive to pollution
• note that EPT and EPT/D can give different answers, depending on how many chironomids are present

Question 5

Ephemeroptera

Plecoptera

Trichoptera

Diptera

Answer 5

mayflies (sensitive)

stoneflies (sensitive)

caddisflies (sensitive)

true flies (tolerant)

Question 6

1. Shredders
2. Scrapers
3. Collecters
4. Predetors
5. Deposit

Answer 6

1. eat CPOM (leaves, etc.) (corse particulate organic matter)
2. eat aufwuchs (algae)
3. eath FPOM (dead stuff)
4. Eat other insects
5. eat mud

Question 7

Hilsenhoff’s family-level biotic index (FBI)

Whats this based on?

Answer 7

• this is an index based on sensitivity alone, not diversity
• based on sensitivity of families of invertebrates to organic pollution (i.e., may get erroneous results if used to detect heavy metal pollution)

Question 8

FBI formula

Answer 8

1.FBI = number in each family x tolerance of that family; sum product for all families, then divide by the total number of arthropods in sample (e.g., 100)