Bio 346 - Freshwater Eco. (Chpt 25) --> Zoobenthos

Question 1

Epifauna

Answer 1

The fauna of the sediment surface

Question 2

Infauna

Answer 2

Those of the surgical sediment

Question 3

Hyporheic fauna

Answer 3

Is part of a continuum that ranges from the fauna of the sediment surface of lakes to the floodplain fauna of the groundwater adjacent to many lotic systems

Question 4

Macrobenthos

Answer 4

Consists of the organisms that live at the bottom of a water column and are visible to the naked eye

Question 5

Meibenthos

Answer 5

Are small benthic invertebrates that live in both marine and freshwater environment
- They are medium size

Question 6

Megabenthos

Answer 6

Largest invertebrates

Question 7

How would estimate rates of community production and respiration or contaminant flow in food webs?

Answer 7

Size based community descriptions together with info on the systematic changes in metabolism with size

Question 8

What makes for the best estimate of biomass?

Answer 8

Density

- Can use fewer samples

Question 9

What happens to biomass specific reduction as biomass increases?

Answer 9

Decreases

Question 10

What are 4 different categories of feeding groups?

Answer 10

1. Filter feeding
2. Deposit feeding
3. Scarping
4. Shredding

Question 11

What kind of feeders are dominant when turbulence is low?

Answer 11

Deposit feeders and collectors are predominant

Question 12

What kind of feeders are dominate in shallow flowing water and turbulent littoral?

Answer 12

Scrapers

Question 13

What kind of feeders are dominate in streams?

Answer 13

Shredders

- Do well due to low primary production

Question 14

Depositional boundary depth

Answer 14

Separate zones of fine and coarse sediment, thermocline

Question 15

What happens at greatest macrophyte density?

Answer 15

Greatest zoobenthic species richness

Question 16

Littoral zone

Answer 16

• Often dominant by macrophytes
• Most productive regions of lakes
• Largest number of animal species, biomass, diversity a d secondary production
• Subdivided into 3 zones (upper, middle and lower littoral)

Question 17

Upper littoral

Answer 17

Reaches from the shoreline sprayed by waves in wind-exposed lakes to where the emergent macrophytes disappear

Question 18

Middle littoral

Answer 18

Extends down from the lower edge of the upper littoral zone to the depth where rooted submerged macrophytes disappear

Question 19

Lower/ sublittoral zone

Answer 19

Extends from from the lower edge of the middle littoral zone to the bottom of the euphoric zone

Question 20

What is the bottom on the littoral zone best indicated by?

Answer 20

Deposition Boundary Depth (DBD)

Question 21

What does DBD stand for?

Answer 21

Deposition boundary depth

Question 22

Deposition boundary depth

Answer 22

Separates the zones of fine and course sediments

Question 23

As macrophyte biomass increases, what do the zoobenthos become more associated with?

Answer 23

Plants

- Rather than sediments

Question 24

Profundal zone

Answer 24

Is a deep zone of an inland body of freestanding water (like a lake or pond) located below the range of effected light penetration

Question 25

What is growth rate highly dependent on? (3 things)

Answer 25

1. O2 levels
2. Primary production
3. How much nutrients are sinking to the bottom

Question 26

Profundal community biomass increases with the increase of what?

Answer 26

Trophic status

- Followed by decrease at epilimnetic Chl-a [ ]

Question 27

What are the 4 negative effects on profundal zones?

Answer 27

1. Sampling depth
2. Lake demand depth
3. Slope
4. Colour

Question 28

What are 2 positive effects on profundal zones?

Answer 28

1. Mean depth: max depth ratio

2. Temp

Question 29

What do top down and bottom up effects influence?

Answer 29

Community composition