Ecology - Plankton Ecology Model

Question 1

Plankton Ecology Model

Answer 1

A description of repeated community assembly, where the interactions are accurately studied.

Question 2

What interactions occur in PEG?

Answer 2

Herbivory, predation and competition.

Question 3

What controls biotic interactions?

Answer 3

Abiotic control factors at start and end of growing seasons.

Question 4

Importance of food availability…

Answer 4

Allows zooplankton development with a spring peak of grazing zooplankton with a then decline in phytoplankton biomass.

Question 5

Clear Water Phase

Answer 5

Is where algal biomass is markedly reduced in late spring-early summer.

Question 6

Importance of algal food quality…

Answer 6

Eutrophic systems experience increased algal biomass, with high inedible phytoplankton.

Question 7

What does light increase initiate?

Answer 7

Community assembly, whilst autumnal light decrease terminates it.

Question 8

Critical Depth

Answer 8

This describes how maximal mixing depth, allowing phytoplankton photosynthesis in excess of the respiration rate, thus positive growth rates.

Question 9

Strategies of overwintering…

Answer 9

Akinets, spores, resting eggs or diapause.

Question 10

How might copepods overwinter?

Answer 10

Accumulate lipid reserves

Question 11

How do zooplankton respond to overwintering?

Answer 11

Sink to lower depths.

Question 12

Example of seasonal responsiveness…

Answer 12

Spring bloom of phytoplankton with early emergence can increase potential biomass

Question 13

How does the clear water phaseemerge?

Answer 13

Grazing, where zooplankton consume the phytoplankton biomass resulting in a minimum proceeding their bloom in spring.

Question 14

Example of the parasitsm in the PEG…

Answer 14

Chytrid fungi..

Question 15

Example of food quality importance in zooplankton….

Answer 15

P or N limitation despite limit increase may prevent devlopment of communtieis

Question 16

Deep Chlorophyll Maxima

Answer 16

The region below surface water with maximum concentration of chlorophyll.

Question 17

What does DCM coincide with?

Answer 17

Zooplankton distribution, algae maxing in spring and autumn, lack of light in the winter and too much nutrient use in the summer despite the sunlight.

Question 18

How do herbivores increase exponentially?

Answer 18

Until density of the zooplankton exceeds the density of phytoplankton reproduction rate.

Question 19

What is present in the spring bloom?

Answer 19

Phytoflagellates and chlorphytes and centric diatoms

Question 20

Features of the summer time bloom..

Answer 20

Lower quality food as phosphorous becomes limited, thus diatoms dominate.

Question 21

What happens when diatom population silica is reduced?

Answer 21

Cyanobacteria blooms, resulting in nitrogen limitation and filamentous cyanobacteria which are inedible mostly.

Question 22

What does termination of winter result in?

Answer 22

Availability of nutrients and increasing light allowing phytoplankton to grow, especially fast growing ones.