Lecture 4 - Guest Lecture

Question 1

Coastal (lacustrine) Marsh

Answer 1

highly productive, mostly herbaceous cover, primarily influenced by lake water levels

Question 2

Wetland Vegetation Zonation Pattern

Answer 2

floating/submerged -> emergent marsh -> meadow marsh

Question 3

Influences on Wetland Vegetation Zonation Pattern

Answer 3

hydrology (flooding and draw-down) and competition among wetland plants

Question 4

Vegetation Zonation

Answer 4

habitat diversity

Question 5

Cryptic Invader

Answer 5

looks similar to our native species

Question 6

Phragmites australis subsp. australis

Answer 6

cryptic invader, introduced in early 1900s, invasive species

• tall dense strands, sexual and asexual reproduction, large range of environmental tolerances

Question 7

Invasive Species

Answer 7

non-native species must be able to persist on its own and expand outside of its introduced range

Question 8

Phases of Invasive Species

Answer 8

introduction, colonization, establishment, spread

Question 9

Competitive Exclusion Principal

Answer 9

complete overlap in resources (two species can’t coexist)

Question 10

Classical Prediction for Invasive Species

Answer 10

high niche overlap = either repelled or very negative impacts

low niche overlap = establish, but won’t be very detrimental

Question 11

Niche Differentiation

Answer 11

reduces resource overlap and a species will limit itself more than a neighbour

Question 12

Fitness Differentiation

Answer 12

differences that favour one species always

Question 13

Treatment for Phragmites

Answer 13

application of glyphosate-based herbicide

Question 14

Efficacy for Treatment for Phragmites

Answer 14

1. suppression of Phragmites australis

2. return of native vegetation

Question 15

European Frog-Bit

Answer 15

secondary invasion, occurring with P. australis in control sites

small, free floating plant