Lecture 4: Ecosystem Ecology

Question 1

Ecology

Answer 1

the study of the relationships between organisms and their environment–both living and non-living

Question 2

Trophic Levels

Answer 2

Elements of food chains–energy passes from one organism to another
each link in the food chain
Producer (1st)
Primary Consumer (2nd)
Secondary Consumer (3rd)
Tertiary Consumer (4th)
Decomposers

Question 3

Keystone Species

Answer 3

The keystone to an ecological community–if the keystone species disappeared then the are large impacts on the entire ecosystem
ex) sea otter eating urchins that would otherwise destroy the ocean environment
punch over their weigh in terms of their environmental effect on the systems

Question 4

Carrying Capacity

Answer 4

the maximum population size of a species that its environment can sustain

Question 5

Limiting Factors

Answer 5

slow and stop exponential growth–s-shaped logistic growth curve

Question 6

Dead Zones

Answer 6

caused by excessive nitrogen and phosphorus from human activities which cause algal blooms that strip dissolved oxygen from the water, make the area unliviable

Question 7

Eutrophication

Answer 7

excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which cases a dense growth of plant life and death of animal life from lack of oxygen

Question 8

Ecosystem Services

Answer 8

processes that help regulate (clean) our environment an benefit people
pest control, erosion control, cycling nutrients, natural buffers

Question 9

Positive feedback loop

Answer 9

when system output causes the system to change in the same way and drives it further toward one extreme or another–compounding changes

Question 10

negative feedback loop

Answer 10

system changes and moves in one direction; which causes the system to move in the other direction–stabilizing the system