lecture 3: Environmental Heterogeneity

Question 1

Climate can exist on different spatial scales including:

Answer 1

Global → Regional → Local → Micro

Question 2

aquatic environment divided by

Answer 2

divided by salinity:
saltwater and freshwater
* Divided by depth

Question 3

direct vs indirect impact of light in aquatic environment

Answer 3

Direct impact: plants
– Plants require sunlight for photosynthesis
– Plants are restricted to top 100 m

Indirect impact: animals
– Herbivores are restricted to depths where plants reside

Question 4

deep water organism adaptations

Answer 4

Lack pigment
* Large eyes (maximum light-gathering ability)
* Organs that produce light (bioluminescence)
higher metabolic activity of animals

Question 5

thermocline

Answer 5

region with most rapid decline in temperature
separates cold and warm water

Question 6

water less than 4 degrees Celsius

Answer 6

less dense (becomes ice so floats aka keeps cold water at surface while warm water stays down so organisms can still live)

deeper water stays 4 degrees Celsius

Question 7

aquatic environment- oxygen and how do deep sea organisms get some O2

Answer 7

more oxygen at surface (since this is where source of o come from in aquatic environments)

o2 enters in water by diffusion or photosynthesis

mixing of water column can break down gradient (help distribute o2, helping deep sea organisms)

aka wind, currents, etc

Question 8

terrestrial environment greatest constraint

Answer 8

desiccation- drying out/ access to water

Question 9

is the foundation for terrestrial life and why

Answer 9

soil
- medium for plant growth
-provides vertical structure for animal life
- controls fate of water in terrestrial environments
-provide habitat for decomposers

Question 10

Moisture-holding capacity of the soil is critical for availability of:

Answer 10

-water
– chemical elements dissolved in soil water

Question 11

What causes variation in the moisture-holding capacity?

Answer 11

Climate

Type of parental material

Topography (slope surface less water retained than flat surface)

Aspect (north, moist and south, dry)

Presence/absence and type of vegetation

Question 12

Vegetation alters microclimates:

Answer 12

• Light (through shading)
• Temperature (through shading)
• Moisture (through usage)
• Wind movement
• Structure – habitat for animals

Question 13

Environmental heterogeneity

Answer 13

= differences in environmental conditions across a landscape or over time.