Chapter 4: Terrestrial Environment

Question 1

What are the four major differences from the aquatic environment?

Answer 1

1. water balance
2. structure for living on land
3. temperature and environmental variability (more variety on land, water holds temp well)

Question 2

Desiccation:

- living cells are __-__% water

Answer 2

-75-95%

Question 3

Desiccation:

- terrestrial organisms must protect themselves against ??

Answer 3

water loss

Question 4

Desiccation:

• Water balance?
• *also what is desiccation

Answer 4

• adaptations to prevent water loss. Must replace water that is lost via eating and drinking for animals, vascular transport for plants.
• *if you’re not in an area very humid you are losing water, so terrestrial animals have to protect themselves from water loss aka desiccation

Question 5

Describe the photosynthetically active zone on land?

Answer 5

• if you’re a plant you have to be adapted to how much light is actually reaching you i.e. are larger organisms like tree’s blocking some of your exposure to UV? How do you compensate?

Question 6

Is all light reaching the surface used by plants?

Answer 6

nope

Question 7

Some light can be ___ depending on the type of light and the type of leaves. Eg?

Answer 7

• reflected
• 6-12% of PAR is reflected by leaves, ~70% of IR and ~3% of UV
• *PAR= Photosynthetically active radiation

Question 8

There may be a ____ influence on light depending on the composition of the forest.

Answer 8

• seasonal

ie decidious plants

Question 9

Plant cover can do what with respect to light?

Answer 9

• intercept light depending on the relationship between leaf area and available light.

Question 10

Attenuation of light is described by?

Answer 10

Beer’s Law

** ALi= e^-LAIixk

Question 11

What is the medium of plant growth?

Answer 11

soil

Question 12

Soil controls the fate of what in terrestrial environment

Answer 12

water

Question 13

Is soil just an abiotic environment?

Answer 13

• no! contains billions of bacteria, fungi and animals (habitat)

Question 14

How does soil formation begin?

Answer 14

• weathering of rocks

Question 15

What are some variations in physical characteristics of soil?

Answer 15

• colour, texture (particle size), moisture, depth and methods of soil formation

Question 16

Wtrt soil ___ holding capacity depends on particle size.

Answer 16

moisture

** soil will help absorb water or help drain it (important for how much available water)

Question 17

What is available in soil aside from water for plants?

Answer 17

• chemical nutrients in soil available for uptake and use by plants

Question 18

Why is soil not as important in oceans?

Answer 18

• because nutrients are just suspended in the ocean !