test.

Question 61 (5 points)

 

What is cation exchange capacity and why is it such an important soil component?

Question 62 (5 points)

 

Discuss the ecological effects of poor aeration and waterlogged soil conditions; include details on how the microbial community is changed, the plant, animal and microbial availability of soil nutrients, how soil color changes, changes in soil off-gasses, and potential plant root/shoot problems.

Question 63 (5 points)

 

Define isomorphic substitution: Include a definition, where it occurs, discuss what ions might be included in isomorphic substitution, and name three clays in which their charge is dependent on isomorphic substitution.

Question 64 (4 points)

 

List and discuss the four main principles that govern cation exchange.

Question 65 (3 points)

 

Explain the role texture plays in the speed, sorption, and movement of water in soils.

Question 66 (3 points)

 

Discuss at least three environmental benefits of wetlands.

Question 67 (3 points)

 

Why do no-till farmers sometimes have to wait a few more days to get in the field in the spring than farmers who use traditional till?

Question 68 (3 points)

 

Explain the role texture plays in the speed, sorption, and movement of water in soils.

Question 69 (3 points)

 

Describe soil water potential (including approximate quantities) as it moves from soil, up thru a plant, into the atmosphere, and back to the soil in the form of precipitatio

Question 70 (3 points)

 

Why would farmers in arid regions utilize the practice of leaving a particular field fallow for part of a potential growing season? What ramifications both positive and negative might this have on soil moisture and conservation?

Question 71 (3 points)

 

Explain the pros and cons of artificial drainage. How might it be positive from an agronomic perspective, but negative from an environmental one?