Agronomy Soil Science and Fertility 2

Question 1

Soil organic matter improves soil structure primarily by doing what?

Accepted Answer

Promoting aggregate formation

Answer

Organic matter binds soil particles into aggregates, improving aeration, water infiltration, and tilth.

Question 2

Which micronutrient deficiency commonly appears as interveinal chlorosis on young leaves?

Accepted Answer

Iron

Answer

Iron deficiency causes interveinal chlorosis on young leaves because iron is immobile in plants.

Question 3

What does the term 'base saturation' refer to in soil science?

Accepted Answer

Percentage of CEC occupied by base cations

Answer

Base saturation is the percentage of a soil's CEC occupied by basic cations such as Ca²⁺, Mg²⁺, K⁺, and Na⁺.

Question 4

Which soil order is commonly found in the Corn Belt and is highly productive for agriculture?

Accepted Answer

Mollisol

Answer

Mollisols have thick, dark, organic-rich A horizons and high natural fertility, making them ideal for corn and soybean production.

Question 5

Liming a soil primarily corrects which soil problem?

Accepted Answer

Excessive acidity

Answer

Agricultural lime (calcium carbonate) neutralizes soil acidity by reacting with hydrogen ions to raise pH.

Agronomy Practice Test