Quiz 1 1999

Name____________________

CSS 315 Quiz 1 April 19, 1999

Choose the one best answer (2 points each) and mark the appropriate letter in the blank.

Match questions 1-6 with answers on right (answers on right may or may not be used more than once).

__1. Conversion of an inorganic solid form of a nutrient to an a. nitrification

inorganic soluble form by chemical reactions in soil b. denitrification

c. mass flow

__2. Conversion of NH₄⁺ to NO₃^- by biological activity in soil d. immobilization

e. weathering

__3. Conversion of an organic solid form of a nutrient to an f. mineralization

inorganic soluble form by biological activity in soil g. dinitrogen fixation

h. diffusion

__4. Conversion of an inorganic soluble form of a nutrient to an

organic solid form by biological activity in soil

__5. Conversion of N₂ from the atmosphere to amino acids and

proteins by biological activity

__6. Conversion of NO₃ to N₂ gas by biological activity in soil

7. Nutrients in the inorganic form in soil solution:

a. are unavailable to plants and are normally >95% of the total found in soil

b. are physiologically unavailable to plants

c. are chemically available to plants and are normally <5% of the total found in soil

d. are available to plants after conversion in soil to organic forms and constitute <5% of the total found in soil

8. Primary minerals:

a. Provides nutrients in a form that is normally directly available to plants

b. are important as the primary source of N in soils

c. are of sedimentary origin

d. are formed from volcanic activity and provide very low amounts of plant available forms of nutrients

Anhydrous ammonia and urea have what in common:

a. will be acid producing and volatilize on the surface of alkaline soils

b. will cause alkalinity and volatilize on surface of acid soils

c. can not be a source of nitrate for ground water pollution

d. are uncommon forms of commercial N fertilizer

Define the and differentiate terms for questions 9-11.

(3) 9. Essential element

(4) 10. Macronutrient vs. Micronutrient

(4) 11. Nitrate is a major concern for groundwater pollution and nitrogen fertilizer can be source of this nitrate. Describe four management approaches that can be recommended to use N fertilizer more efficiently by the crops to reduce nitrate leaching losses.