soil fertility quiz 2

Question 1

what are the necessary macronutrients

Answer 1

carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium and sulfur

Question 2

what are the necessary micronutrients

Answer 2

iron, manganese, zinc, copper, boron, molybdenum, cholrine

Question 3

what is a soil colloid?

Answer 3

include soil particles measuring 2 micrometers or less in diameter

Question 4

what makes up a collodial component of a soil?

Answer 4

clays and humus

Question 5

what is an ion

Answer 5

an atom or molecule in which the total number of electrons is not equal to the total number or protons, giving the atom a net positive or negative charge. ions can be created by both chemical and physical means

Question 6

what is a cation

Answer 6

and positively charged ion

Question 7

what is an anion

Answer 7

a negatively charged ion

Question 8

what are the most common soil cations?

Answer 8

calcium, magnesium, potassium, ammonium, hydrogen, and sodium

Question 9

cations in soil solution are readily available for plant uptake while cations on CEC sites are ______________________

Answer 9

moderately available for uptake

Question 10

if the cation is actually part of the soil structure, it will do what?

Answer 10

slowly be available to the plant

Question 11

what are some common annions?

Answer 11

chlorine, nitrate, sulfate, and phosphate

Question 12

anions can have more than one ___________ and may be combinations of ____ with _________

Answer 12

negative charge, elements with oxygen

Question 13

what is CEC? describe it

Answer 13

cation exchange capacity, the amount of exchangeable cations per unit dry weight of soil

Question 14

CEC depends on what

Answer 14

soil structure

Question 15

what soil processes do CEC’s affect?

Answer 15

weathering of soil minerals, nutrient absorption by plants, leaching of electrolytes, buffering of soil pH

Question 16

what is BC? describe it

Answer 16

Buffer capacity, the ability of a soil to resist change

Question 17

CEC determines what?

Answer 17

how you can supply many important nutrients

Question 18

what is the current USGA spec for clay percentage?

Answer 18

3%

Question 19

what are some characteristics of low CEC soils

Answer 19

• low nutrient levels
• rapid changed in nutrient levels
• leaching
• salinity build up
• pH changes
• difficulty in monitoring nutrient status and levels
• establishment problems

Question 20

what are nitrogen problems in low CEC soils?

Answer 20

• leaching of NH4+
• maintaining adequate N levels for growth
• N carrier effect on pH
• NO3- can also leach quickly due to high percolation rates

Question 21

what is the primary problem in low CEC soils

Answer 21

potassium

Question 22

major buffering occurs where

Answer 22

at the CEC sites

Question 23

when is the best time to determine your soil CEC

Answer 23

at construction