CSES 2040 - Test 3 UPDATED ACTUAL
Questions and CORRECT Answers
The amount of CO2 that enters the air atmosphere annually is greater than that leaves the pool
and as the result the atmosphere CO2... - CORRECT ANSWER - has been increasing
During photosynthesis, green plants use _____ and _____ to make starch (C6H12O6). Hence,
increases in atmospheric CO2 is expected to increase starch production. - CORRECT
ANSWER - CO2 and H2O
Soil contains almost ________ as much carbon as the vegetation and the atmosphere combined. -
CORRECT ANSWER - Twice
As soil organic matter content increases, its density will: - CORRECT ANSWER -
decrease
The microbial decomposition of organic compound to yield inorganic molecules such as N, P,
etc., is called: - CORRECT ANSWER - Mineralization
Immobilization process will result in net __________ of soluble nutrients such as N, P, etc., in
the soil. - CORRECT ANSWER - loss
A typical green plant contains ___________% carbon on oven-dry basis. - CORRECT
ANSWER - 40
To avoid a nitrate depression period, the minimum amount of nitrogen (kg) that must be added to
an organic residue that contains 1500 kg of C and 30 kg of N will be: - CORRECT
ANSWER - 30
The C:N ratio of a typical Ap or B soil horizon is approximately: - CORRECT ANSWER -
, Describes the increased decomposition of a relatively stable soil humus under enhanced
microbial activity when fresh plant residue is added to a soil. - CORRECT ANSWER -
Priming Effect
No till farming practices will __________organic carbon of surface (0-5 cm depth) soil
compared to plowed soil. - CORRECT ANSWER - Increase
If organic carbon content of a soil is 2.92%, its organic matter content will be about: -
CORRECT ANSWER - 5.02
Long term application of manure to soil as demonstrated by the Rothamstead (1850) in England
and the Morrow plot (1875) of Illinois experiments will ____________ soil organic carbon. -
CORRECT ANSWER - Increase
Plants get their C as CO2 from: - CORRECT ANSWER - The atmosphere
T or F: Nitrogen (N2) is an inert gas because it reacts with O2 and forms NH3 under normal
conditions. - CORRECT ANSWER - False
T or F: The world will run short of nitrogen since there is limited nitrogen ores and no other
natural reserve exists to replace it. - CORRECT ANSWER - False
T or F: Most of the nitrogen fertilizer applied to soil is taken up by plants as NH4+ and NO3-
and as the result, the fertilizer nitrogen use efficiency is in the range of 90-100%. - CORRECT
ANSWER - False
Gain of nitrogen includes: - CORRECT ANSWER - Lighting and mineralization
T or F: Many years application of ammonium nitrate fertilizer to soil will have no impact on its
pH under normal conditions - CORRECT ANSWER - False
Questions and CORRECT Answers
The amount of CO2 that enters the air atmosphere annually is greater than that leaves the pool
and as the result the atmosphere CO2... - CORRECT ANSWER - has been increasing
During photosynthesis, green plants use _____ and _____ to make starch (C6H12O6). Hence,
increases in atmospheric CO2 is expected to increase starch production. - CORRECT
ANSWER - CO2 and H2O
Soil contains almost ________ as much carbon as the vegetation and the atmosphere combined. -
CORRECT ANSWER - Twice
As soil organic matter content increases, its density will: - CORRECT ANSWER -
decrease
The microbial decomposition of organic compound to yield inorganic molecules such as N, P,
etc., is called: - CORRECT ANSWER - Mineralization
Immobilization process will result in net __________ of soluble nutrients such as N, P, etc., in
the soil. - CORRECT ANSWER - loss
A typical green plant contains ___________% carbon on oven-dry basis. - CORRECT
ANSWER - 40
To avoid a nitrate depression period, the minimum amount of nitrogen (kg) that must be added to
an organic residue that contains 1500 kg of C and 30 kg of N will be: - CORRECT
ANSWER - 30
The C:N ratio of a typical Ap or B soil horizon is approximately: - CORRECT ANSWER -
, Describes the increased decomposition of a relatively stable soil humus under enhanced
microbial activity when fresh plant residue is added to a soil. - CORRECT ANSWER -
Priming Effect
No till farming practices will __________organic carbon of surface (0-5 cm depth) soil
compared to plowed soil. - CORRECT ANSWER - Increase
If organic carbon content of a soil is 2.92%, its organic matter content will be about: -
CORRECT ANSWER - 5.02
Long term application of manure to soil as demonstrated by the Rothamstead (1850) in England
and the Morrow plot (1875) of Illinois experiments will ____________ soil organic carbon. -
CORRECT ANSWER - Increase
Plants get their C as CO2 from: - CORRECT ANSWER - The atmosphere
T or F: Nitrogen (N2) is an inert gas because it reacts with O2 and forms NH3 under normal
conditions. - CORRECT ANSWER - False
T or F: The world will run short of nitrogen since there is limited nitrogen ores and no other
natural reserve exists to replace it. - CORRECT ANSWER - False
T or F: Most of the nitrogen fertilizer applied to soil is taken up by plants as NH4+ and NO3-
and as the result, the fertilizer nitrogen use efficiency is in the range of 90-100%. - CORRECT
ANSWER - False
Gain of nitrogen includes: - CORRECT ANSWER - Lighting and mineralization
T or F: Many years application of ammonium nitrate fertilizer to soil will have no impact on its
pH under normal conditions - CORRECT ANSWER - False
