CSES 2040 Test 2 - Questions With Fully Explained
Solutions
The relative amount of which two gases can be a good indication of the status
of soil aeration? Correct Answer - O2 and CO2
The concentration of soil CO2 is about __________than the atmospheric air.
Correct Answer - 10X - 100X
In the absence of free O2, which of the following elements (molecules) can act
as terminal electron acceptors? Correct Answer - NO3, SO4, CO2
Under optimum conditions, as temperature increases by 10°C, bio-chemical
reactions will ________________. Correct Answer - Double
A dry soil is a good insulator because it has: Correct Answer - Low thermal
conductivity and high heat capacity
a measure of cations held on soil colloid exchangeable sites Correct Answer
- CEC (cation exchange capacity)
The two sources of negative charges in silicate minerals are: Correct
Answer - Isomorphous substitution and pH dependent charge
Ammonium acetate is used to determine soil CEC that was fertilized with
NH4+ by the displacement method. In this situation, the correct CEC will be:
Correct Answer - underestimated
Comparatively, which of the following soil colloid contains the highest amount
of negative charge (Cmolc/kg)? Correct Answer - soil humus (organic
matter)
Soil pH is a ___________________ because it affects many biochemical reactions in
soils. Correct Answer - Master variable
A soil with a pH of 5.0 has __________ H+ compared to a soil with a pH of 7.0.
Correct Answer - 100X
, The concentration of which elements will increase as soil pH decreases from
6.0 to 4.0. Correct Answer - Mn, Fe, Zn
Which of the following liming material has the highest calcium carbonate
equivalent (CCE) relatively? Correct Answer - CaO
Liming will increase soil pH by Correct Answer - introducing more basic
cations
Alkaline soils have ________ OH-, HCO3-, CO3--, and H+ than acidic soils.
Correct Answer - less
Most of the salt affected soils of the contiguous US lay _________ of the
Mississippi River. Correct Answer - west
ESP, ESR and SAR are measures of __________ status in soils. Correct Answer -
sodium
Water evaporation leads to ___________ accumulation since ______________ does
not evaporate under normal conditions. Correct Answer - salt, salt
Sodic soil can be reclaimed by adding Correct Answer - calcium (often
gypsum)
fix atmospheric N2, produce antibiotics, mineralize N, P, and S Correct
Answer - functions of soil microbes
You will find ____________ in desert soils, water submerged soils, in humans and
in the air. Correct Answer - microbes
Microbial population is __________________ related to soluble food sources.
Correct Answer - positively
soil __________ are doing most of organic matter decomposition Correct
Answer - flora
more than ________ of the global water is contained in the oceans Correct
Answer - 95%
Solutions
The relative amount of which two gases can be a good indication of the status
of soil aeration? Correct Answer - O2 and CO2
The concentration of soil CO2 is about __________than the atmospheric air.
Correct Answer - 10X - 100X
In the absence of free O2, which of the following elements (molecules) can act
as terminal electron acceptors? Correct Answer - NO3, SO4, CO2
Under optimum conditions, as temperature increases by 10°C, bio-chemical
reactions will ________________. Correct Answer - Double
A dry soil is a good insulator because it has: Correct Answer - Low thermal
conductivity and high heat capacity
a measure of cations held on soil colloid exchangeable sites Correct Answer
- CEC (cation exchange capacity)
The two sources of negative charges in silicate minerals are: Correct
Answer - Isomorphous substitution and pH dependent charge
Ammonium acetate is used to determine soil CEC that was fertilized with
NH4+ by the displacement method. In this situation, the correct CEC will be:
Correct Answer - underestimated
Comparatively, which of the following soil colloid contains the highest amount
of negative charge (Cmolc/kg)? Correct Answer - soil humus (organic
matter)
Soil pH is a ___________________ because it affects many biochemical reactions in
soils. Correct Answer - Master variable
A soil with a pH of 5.0 has __________ H+ compared to a soil with a pH of 7.0.
Correct Answer - 100X
, The concentration of which elements will increase as soil pH decreases from
6.0 to 4.0. Correct Answer - Mn, Fe, Zn
Which of the following liming material has the highest calcium carbonate
equivalent (CCE) relatively? Correct Answer - CaO
Liming will increase soil pH by Correct Answer - introducing more basic
cations
Alkaline soils have ________ OH-, HCO3-, CO3--, and H+ than acidic soils.
Correct Answer - less
Most of the salt affected soils of the contiguous US lay _________ of the
Mississippi River. Correct Answer - west
ESP, ESR and SAR are measures of __________ status in soils. Correct Answer -
sodium
Water evaporation leads to ___________ accumulation since ______________ does
not evaporate under normal conditions. Correct Answer - salt, salt
Sodic soil can be reclaimed by adding Correct Answer - calcium (often
gypsum)
fix atmospheric N2, produce antibiotics, mineralize N, P, and S Correct
Answer - functions of soil microbes
You will find ____________ in desert soils, water submerged soils, in humans and
in the air. Correct Answer - microbes
Microbial population is __________________ related to soluble food sources.
Correct Answer - positively
soil __________ are doing most of organic matter decomposition Correct
Answer - flora
more than ________ of the global water is contained in the oceans Correct
Answer - 95%
