Midterm 1

Question 0

What two parts does soil formation consist of?

Answer 0

(1) Production and accumulation of unconsolidated materials by weathering and movement
(2) Horizon development involving changes within the loose material over time

Question 1

What is soil formation?

Answer 1

Most soils are mineral soils formed from the weathering of solid rock masses into unconsolidated masses.

Question 2

What five factors are important to consider in soil formation?

Answer 2

Parent material, climate, biota, topography, time and the combination of all of these interactions

Question 3

What soils properties exist?

Answer 3

Physical (texture, structure, bulk density), chemical (pH, CEC, redox potential), and biological (respiration, food webs, fertility)

Question 4

What are the soil size classifications?

Answer 4

Less than 0.002 is clay
Between 0.002 and 0.05 is silt
Between 0.05 and 2.0 is sand

Question 6

What is soil bulk density?

Answer 6

The mass of a unit volume of dry soil with preserved air space

Question 7

What is biogeochemistry?

Answer 7

The core of this discipline deals with the cycling of biologically active elements. Chemistry of the surface of the earth in which organisms die and thrive mainly on the energy from the sun.

Question 8

Where are biogeochemical processes embedded?

Answer 8

The biosphere, lithosphere and hydrosphere

Question 9

What is the first law of thermodynamics? The second law?

Answer 9

(1) the total energy of an isolated system is constant; energy can be transformed from one form to another, but cannot be created or destroyed
(2) states that in a natural thermodynamic process, the system will find an equilibrium

Question 10

Name four conceptual advances in biogeochem.

Answer 10

• the role of carbonic acid in rock and soil weathering.
• the recognition that the primitive atmosphere was anaerobic, and that the gradual evolution of plants, accompanied by the locking tip of their residues as fossilized carbon, was responsible for an atmosphere rich in oxygen
• the recognition of the qualitative equality of the biosphere with the lithosphere, hydrosphere and atmosphere
• the view of humanity as a major geological agent

Question 11

How can hydroxyl radicals and ozone mix to produce more ozone? (Even in clean air)

Answer 11

NO2 + 02 = NO + O3

Question 12

How could you estimate the amount of Ozone in the atmosphere?

Answer 12

O3 (ppm) = 0.02 [NO2] / [NO]