Question

question 9
2 pts
select the statements about soils (below) that are true.

• soils are dynamic (ever changing), and are home to many life forms.
• soils develop very quickly
• soils develop slowly over time, as rocks weather and organic matter decays.

question 10
2 pts
which of the following is the thickest?

• lithosphere (crust)
• pedosphere (soil)
• earth - core to crust

Explanation:

Question 9

• For "Soils are dynamic (ever changing), and are home to many life forms": Soils have biological activity, nutrient cycling, and physical/chemical changes, so this is true.
• For "Soils develop very quickly": Soil formation involves weathering (slow) and organic matter accumulation (slow), so this is false.
• For "Soils develop slowly over time, as rocks weather and organic matter decays": Soil formation is a long - term process with weathering of rocks and decomposition of organic matter, so this is true.

• Lithosphere (crust): The lithosphere (crust) is relatively thin (continental crust ~30 - 70 km, oceanic ~5 - 10 km).
• Pedosphere (soil): The pedosphere (soil) is very thin, usually a few meters at most.
• Earth - core to crust: The distance from the Earth's core to the crust is extremely large (the radius of the Earth is about 6371 km, with the core - mantle boundary at ~2890 km depth from the surface). So the Earth - core to crust is the thickest. The selected option "Pedosphere (soil)" is incorrect. The correct answer should be "Earth - core to crust".

Answer:

• Soils are dynamic (ever changing), and are home to many life forms.
• Soils develop slowly over time, as rocks weather and organic matter decays.

Question 10