Question

Given below are two statements
Statement I: The surface of a 'pedon' is roughly polygonal
Statement II: The surface area of a pedon ranges from \( 1\ m^2 \) to \( 10\ m^2 \)
In light of the above statements, choose the correct answer from the options given below

• A. Both Statement I and Statement II are true
• B. Both Statement I and Statement II are false
• C. Statement I is true but Statement II is false
• D. Statement I is false but Statement II is true

Hint:

A collection of similar pedons is called a "Polypedon." A polypedon is the real-world individual that we classify as a "Soil Series."

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
A "pedon" is the smallest three-dimensional volume of soil that can be recognized as an individual soil body.
It contains all the horizons and properties of the soil at that location and is the basic unit of soil sampling and classification.

Step 2: Detailed Explanation:
Statement I is true. Because soil peds and structural units often develop along planes of weakness, the boundary of a pedon is conventionally represented as roughly polygonal in plan view.
This shape allows for the efficient "tiling" of pedons into a larger "polypedon," which represents a soil individual or a mapping unit.
Statement II is also true. The dimensions of a pedon are defined such that it is large enough to show the nature of all horizons and their variability.
The minimum surface area of a pedon is \( 1\ m^2 \).
If the horizons are cyclical or vary significantly in thickness, the area is increased, but the maximum limit for a single pedon is set at \( 10\ m^2 \).
If the variability exceeds what can be contained in \( 10\ m^2 \), the soil is considered a complex of different individuals rather than a single pedon.

Step 3: Final Answer:
Both statements correctly define the geometry and scale of a pedon as used in soil survey and taxonomy.