The correct option is 2 and 3 only.
Explanation
Soil formation, or pedogenesis, is a complex process regulated by five basic factors: parent material, topography, climate, biological activity, and time. These factors are classified into active and passive control factors based on their role in the process.
Statement-wise Analysis:
- Statement 1 is Incorrect: Parent material is considered a passive control factor in soil formation. It provides the base material (mass) upon which other factors act. The active control factors are climate and biological activity, as they provide the energy (moisture and heat) and organic agents required to break down the parent material.
- Statement 2 is Correct: Soil formation depends significantly on the texture (size of debris) and structure (arrangement of debris) of the rock debris. These physical characteristics determine the surface area available for weathering agents and the permeability of the material, influencing the rate and nature of soil development.
- Statement 3 is Correct: Young soils often exhibit strong links with the type of parent rock because the soil-forming processes have not acted long enough to alter the original characteristics significantly. Over time, as weathering intensifies, the influence of the parent material diminishes, and climate becomes the dominant factor.
Key Takeaway:
In pedogenesis, Climate and Biological Activity are active factors that supply energy, whereas Parent Material, Topography, and Time are passive factors that provide the medium and duration for the process.