Photo AI
Explain how weathering, leaching and podzolisation have impacted the characteristics of soil. - Leaving Cert Geography - Question 16 - 2012
Question 16
Explain how weathering, leaching and podzolisation have impacted the characteristics of soil.
Worked Solution & Example Answer:Explain how weathering, leaching and podzolisation have impacted the characteristics of soil. - Leaving Cert Geography - Question 16 - 2012
Step 1
Weathering
Answer
Weathering is the process that breaks down rocks into smaller particles through physical, chemical, and biological means. This process significantly influences soil characteristics by:
-
Mineral Composition: As rocks weather, they release minerals into the soil. These minerals contribute essential nutrients, such as potassium, calcium, and magnesium, which are crucial for plant growth.
-
Soil Texture: The size and shape of the weathered particles affect the soil's texture, influencing drainage, aeration, and root penetration.
-
Soil Structure: The aggregation of soil particles, influenced by biological activity and organic matter, can enhance soil structure, promoting better water retention and root development.
Step 2
Leaching
Answer
Leaching is the process where soluble substances are washed out of the soil by percolating water. Its impact on soil characteristics includes:
-
Nutrient Loss: Essential nutrients, such as nitrates, can be leached away, resulting in nutrient-poor soils. This can affect plant health and yield.
-
Soil pH Alteration: Leaching can lead to changes in soil pH, making it more acidic and affecting nutrient availability.
-
Water Retention: The removal of certain minerals can impact the soil's ability to retain water, leading to drier conditions.
Step 3
Podzolisation
Answer
Podzolisation is a soil formation process characterized by the leaching of minerals and organic matter, resulting in a distinctive soil profile. Its effects include:
-
Eluviation and Illuviation: The upper horizon (A horizon) loses minerals and organic material (eluviation), while these materials accumulate in the lower horizon (B horizon). This can lead to a stratified soil profile, affecting root growth and water movement.
-
Acidic Conditions: The process contributes to the development of acidic soils, which can influence the types of vegetation that thrive in such environments.
-
Nutrient Imbalance: Podzolisation can lead to a depletion of basic cations, further impacting soil fertility.