Desert Soils Flashcards

Study Notes

Soil Composition and Layers

Surface Litter: Comprises leaves, branches, animal excreta, carcasses, mushrooms, and decomposing organic matter.
Topsoil/Humus: Formed from the decomposition of surface litter with minerals from weathered rocks.
Subsoil: Contains fragmented rock materials, including sand, clay, gravel, and silt.
Parent Material: Refers to the bedrock that lies beneath the soil layers.

Factors Influencing Soil Formation

Parent Material: Affects permeability, mineral content, soil texture, and nutrient availability.
Climate: Influences weathering processes, precipitation levels, and temperature variations.
Organisms: Contribute organic matter and play a critical role in nutrient cycling and recycling.
Relief: Encompasses aspects like altitude, slope angle, and orientation which affect soil development.
Human Activity: Includes the impacts of agriculture, urbanization, and land management practices.
Time: It can take approximately 400 years to generate 10mm of soil, requiring 3000-12000mm for sufficient agricultural depth.

Characteristics of Desert Soils

Dry Conditions: Minimal moisture retention leads to unique soil characteristics.
Composition: Dominated by sand and mineral-rich content; the surface often forms a crust.
Colorful Appearance: The lack of rainfall prevents leaching, leading to rich and varied mineral hues.
Thin Layers: Desert soils typically have very limited thickness.
Stoniness: Often stony if deflation processes occur, which remove finer particles.

Soil Types in Deserts

Entisol: Young, mobile soils resembling sand dunes; lack defined horizons due to constant movement.
Aridisol: Characterized by a light color due to accumulated silica, gypsum, and calcium carbonate deposits.

Salinisation Process

Occurs when high temperatures cause soil moisture to evaporate, pulling salts to the surface through capillary action.
These salts can be toxic, rendering the land unusable, whether resulting from natural conditions or irrigation practices introduced to dry regions.

Description

Test your knowledge of desert soils with these flashcards. Each card provides a key term related to desert soil composition and its definition. Enhance your understanding of this unique ecosystem and its characteristics.