Exam 15: Global Soils

Organic matter rapidly decomposes in areas of warm, moist climates, so these soils have little humus.

Soil horizons may be missing because:

The Deccan Plateau of India is noted for vertisols.

The amount of water a soil can hold against the pull of gravity is its:

Positively charged plant nutrient ions are called:

The process of water dissolving and carrying the material downward through the soil layers is called:

Soil orders form four groups.

The finest soil particle sizes are called:

On the illustration, the soil at F is:

A distinctive layer of soil, more or less horizontal, set apart from other layers by differences in physical or chemical composition is known as a soil _____________.

A black soil that is high in clay content, associated with savannas, and noted for its wet and dry climate is the:

The soils BEST associated with tropical rainforest areas such as the Amazon basin and the wet-dry tropical climate area are:

Decalcification is the removal of calcium carbonate from a soil layer.

The process of accumulating materials from above is called:

The soil that develops in moist, equatorial, tropical, and subtropical zones under long stable conditions is:

Soil texture is important because it influences the:

The clumping of soil grains is the soil's:

The build-up of calcium carbonate in the soil is called:

Soils that naturally are poor in fertility and able to sustain crops for only several years are:

__________are soils of cold regions that are underlain by perennially frozen ground, or permafrost.