Soil exam #2

What is the main function of soil in Earth's systems?

Soil connects all spheres of earth's functions.

What is hydroponics?

A system for growing plants without soil, where nutrient-rich water supports the plants.

Which elements make up more than 95% of all living tissues?

Carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus (CHONSP).

What are the three components that make up the composition of ideal soil?

Sand, silt, and clay.

What is Soil Organic Matter (SOM)?

The organic part of soil that is a food source for microorganisms and affects soil structure and fertility.

What does 'weathering' refer to in geology?

The breakdown of rocks into smaller pieces or their transformation into chemically altered versions of themselves.

What are the five soil forming factors according to Hans Jenny's CLORPT?

Climate, Organisms, Parent material, Relief (topography), and Time.

What is the difference between erosion and weathering?

Erosion is the transport of rocks and sediments, while weathering is the breakdown or transformation of these materials.

What is the significance of the O horizon in soil?

It consists of organic material not mixed with minerals and is crucial for soil health.

What is 'bulk density' in soil science?

The mass of soil per unit volume, including the air space.

How does soil texture affect water retention?

Finer textured soils have greater surface area and can retain more water than coarser soils.

What is soil aeration?

The process of replacing soil air with atmospheric air to maintain healthy soil conditions.

How does soil pH affect nutrient availability?

Soil pH can influence how efficiently plants can absorb nutrients, often with an optimal pH around 6.5.

What are sodic soils and why are they problematic?

Sodic soils are high in sodium, which can lead to poor soil structure and water movement.

What is cation exchange capacity (CEC)?

The ability of soil to hold and exchange cations, affecting nutrient availability for plants.

What role does water play in soil chemical reactions?

Water acts as a reactant in many soil chemical processes, including weathering and nutrient transport.

What are the four soil forming processes?

Additions, Losses, Translocations, and Transformations.

What is bioturbation?

The disturbance of soil by living organisms, influencing soil structure and nutrient cycling.

How does parent material impact soil characteristics?

The type of parent material determines the mineral composition and properties of the soil.

What is soil permeability?

The ability of soil to transmit water through its pores.

What is a soil profile?

A vertical section of soil showing different horizons from the surface to the parent material.