Soil, Water Cycle, Carbon Cycle

soil

The loose, weathered material on Earth's surface in which plants can grow.

Humus

material formed from decaying leaves and other organic matter

Decomposition

the state or process of rotting; decay.

Decomposer

An organism that breaks down wastes and dead organisms

soil texture

the soil quality that is based on the proportions of soil particles: clay, silt, and sand

soil horizon

The layer of soil that differs in color and texture from the layers above or below it.

soil fertility

A measure of how well soil supports plant growth.

Loam

Rich, fertile soil that is made up of about equal parts of clay, sand, and silt.

topsoil

Mixture of humus, clay, and other minerals that forms the crumbly, topmost layer of soil.

subsoil

The layer of soil beneath the topsoil that contains mostly clay and other minerals.

How do living things Affect Soil?

Form Humus and Mix the Soil.

C Horizon

forms as bedrock begins to weather and rock breaks up into smaller particles.

A Horizon

Forms as plants add organic material to the soil, and plant roots weather pieces of rocks

B Horizon

forms as rainwater washes materials down from the A horizon.

Worms affect soil by

forming humus and mixing the soil

Mice affect soil by

mixing the soil

Mushrooms/Fungi affect soil by

forming humus

Soil pH

is how acidic or basic a the soil is. Most plants prefer soil with. pH between 6 and 7.5

Soil that is mostly clay

may hold too much water and not enough air

Soil that is mostly Sand

may lose water quickly

Soil that is about an equal mix of sand, silt, clay

allows for water and air spaces

natural resource

anything in the environment that humans use

Soil Conservation

the management of soil to limit its destruction

crop rotation

a farmer plants different crops in a field each year

contour plowing

farmers plow their fields along the curves of a slope instead of in straight rows to reduce runoff and soil erosion.

conservation plowing

dead weeds and stalks of previous year crop are plowed into the ground to help return nutrients, retain moisture, and hold soil in place.

Precipitation

Any form of water that falls from clouds and reaches Earth's surface.

Condensation

The change of state from a gas to a liquid

Evaporation

The change of state from a liquid to a gas

Transpiration

Evaporation of water from the leaves of a plant

Respiration

breathing

Runoff

water that flows over the ground surface rather than soaking into the ground

Groundwater

water that fills the cracks and spaces in underground soil and rock layers

water cycle

The continuous process by which water moves from Earth's surface to the atmosphere and back

carbon emissions

Made from burning of fossil fuels, a major cause of global warming.

Photosynthesis

Plants use the sun's energy to convert water and carbon dioxide into sugars

Release Carbon

Animals, Factories

carbon sink

A natural environment that absorbs and stores more carbon dioxide from the atmosphere than it releases, which offsets greenhouse gas emissions.

Absorbs Carbon

Plants, Oceans,

carbon cycle

The organic circulation of carbon from the atmosphere into organisms and back again

water cycle

The continuous process by which water moves from Earth's surface to the atmosphere and back