IBESS Topic 5

Weather rock particles, gravel, sand, silt, clay, chalk, and minerals

Organic matter made from decomposition of living things

Climate, Organisms, Relief (elevation), Parent Material & Time

Octopi and Elephants Bake Chocolate Rocks

Litter layer of plant residues in relatively undecomposed form.

Top soil, rich in decomposed organic material

In this zone iron, clay and calcium, organic compounds, and other soluble compounds are leached out of the soil.

When eluviation is pronounced, a lighter colored "E" subsurface soil horizon is apparent at the base of the "A" horizon.

Leached nutrient and mineral accumulates in this zone

Layer of large unbroken rocks.

Bedrock

Organic and parent materials, precipitation, infiltration, energy

Leaching, uptake by plants, erosion

Deposition (reorganization of soil)

Decomposition, weathering, nutrient cycling

Organic matter, nutrients, organisms, minerals, air & water

• Cold, then warm temps

• Windy conditions

• Wet conditions

• Warm temps

• Plenty of organic material

• Wet conditions

• Warm temps

• Plenty of organic material

• Lots of sunlight

• Wet conditions

Small particles: fit, space, water

Rate at which air and water can flow through the layers in the soil

• Size of spaces in soil determines permeability

Measure of how much space between particles

• Fine particles = water retention

• Coarse particles = air retention

• More porous = more water and air

Movement of water up or down layer in soil

• Salinization

• Leaching

Large pore space: easily uprooted, water drains easily, cannot hold nutrients

Loamy soils → mix of particle sizes

• thin O horizons

• little organic input from shed vegetation

• nutrients are leached out or eroded away by heavy rainfall

Human activities:

• deforestation

• overgrazing by raised livestock

• poor farming practices

• removal of perennial grasses + annually harvested crops = few anchors to prevent erosion

• Appalachian and Rocky Mountain served as walls

Poor irrigation practices in arid regions result in salt deposits in topsoil

Heavy machinery and animals compact soil creating a denser soil; top soil becomes drier; seeds a prevented from taking root

• shelterbelts

• terracing

• contour ploughing

• no till/reduced tilling

• intercropping

• crop rotation

• silt fencing

Systematic planting of trees helps to buffer winds and reduce wind erosion

Creating stepped plateaus into a steep hillside increases farmable acreage while helping to reduce water erosion

Crops are planted perpendicularly to the slope which create physical barriers that help slow down runoff and reduce the amount of soil erosion

This practice creates less disturbed soil which means less erosion.

Increases total crop yields per acre & roots per area. More roots per year = less erosion

Rotating a nitrogen fixing crop through the fields increases soil fertility = bigger plants with stronger roots = roots holds onto soil helping to reduce erosion

• Hunting and Gathering

• Business (1500’s-1850’s)

• Green Revolution (1950’s-1970’s)

India: Undernourishment

Use technology (fertilizers, irrigation, specially bred strains of seed) to increase yield

Large scale production of crops and livestock for sale

Farming for self-sufficiency to grow enough for a family

• fossil fuels for mechanized equipment

• water for irrigation

• pesticides for pest control

• fertilizers to produce high yield

• deforestation + biodiversity

• monocultures that are susceptible to failure

• reduction of water availability

Process by which a fertile land changes itself into a desert by losing its flora and fauna

Aesthetic, taste preference, over consumption & misunderstanding (expiration date vs best by date)

Inadequate protection from bugs/rodents, refrigeration, and spoilage in transit

• Climate (availability)

• Cultural/Religious influences (Islam-no pork)

• Policies (tariffs on food)

• Socio-economic (explotation of workers in the search for affordability)

• food for family

• no surplus

• mixed crops

• cash cropping

• PROFIT!

• maximizing yield

• technology

• monocultures

Raising animals on grass and land not suitable for crops

Growing crops on good soil to eat directly or feed to animals

• Increase consumption of organically grown foods (local and seasonal)

• Polyculture!

• Reduce meat consumption

• Pollution Management (Buffer Zones)

Any organism that damages crops that are of value

Any plant that competes with valuable crops

Poisons that target pests

Kill insects

Kill plants

Kill fungi

The gradual accumulation of substances in an organism

Numerous techniques are used in combination to control pests to a manageable level (reduce pests to a tolerable level)