Soil quiz

soil

broken down rock and organic material

soil composition

air, water, soil particles (weathered rock/mineral & organic material)

percentages of composition of soil

air = 25% water = 25% rocks/minerals = 45% organic matter = 5%

Relative soil particle sizes

gravel, sand, silt and clay

gravel

biggest soil particle size

sand

2nd biggest soil particle size (coarse, medium, fine)

silt

2nd to smallest soil particle size

clay

smallest soil particle size

organic material

remains of once living organisms

after of organic material

after it gets into soil, fungi and bacteria will cause it to decay/decompose

decomposition

creates soil that contains the nutrients plants need in a form that they can use to carry out life processes

horizons

soil layers

layer o

organic matter

layer a

topsoil

layer b

sub soil

layer c

weathered rock/parent rock

fertile measure through underground

up = most fertile deep = less fertile

years to form soil

1000s of years

fertile

best for plant growth

soil degradation

soil's inability to grow plants

ways to prevent erosion

windbreaks, terraces, contour plowing, no-till farming, and argo forestry

windbreaks

reduce wind speed at ground level, an important factor in wind erosion

terraces

prevent downhill erosion

contour plowing

plowing across the slope of a hill instead of up and down the slope

no-till farming

a crop is harvested without turning over the soil

argo forestry

planting rows of trees with a cash crop