Rocks and Soil Flashcards
studying rocks, soil and effects
Soil composition
consists of weathered rock, decayed organic matter, mineral fragments, water, air and organic matter
Humus
dark material made from organic matter, provides nutrients
Loam
soil with equally mixed proportions of sand, silt, and clay
steep slopes
causes dirt, rock and water to slide cause of gravity
little vegetation
causes loose rocks and dirt to blow around cause of the lack of roots/plants
water
washes away loose soil/rock
wind
blows away loose soil and rocks
Agriculture
topsoil erodes when crops are removed and fields are left without plants, nutrients gets depleted from the same plants being planted every year
Forest Harvesting
cutting down trees, exposes the soil, soil is thin and topsoil doesn’t last long
Overgrazing
livestock are left on the same field too long, they eat all the vegetation
strip mining
leaves rock exposed, topsoil is discarded
No till farming
the stacks of the crop are left over winter, new crops are planted without tilling the stocks under
Contour farming
Planted on the natural relief of the land
Terracing
on steep slopes, stairs are carved out to slow down water run-off
Cover crop
planting a winter crop, no only reduces erosion but using the right plants can put nutrients back into the soil
Pasture Rotation
livestock graze on a field for a short period, they are moved to a different field to give time for the other field to recover
Crop rotation
planting specific types of crops in a different spot each year, this helps the nutrients of the soil
soil profile
is made up of all the layers of soil
A horizon
topsoil, top layer, may be covered with litter
B horizon
middle layer, lighter in color, less fertile, has the most leached material
C horizon
bottom horizon, made from weathered rock, contains little leaching and organic matter
Igneous
formed from the cooling and solidification of molten rock, contains large crystals. Ex: basalt, granite, and obsidian
Metamorphic
starts out as some other type of rock.
forms when rocks are subject to high heat, high pressure, hot fluids with minerals or any combination of those factors
tough with curved or straight layers
Ex: Quartzite, slate, and marble
Sedimentary
starts as sediment, normally carried by a river, then dumped into a large body of water.
forms by accumulation of sediment, then cementation occurs and forms a sedimentary rock
most often have distinctive layers.
Ex: Sandstone, limestone, and shale
