Where does most organic matter in soil come from?
Plants (leaves, stems and roots, animals that died contribute too)
a) most plant roots are at the TOP layer of the soil.
b) the top layer is typically DARKER.
c) there are different layers called HORIZONS.
d) The HORIZONS form a soil profile.
Horizon A Top Soil consists of what?
humus, fewer rock and mineral particles, generally dark and fertile.
Horizon B Sub Soil consists of what?
lighter color, less humus, less fertile, contains material that moved down from top soil called leaching. (ex: water - seeps down - humus + carbon dioxide = acid.
Horizon C Rock Fragments consists of what?
partially fragmented rock, thickest soil, less organic material, less leaching.
What are Glacial Deposits?
a mixture of Clay, Silt, Sand, and Boulders. (CSSB). Many places on earth and covered by a thick layer of sediment that was deposited by glaciers. Extremely fertile soil
some soils are thick and red, brown with hard rock modules, and some have thick black A horizons.
lots of organic material, thicker/darker soil (A horizon), lots of grass contributes to it.
Terperate Forest soil
thinner A horizon than praire, tree roots and leaves deliver less organic material to deeper parts of soil
What additional factors affect soil type?
rock type - affects vegetation and time affects soil formation -.
How does soil erosion occur?
WATER & WIND. flowing water carries away sediment that used to be on the field/land.
What are some negative affects to Forest Harvesting?
removal of trees leaves soil exposed to weather increasing the damage to soil.
animals eating the vegetation results in slower plant growth, soil exposed to rain and wind and the result is erosion.
How des Excess Sediment contribute to erosion?
the build up of sediment clogs rivers, muddies the water, which can harm fish and other organisms.