SOILS
10cm are form in 2.000 years
The available land air per habitat
Will reduce by half by 2050
Hectares of land chage of owner every year
This people are the poorest
So they distroy forest because they need land to live
In a world cost
The demand of soils is of 490 billion dollars
Because soils are invaluable
In 2011
24 million tones were lost
3.4 tonnes per person were used
Every year 13 million hectares of forest are cut down
adding manucultures and farming, which acelerates erosion
Soil distribution
This one is proadic and patchy
It have a group of factors that influence soils
CLORPT
Time
Parent material
Volcanic rock
Relief
Change in elevation
Orfganisms
Climate
Clasification of soils
Oxisol
Low fertility but very development horizon
Rainforest soil
Mollisol
Most fertile soil is the best for agriculture
is a grassland soil
Aridisol
Is a desert soil and has low amount of water
Ultisol
located in subtropical and humid places
Iron makes it red
Alfisol
Is in Broadleaf and decideous fores
Spodosol
Is low fertility and coniferous forest
Gelisol
Is pernafrost and is more close to the surface
Inceptisol
Slightly more horizon development
Entisol
Has no development of soil horizon
Layers of the soil
R horizon
Where there is only rock
C horizon
Where bedrock is degrading into soil
B horizon
Farthes plant roots will go for soils
A horizon
Where real surface soil is and there are organisms
O horizon
Is the uppermost and y more organic
They can be considered as
Silt
is between the other two
Sand
is the biggest
Clay
is the smallest
this ones have dofferent propeties
If a soil is more silt has characteristics of the other two soils
Is a soil is more sand will be worse retain of water bur easily plant growing
If a soil is more clay will retain more water but difficulty on plants growing
if a soil has 25% sand, 40% silt, 35% clay
is considered as Clay loam
created by rocks disposed by
Erosion
Smaller socks are carried from bigger rocks
By wind or water
Weathering
Breaking rocks into smaller rocks
By phisical or chemical process