LANDS

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LANDS
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Land

• .. can be defined as a disaggregated and
  variable thickness superficial layer produced by
  the mechanical or physical weathering of the
  stone what covers the Earth's crust.
• Land forming, or paedogenesis, is a combined
  effect of physical, chemical, biological and
  anthropogenic process produces on land original
  materials.
• LAND IS ALWAYS IN A CONTINUOS PROGRESSION.

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LAND uses
People uses land for developing several
activities
For planting and sowing, For building (houses,
infrastructures) For minerals extracting, For
wastes placing
Human activities and earth ageing generate in the
land surface a series of impacts as
Land erosion, Excessive exploitation, Pollution, I
nfertility, Ecological degradation,
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LAND composition
In the land the three state of the matter
disaggregated in two different compounds coexist
as following
Inorganic Air (O and CO2), water and mineral
compounds, as rock fragments (sand, gravel, mud,
boulders, ) and mineral salts (sulphates,
carbonates, phosphates )
Organic organic matter what has not been
transformed ( leafs, excrements, animal
carcasses,) and several micro organism
(bacteria and fungus) which form the humus.
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LAND cross section
is the structure of the soil where we can
observer several layers which receive the name of
levels or horizons.
A HORIZON OF LIXIVIATION It contents a little
rate of mineral salts. B HORIZON B OF
PRECIPITATION, with high rates or calcium,
aluminium and iron salts. C HORIZON Formed by
chemical and mechanical weathering fragments of
the underlying rock. D BED ROCK, rock layer
situated in a variable deep what is whole and
waterproof.
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LAND evolution
Several factors have influence in land evolution.
The more representative are following
WEATHER determinates the type of rock-bed
weathering, and it is the most influent factor in
land evolution. TOPOGRAPHY land gradient,
erosion and orientation to the sun are several
relevant factors for land evolution. BED ROCK
NATURE the characteristics of the bed-rock
determinate the mineral compounds of the
land. BIOLOGICAL ACTIVITY The abundance of
organism which allow decaying, transform the
organic matter of the land. PASSING OF TIME
Actually, and due this factor, the lands are
considered as no renewable resource, because the
land destruction exceed its regeneration capacity.
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LANDS