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It is now debatable if growing crops is a 'factory industry'
or whether it is still relevant to look at it in the traditional
way horticulture or agriculture (animals are dealt with in another
section)
There are two extreme examples of this:-
- Agriculture in some desert regions tries to control every
factor involving the plants. One can see the formation of a
new attitude - that the earth is what the plants stand on, but
that it contributes nothing to the nourishment of the plant.
All nutrients and water are brought to the plant by artificial
means, and the earth can be covered with plastic to reduce water
losses, and then largely ignored. (and this happens in temperate
lands also)
- Greenhouse crops. This attitude is already thriving in greenhouses,
where the grower attempts to keep the environment hermetically
sealed, so that light, water, nutrients and pests are entirely
under the control of the growers. This must be economic, otherwise
it would not be done !
These systems obviously work, but, they treat the field or greenhouse
as a closed system, and this is only partly valid. What happens
to the residues from sprays, what happens if water if polluted
and flows onto the next field ? It seems the growers treat it
as a closed system when they want to, and an open system as far
as pollutants are concerned.
There are reports that in the desert agriculture systems, there
are severe build-ups of salinity which eventually makes this type
of growing impossible if it is taken to an extreme.
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