*10 Most Abundant Elements In Earth's Crust*
- Oxygen - 46.1%
- Silicon - 28.2%
- Aluminium - 8.23%
- Iron - 5.63%
- Calcium - 4.15%
- Sodium - 2.36%
- Magnesium - 2.33%
- Potassium - 2.09%
The above fact suggests that a lot of aluminum gets blown into the
atmosphere in the form of dust. I must question whether the tiny amount
used in cloud seeding would have an appreciable effect upon the biology of
organisms living on Earth's surface.
From Ecotoxicology of Aluminum
<http://www.pjoes.com/pdf-87442-21301?filename=21301.pdf>:
Aluminium contents in such plant food products as fruits and vegetables,
and animal products: meat, poultry, eggs do not exceed 10 mg/kg. Among
plant products, cereal grams naturally contain higher quantities of
aluminium than fruits and vegetables, but products manufactured from them
bear less aluminium than full grain. Spices and herbs accumulate very high
amounts of aluminium, reaching sometimes 2000 mg/kg, while tea even up to
5000 nig/kg of dry leaves. Among milk products, the highest aluminium
contents are observed in ripened cheese and cheese spreads [21]. FAO/WHO
committee established maximum weekly aluminium intake at 7 mg/kg of body
weight [that's about 500mg for an adult], whereas the results of many
studies indicate that we often ingest even 10-100 mg of aluminium a day.
*Aluminium Influence on Plants* Numerous studies conducted for many years
have shown that aluminium can be both beneficial and harmful for plants,
causing even death. The beneficial effect of aluminium on plants consists
of the stimulation of iron absorption by root system, increased absorption
of phosphorus, prevention of toxic effects of copper and manganese and
plant protection against phytopathogenic fungi. Furthermore, aluminium
increases plant resistance to unfavourable environmental conditions, such
as drought, high and low temperatures, soil salinity [4]. On the other
hand, detrimental aluminium effect on plants manifests itself as crop
decrease which is caused by changes in the morphology of root system,
inhibition of its elongative growth, root callosity, reduced number of
rootlets, and dying away of growth cone. Moreover, aluminium phytotoxicity
is expressed as disturbances in the absorption of mineral substances
(changes in plasma membrane structure and function), inhibition of cell
divisions and elongation, and disturbances of important processes
determining normal growth of the root system [9,32].
Randy Oliver
Grass Valley, CA
530 277 4450
ScientificBeekeeping.com
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