الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
the area of egypt is about 1 million km2 of which only about 6 million acres are under cultivation, the remaining land is barren, desert. therefore, the most important two factors limiting soil productivity are water and organic matter.
in the old days, egyptian farmers depended entirely on farmyard manures to supply plant nutrients neded for crop production.