文档介绍：I
Cereal Crops:
Economics, Statistics and Uses
Cereals the period 1960-1989 are shown diagrammatically
in Fig. .
Cereals are the fruits of cultivated grasses,
members of the monocotyledonous family
Production
Gramineae. The principal cereal crops are wheat,
barley, oats, rye, rice, maize, sorghum and the The world production of wheat, barley, oats,
millets. rye, rice (paddy), maize, sorghum and millet
Cereals have been important crops for thou- was estimated at 1233 million tonnes (Mt) in
sands of years; indeed, the essful production, 1969-1971, rising to 1652 Mt in 1981, and to
storage and use of cereals has contributed in no 1784 Mt in 1987-1989.*
small measure to the development of modern The total world production of the eight major
civilization. cereals in 1987-1989 would have been sufficient
to provide approximately 350 kg of cereal grain
per head per annum, or about 960 g per head per
World crops
day, if shared equally among the entire world
population. This is a slight reduction on the figure
Area estimated for 1981, which was 370 kg of cereal
The area occupied by the eight cereals averaged grain per head per annum, indicating that the
665 million ha over the 3-year period of increase in total world production is not quite
1969-1971, and increased to 719 M ha on average keeping pace with the increase in world population.
in the period 1979-1981. There was a slight fall, The average human consumption of cereals is
to an average of 691 M ha, in the period only about one half of these figures, as a variable
1987-1989. Between 1965 and 1989 the area proportion is used for other purposes, mainly
under wheat, barley, maize, rice and sorghum animal feed, industrial processing, and seed, and
has shown a small increase, whereas the area there is considerable wastage. Thus, in 1984-1986,
under oats, rye and millet has decreased slightly. of a world total domestic supply of 1677 Mt of all
The