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present plans to deepen and widen channels in major harbors are realized the 
amount of dredged material produced annually will increase substantially. 
RECEIVING ENVIRONMENTS - LAND VS. SEA 
Although in recent years sponsors of dredging projects have made much use 
of land sites for disposal purposes, the environmental, economic, and so- 
ciologic problems associated with such use are increasing. The spread of 
population to coastal areas has usurped land that was once available for 
disposal adjacent to the ports. Equally important such population shifts 
have usurped agricultural land, covering it with homes, airports, parks, and 
the like. On a worldwide basis shortage of food has become an increasingly 
critical issue for man. 
FOOD PRODUCING POTENTIAL - LAND VS. SEA 
The plant biomass of the sea is about 15,000 times smaller than that of the 
land. And, more important, is the observation that the oceans with about 
three times the area of the land produce only about cne-third as much bio- 
mass per year as do terrestrial plant communities. Moreover, the oceans 
produce no more than 1.5 percent of the world's food supply. There is every 
likelihood that this percentage will decrease, for the world's population is 
increasing while the yield of food from the sea has leveled off. In 1973 
world landings of ocean products totaled 72.4 million metric tons. This was 
down from the record 74.7 million metric tons reported for 1976. 
OCEAN DISPOSAL APPEARS TO BE A GOOD SOLUTION 
The ocean has a tremendous capacity for assimilating sediments without meas- 
urable ill effects. The amount of sediment that man will ever have to dis- 
pose in the ocean in a year is a small fraction of what it has been receiv- 
ing annually via rivers. In the United States the Mississippi River dis- 
charges in a normal year about one million cubic yards of sediment per day. 
Yet one of the most productive U.S. fisheries is located in the area of this 
discharge. It is ‘important that we now give consideration to the ocean 
values that we shall be able to protect by using “special care". 
