Future of the Sea 

 Ronald I. Currie 



Organic matter in tfie sea is first produced 

 by tiie ptiotosyntiiesis of microscopic algae. 

 Ttiese plants are tlie food of small animals, 

 which in turn are eaten by progressively 

 larger creatures. Here, typical food chains 

 in coastal and oceanic waters are shown. 

 During their growth the algae make use of 

 certain salts, mainly nitrates and 

 phosphates, which are gradually transported 

 to deeper waters as the organisms sink, die, 

 and decompose. Upwelling of deep water 

 returns these salts to the surface, making 

 them available once more for plant growth. 

 In coastal waters there are generally more 

 algae but they are confined to shallower 

 layers; light needed for their photo- 

 synthesis does not penetrate so deeply as in 

 oceanic waters. Much of the material that 

 sinks to the bottom in coastal waters 

 supports an abundant fauna of bottom-living 

 animals, which in turn are the food supply 

 of many commercially important fishes. 

 Creatures shown at the bottom of the 

 illustration: 1. Pterygoteuthis, 

 2. Gigantactis, 3. Pachystomias, 

 4. Gastrostomus, 5. Bathothauma lyromma, 

 6. Aulastomatomorpha, 7. Vinciguerria. 



Since the time of Pytheas and his voyage beyond the Habitable 

 World we have come a long way. Present-day techniques enable 

 us to explore and chart the sea with an accuracy and mechanical 

 advantage undreamed of even in Magellan's time. Bathyscaphes, 

 electronic flash photography, seismic sounding, and other devices 

 are constantly helping us refine our knowledge of the sea's archaeo- 

 logical treasures, its plant and animal hfe, the chemistry and dy- 

 namics of its waters, and the geography and geophysics of its vast 

 floor. But what of the future of the seas? In what ways can man 

 harvest them for food, mine them for minerals, and harness them 

 for power? 



Since early times man has turned to the sea for food as good and 

 as plentiful as he could find on the land, although for. the most part 

 the land has been his chief supplier. However, as we have come to 

 face the fact that somewhat more than half of the world's popu- 

 lation is undernourished, and that our population is increasing each 

 year at a rate of about one per cent, we are thinking more and more 

 of turniag to the sea to help solve the problem of future food 

 supplies. But to what extent can the sea help us? According to 

 some specialists, the amount of organic matter produced in the sea 

 is about the same as the yield of good agricultural land. But what, 

 exactly, does this mean? And what bearing does it have on the food 

 we can take from the sea for direct consumption? 



All organic matter in the sea begins its production cycle by the 

 photosynthesis of plants - the tiny single-celled algae that float 



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