193 
TABLE 2,—ESTIMATED FISH PRODUCTION IN THE 3 OCEAN PROVINCES, 
NEE 
Primary Fish 
production production 
[tons Corgante Trophic Efficiency [tons (fresh 
Province carbon)] levels (percent) weight)] 
Oceanitcsad 88 Sus ee ee eaee 16.3109 5 10 16105 
Coastal: 2225.) RIOR a seeeet = ee. . ee 3.6109 3 15 12107 
Upwelling= css. sees ies seeeeset = 2-2 -- 2-28. 0.1109 1% 20 1210? 
Ot ae eece ree oa ono ween ew ew a aw es ner enn oe seme enee tera o<osaaceceecc=~5 24107 
Note: Table 2, Ryther (1969). 
It is exactly at the land-sea interface that pollution and exploitation 
by man is causing severe and perhaps irreversible destruction to one of 
his major food supplies. The potential for cultivating coastal regions to 
feed future generations can be greatly diminished by the continued 
practice of dumping highly toxic materials in the form of industrial 
and agricultural wastes into these waters. 
Our society has the misconceived attitude that the environment is 
infinitely capable of producing goods for man and dispersing his wastes. 
It is easy to say that the ocean can handle pollutants, even resistant 
ones such as chlorinated hydrocarbons (DDT and its derivatives), and 
radionuclides (plutonium 239, strontium 90, cesium 137, etc.), by its 
great dilution powers. However, such statements ignore the fact that 
there are natural processes which can concentrate diluted.pollutants to 
a point of being lethal to some organisms. 
Anoxic basins provide an excellent example of the process of concen- 
tration. Anoxic basins act as sediment traps because of sluggish circu- 
lation and lack of benthic animals. Any pollutant which enters this 
system is also trapped and thus concentrated. In this instance, how- 
ever, as long as the water column in the basin does not overturn, such 
pollutants are-not a hazard to the surrounding environment; but the 
possibility of an overturn is always a real danger. sa 
Another example is the concentration of DDT and its derivatives, 
DDD and DDE, in food chains. Figure 5 shows that DDT is taken up 
by plankton and_ other plants from sea.water. These small organisms 
serve as a food source for smallfishand zooplankton which are in turn 
eaten by larger fish and sea birds and so on. DDT is resistant to meta- 
bolic degradation, and will be passed up the food chain becoming 
concentrated in more complex organisms at the top of the food chain 
(Woodwell,, 1967). For example, humans have concentrated DDT to 
the extent that female milk is unsafe for infant consumption (Radonski 
and Deichman, 1969). The concentration of DDT in the ocean is less 
than a part per trillion; the final concentration in man is on the order 
of 10 to 50 parts per million (Wondwell, 1967). 
