In the Nile River Valley, man built a large dam for economic and
industrial reasons and soon found that the fish population in the
Mediterranean Sea decreased; that the number of disease bearing aquatic
snails increased; and that the fertility of the valley itself was
diminished. Closer to the site of this conference, we can examine the
results of the construction of the Welland Canal connecting Lakes Erie
and Ontario. The completion of the canal allowed the predatory sea
lamprey eel to enter the interior lakes and quickly reduce the fisheries
of trout and other commerical species. Soon the smaller alewife
flourished since they had always served as food for the commercial
fisheries. The sudden increase in these fish has often resulted in
massive kills, quite common along the shores of Lake Michigan. In
recent years ecologists have introduced the coho salmon which has
thrived and cut back on the alewife population, These fish, however,
have had to be removed from commercial markets from time to time because
of high DDT concentrations in their bodies.
These two cases are significant examples of how fragile the
environment is and how careful one must be when he deals with it.
Impact on the environment can also be measured simply in terms of the
ever increasing number of people that must interact with it. For
example, in the past forty years the National Parks of the United States
have had to accept a number of visitors that has ranged from 3 million
in 1940 up to 150 million in 1970. How man plans for and copes with
changes such as these will, to a great extent, determine the quality of
our environment in the years to come.
Alvin Toffler in the introduction of his book Future Shock
discussed change in this manner:
"... I gradually came to be appalled by how little is
actually known about adaptivity, either by those who
call for and create vast changes in our society, or by
those who supposedly prepare us to cope with those
changes. Earnest intellectuals talk bravely about
‘educating for change' or 'preparing people for the
future.' But we know virtually nothing about how to
do it. In the most rapidly changing environment to
which man has ever been exposed, we remain pitifully
ignorant of how the human animal copes."
THE PROBLEM
To see how the human animal copes and how the environment fares
with his coping, man has begun to employ remote sensing devices to
provide him with environmental data. These sensors have many limita-
tions but may prove to be the key to global pollution monitoring in the
years to come. To say that they are capable of detecting or "con-
trolling" pollution is often not true and many times unfair to the
sensor for we have yet to define what pollution is. Definitions will
vary from nation to nation, province to province, or person to person.
The man dependent on soft coal to heat his house or run his factory will