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