Some long‐term trends in water quality of rivers and lakes

Abstract

In these times when we are trying to determine our environmental position and the course we are taking, it is desirable to employ every means for assessment available. One such means is to consider measurements of environmental quality that have been maintained over a period of many years. The opportunities for doing this, however, are limited since we have only recently begun to realize fully the importance of monitoring our environment. Thus few environmental records are available for more than a decade.