Slide 9 of 28
Notes:
One reason the fishermen's complaints were not immediately accepted is that the response of a lake to acid rain depends very much on local conditions. If the lake is fed by surface streams directly draining steep sided hills its pH may approach that of the rainfall. However, if the surrounding bedrock is basic (such as limestone) and the lake is primarily fed by ground water percolating through that rock, the pH of the rain will be irrelevant. Thus, rarely are ALL the lakes in a region similarly affected, and until the rainfall data were available other explanations always seemed equally plausible.