Shoreline Algal Survey of Bellaire, Clam and Torch Lakes Antrim County, Michigan -- Fall 1971

Abstract

This survey is a follow-up investigation to the preliminary study completed in the spring of 1971. A comparison of that survey to the results of this survey is expected to reveal persistent sources of nutrient influx. The theory behind the survey is that in oligotrophic situations such as those found in Torch Lake nutrients are not in great enough concentrations to support a large growth of algae for any extended period. Thus any persistent algal growth along the shoreline must be the result of outside nutrient influx such as a faulty tile field. The accuracy of such a survey, except in isolated locations, is not extremely great by virtue of the high number of variables involved. Along the more populated stretches of shoreline, it is difficult to determine the exact source of pollution because such factors as seepage„ gradient and currents influence the point at which the algal growth is found; i . e . , algal growth in front of one house does not mean that it was not a result of seepage from a close neighbor.