The approaching completion of the acidification phase of the Little Rock Lake Project in Spring 1991 provides a rare and valuable opportunity to examine recovery from long term stress at the whole-ecosystem scale. Since 1983, Little Rock Lake, Wisconsin has been the site of a large-scale experiment designed to detail the effects of acid deposition on aquatic ecosystems. Two basins of the lake were separated with a curtain and the pH of one basin was lowered with sulfuric acid from an original value of 6.1 in three, two year stages to target values of 5.6, 5.1 and 4.6. Both basins have been sampled in parallel for a broad range of limnological parameters to provide baseline support for an evaluation of the Lake's recovery following acidification. System recovery will be examined on two nested levels. Drs. Frost and Kratz will monitor the lake's chemical recovery as it's pH and ANC return towards pre-acidification conditions. Within this chemical framework, the PIs will examine biological recovery by focusing primarily on the zooplankton community. Patterns of species return will be documented within the two lake basins and processes underlying those patterns will be examined through smaller-scale experiments. Drs. Frost and Kratz are respected and productive scientists. The institutional support and facilities available for this project are outstanding.
