Dependence of Water Quality and Fish Habitat on Lake Morphometry and Meteorology

Abstract

The dependence of lake water temperatures, dissolved oxygen concentrations, and associated fish habitat characteristics on weather parameters and lake morphometry has been quantified from the output of verified water quality models. The models were applied to 27 Minnesota lake classes. Lake survey data for 3,002 lakes in the Minnesota Lakes Fisheries Database were used as a basis for the classification. The one-dimensional, deterministic, process-based water quality models used 25 years of daily meteorological data (1955–79) as input. The simulated characteristics of daily water temperatures, dissolved oxygen concentrations, and fish habitat during the open water season are correlated selectively with lake surface area, maximum depth, Secchi depth, annual normal air temperature, and saturated dissolved oxygen concentration. Annual normal air temperature and lake geometry ratio (the fourth root of lake surface area