Temperature, oxygen and heat-budgets of six small western Irish lakes

SUMMARY. 1. Temperature and oxygen were examined in six small western Irish lakes (areas 2–110 ha) in 1981, 1982 and 1984.
2. The four deeper lakes (= 6–11m) stratify stably in the same manner as some well-known stratifying lakes in Britain. Windiness (due to proximity to the ocean) seems generally to be reflected in the lakes by the presence of a sharp thermo clinic. Considerable variation in the pattern of stratification occurs from year to year.
3. Two shallow lakes (= 4.1 and 2.7m) stratify only in periods of warm, calm weather.
4. Annual heat-budgets range from 4.1 kcal cm⁻² to 13.7 kcal cm⁻². There is a strong linear relationship between mean-depth and annual heat-budget.
5. Oxygen depletion is severe in the more productive lakes.