The aquatic thermal capsule

Summary

1.	The air phase of the thermal capsule during both summer and winter must be considered “still air” as opposed to the circulation of spring and fall.
2.	Heat change by high-low temperature change or sensible heat and evaporation-condensation are in close agreement (3204 and 3281 cal cm−2 for the heating period).
3.	Vertical mixing under the “still air” mass fell below values reported for waters of the hypolimnion.
4.	The effects of periodic ice and vegetative mat cover on heat transfer have not yet been ascertained.
5.	Although Fourier analysis was not used to determine thermal conductivity in the mud of LaRue Swamp, the diffusivity was 0.0026 cm2 sec−1, compared to 0.0035 cm2 sec−1 for Lake Mendota and 0.004 cm2 sec−1 for Lake Hula.
6.	The heat budgets of Lake Hula and LaRue Swamp sediments were 1400 cal cm−2 and 1023 cal cm−2, respectively.

This study is a contribution of the Pine Hills Field Station and the Department of Botany, Southern Illinois University at Carbondale, Illinois, U. S. A.