E.—ORGANISATIONS NON GOUVERNEMENTALES / E.—NON-GOVERNMENTAL ORGANIZATIONS

Abstract

The departure of ground water from equilibrium with calcite is being studied in central Florida. Measurements of pH, temperature, and concentration of bicarbonate made in the field are used with standard laboratory analyses of water samples to calculate an ion activity product (K _iap ) for calcium carbonate. The calculated Kiap is compared with the equilibrium constant (Keq) for calcite to determine the departure from equilibrium. The calcium concentration is lowest in the area of the highest piezometric surface. Some of the highest concentrations of bicarbonate are in the area of low calcium. In about half of the area of study, the water is undersaturated with respect to calcite. This indicates that solution of limestone can occur several hundred feet below the water table.     

E.—NON-GOVERNMENTAL ORGANIZATIONS / E.—ORGANISATIONS NON GOUVERNEMENTALES

Abstract

It is shown that a thermodynamic analogy can be set up for structurally cyclic as well as for noncyclic river nets that satisfy Horton's law of stream numbers. In the latter case, the microcanonical formalism of statistical thermodynamics has to be used.     

2.—FORECAST OF SUMMER FLOOD WAVES OF THE SIÓ AND KAPOS RIVERS FROM PRECIPITATION

Abstract

Flood forecasts for the Sió and Kapos Rivers in Hungary have been made using gage relations. In order to increase the forecast time advantage procedures have been developed for predicting maximum stage using precipitation data and other variables including soil moisture index.

The paper describes the methods for developing forecasting relations involving three variables and four or more variables. The procedures are restricted to flood events caused by summer and autumn-precipitation (ice and snow-melt floods excluded).