Influence of Ground Structure and Seepage Characteristics on Formation and Maintenance of Spring Water Marsh

Abstract

A rainfall infiltration analysis was performed for one year using daily weather data to clarify the formation and the mechanism of maintenance of a spring- water marsh located on a gravel formation. The ground was divided into the soil layer and gravel layer, with these both composed of a vertical percolation layer，lateral drainage layer，and barrier soil layer. The analysis showed that the largest water discharge from the ground was that from the soil layer, by evapotranspiration. Water storage in the gravel layer was about 20 times that in the soil layer. Water was stored in the gravel layer during the wet season and discharged slowly in other seasons. The existence of a thick gravel layer was the cause for continuous drainage throughout the year.