미국 플로리다주의 제한성 인디언리버라군에서의 물수지 및 체류시간

Abstract

The water balance calculation in the IRL shows that fresh groundwater discharge is the primary factor, with surface runoff from gauged and ungaged areas as the second freshwater contributor. Precipitation and evaporation are almost in balance for the entire IRL. Due to high freshwater discharge from groundwater, the annual net flow is outward from the IRL to the continental shelf of the Atlantic Ocean, resulting in a relatively short flushing time, denoted as T0.5 (50% flushing time) and T0.99 (99% flushing time). T0.5 and T0.99 without a tidal effect in the Northern IRL are 17 and 114 days, respectively, during the dry season. During the wet season, they are 10 and 65 days, respectively. Tidal flushing effects are considered in central IRL due to the proximity to Sebastian Inlet. In the Northern Central zone during dry season, T0.5 and T0.99 are 6 and 43 days, respectively and during the wet season 5 and 33 days. In the Southern Central zone they are 2 and 16 days for the dry season, 2 and 15 days for the wet season. High groundwater seepage into the IRL is considered to be a positive effect in maintaining relatively good water quality condition even with few narrow inlets.