TIDAL ESTUARY 



USUAL CONDITION 



35ppt 

 SEA WATER 



TEMPORARY 



(DURING HEAVY RAINS) 



35 ppt 

 SEA WATER 



SOILS 45 ppt 



SOILS 15-20 ppt 



DURING THE RAINY SEASON, SALINE CHANNELS 



SHIFTTO FRESHWATER;SALINE SOILS BECOME 



BRACKISH. 



CONDITIONS REVERSE AFTER RAINY SEASON. 



NON-TIDAL ESTUARY OR CLOSED LAGOON 



DRY YEARS 



WET YEARS 



35 ppt 

 SEA WATER 



35 ppt 

 SEA WATER 



SOILS 45 ppt OR MORE SOILS 0-20 ppt 



CLOSED LAGOONS AND THEIR MARSH SOILS 

 BECOME HYPERSALINE IN DRY YEARS, FRESH 

 TO BRACKISH IN WET YEARS. LAGOON 

 WATERS BECOME STAGNANT WITHOUT 

 TIDAL CIRCULATION. 



Figure 8. Effects of heavy rainfall on the channel water and intertidal 

 marsh soils of tidal estuaries and closed lagoons. 



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