Influence of rainfall on the discharge, nutrient concentrations and
loads of a stream of the “Pampa Ondulada”
Our findings show that disseminated seepage of nutrient-rich mostly saline groundwater into the Upper Gulf of
Thailand is significant. Estimated fluxes of dissolved inorganic nitrogen (DIN) supplied via groundwater discharge were
40–50% of that delivered by the Chao Phraya River, inorganic phosphate was 60–70%, and silica was 15–40%. Dissolved
organic nitrogen (DON) and phosphorus (DOP) groundwater fluxes were also high at 30–40% and 30–130% of the river
inputs, respectively. These observations are especially impressive since the comparison is being made to the river that is the largest source of fresh water into the Gulf of Thailand and flows directly through the megacity of Bangkok with high
nutrient loadings from industrial and domestic sources.