Keywords

sea level rise, salinity, acidity, coastal, Mekong River Delta, modelling

Location

Session H5: Systems Modeling and Climate Change: A Systematic Methodology for Disentangling Elements of Vulnerability, Adaptation and Adaptive Capacity

Start Date

16-6-2014 3:40 PM

End Date

16-6-2014 5:20 PM

Abstract

Bac Lieu is a coastal province in the Mekong River Delta (MRD), Vietnam. Aside from salinity intrusion from the sea, the province is strongly affected by acidic pollution as 58% of the area (250,000 ha) is overlaid with acid sulphate soil (ASS). Previous studies showed that the eminent sea level rise (SLR) would influence the hydrology and salinity of the canal networks in the province. This study, using the previously validated hydraulic and water quality model CRSAP-ACIDITY (Vietnam River Systems And Plains, coupled with ACIDITY Module), aimed at quantifying impacts of different SLR scenarios (SLR=17, 30, 50, or 75 cm) on acidic pollution in the province. Under the present sea level, widespread acidic pollution (pH < 5) of surface water occurred at the start of the rainy season, due to leaching of acidity from canal embankments and fields in ASS. The acceleration of SLR reduced the area of acidic pollution water. The lessening in acidic pollution was attributed to (1) SLR that raised the water level in the Mekong River, increasing the amount of fresh water flowing into the study area; and (2) the amount of water drained out of the study area increased, bringing with it acidity. It concluded that SLR has a positive effect on acidic pollution in the ASS coastal area.

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Jun 16th, 3:40 PM Jun 16th, 5:20 PM

Sea level rise effects on acidic pollution in a coastal acid sulphate soil area

Session H5: Systems Modeling and Climate Change: A Systematic Methodology for Disentangling Elements of Vulnerability, Adaptation and Adaptive Capacity

Bac Lieu is a coastal province in the Mekong River Delta (MRD), Vietnam. Aside from salinity intrusion from the sea, the province is strongly affected by acidic pollution as 58% of the area (250,000 ha) is overlaid with acid sulphate soil (ASS). Previous studies showed that the eminent sea level rise (SLR) would influence the hydrology and salinity of the canal networks in the province. This study, using the previously validated hydraulic and water quality model CRSAP-ACIDITY (Vietnam River Systems And Plains, coupled with ACIDITY Module), aimed at quantifying impacts of different SLR scenarios (SLR=17, 30, 50, or 75 cm) on acidic pollution in the province. Under the present sea level, widespread acidic pollution (pH < 5) of surface water occurred at the start of the rainy season, due to leaching of acidity from canal embankments and fields in ASS. The acceleration of SLR reduced the area of acidic pollution water. The lessening in acidic pollution was attributed to (1) SLR that raised the water level in the Mekong River, increasing the amount of fresh water flowing into the study area; and (2) the amount of water drained out of the study area increased, bringing with it acidity. It concluded that SLR has a positive effect on acidic pollution in the ASS coastal area.