Author(s): Sinxay Vongphachanh, William Milne-Home, Ashim Das Gupta, James E. Ball
Linked Author(s): Vongphachanh Sinxay
Keywords: Sukhuma District, seasonal groundwater level fluctuation, correlation, GLDAS, GRACE
Abstract: The objective of this study is to investigate the seasonal fluctuation of groundwater level in Sukhuma District by using observed data on groundwater, rainfall and streamflow from June 2015 to May 2016 and remote sensing data derived from the Gravity Recovery and Climate Experiment (GRACE) and the Global Land Data Assimilation System (GLDAS) for the period of June 2015 to March 2016. The results show that the groundwater level in Sukhuma District increased to the peak elevation during the late wet season (September � October) and it started declining from November until reached the lowest elevation during the late dry season (April � May). Rainfall was found at a significant (P<0. 01) factor influencing the groundwater level fluctuation. The delay time between rainfall and groundwater level rise was also estimated at about 4 weeks. Moreover, the results also show that groundwater level during the study period in Sukhuma District was not yet depleted. However, the time-series for this analysis is very short to investigate the trend of groundwater level in Sukhuma District. The results of this research also showed good correlation between the soil moisture from GLDAS and groundwater level measurement in Sukhuma District (R2 = 0. 91) and also showed a good agreement between the soil moisture from GLDAS at a GRACE footprint and the equivalent water height (EWH) derived from GRACE at a GRACE footprint with an R2 value of 0. 72. Therefore, regarding the results of this study, a further investigation using these remote sensing data for groundwater study in this region will be carried out to support in groundwater study for Sukhuma and Southern Laos. The products from GRACE and GLDAS will provide pivotal data for the study of hydrogeology in the areas with limited field observation data
Year: 2017