Groundwater Recharge Estimation in Sukhuma District, Champasak Province, Southern Laos: A Preliminary Assessment

Southern Laos is undergoing economic and agricultural development, resulting in a large increase in groundwater and surface water use. However, these water resources are not known in detail. This study aims to investigate the groundwater and surface water interactions in the Sukhuma District of Champasak Province using a network of sixteen rain gauges and groundwater levels measurement points. Groundwater levels are measured weekly in eleven domestic wells, which are pumped irregularly, and also in five observation bores. Aquifer recharge occurs from direct infiltration of rainfall and also is derived using baseflow calculated from daily streamflow measurements at the re-established gauging station on the Khamouan River in Sukhuma District. The Khamouan River is connected to the groundwater in its lower reaches in both dry and wet seasons. Baseflow proportion to the total streamflow in the wet season 2015 has been estimated at 46%. The distribution of direct recharge has been mapped with ArcGIS and is spatially variable. Preliminary estimates of rainfall recharge have been calculated by the water table fluctuation method for 2015 but show a high degree of uncertainty related to the specific yield estimates. Time series analysis has confirmed the observed lag of some three to four weeks between the wet season start and rise in groundwater levels. These preliminary results indicate that there is close interaction between groundwater and surface water in the Sukhuma District. Further analysis will refine these results and extend them through remote sensing across southern Laos for application to integrated water resources management

Police interview of suspects in China: developments and analyses

This paper investigates the power dynamics in police interviews with suspects in China by examining a real-life sample. It first overviews some recent developments and legislation in China regarding police interviewing of suspects, followed by outlining the linguistic and psychological research which the analyses are based upon. The interviews are examined using critical discourse analysis that reveals the high-power position of the Chinese police in suspect interviews. However, the large proportion of open questions found in the interviews is encouraging, as this suggests that the regulations outlawing use of evidence obtained by torture or other illegal means is taking effect. This paper is the very first to empirically examine actual Chinese police interviews with suspects, providing valuable insights for theories and practice.N/

Interview and interrogation methods and their effects on true and false confessions

The interviewing and interrogation of suspects can be particularly important to securing convictions against the guilty and freeing the wrongly accused. There are two general methods of questioning suspects: information-gathering and accusatorial. The information-gathering approach, used in the United Kingdom, New Zealand, Australia, and elsewhere, as more generally in Western Europe, is characterized by rapport-building, truth-seeking, and active listening. The accusatorial approach, used primarily in the United States and Canada, is characterized by accusation, confrontation, psychological manipulation, and the disallowing of denials. Which method is more effective has become a hotly debated topic as the number of false confessions identified continues to rise. Our objective was to systematically and comprehensively review published and non-published, experimental and observational studies on the effectiveness of interviewing and interrogation methods. We focus on the questioning of suspects using information-gathering and accusatorial methods seeking to elicit confessions

Applicability of geochemical techniques and artificial sweeteners in discriminating the anthropogenic sources of chloride in shallow groundwater north of Toronto, Canada

© 2017, Springer International Publishing Switzerland. Elevated levels of chloride concentration due to anthropogenic activities including the road salts, septic effluent and agricultural sources are common in shallow groundwater of the recent glacial deposits north of Toronto, Ontario, Canada. Identifying suitable techniques for discriminating the source of the chloride concentration helps to better plan the protection of groundwater in the area. This paper examines the applicability of geochemical techniques with emphasis on Panno et al. (Ground Water 44: 176–187, 2006) and Mullaney et al. (2009) graphical approaches for discriminating the sources of chloride with known causes of impacts. The results indicated that the graphical methods developed using Cl−, Br− and/or total nitrogen (N) could identify the combined sources of road salts and septic systems. However, discriminating between the road salts, septic effluent or agricultural sources needs to be complemented by other techniques including the artificial sweeteners and isotope tracers

Water infrastructure and the environment conference, 28 Nov – 2 Dec 2016, millennium hotel, queenstown, New Zealand groundwater recharge estimation in sukhuma district, champasak province, southern Laos: A preliminary assessment

© 2017 Engineers Australia. All Rights Reserved. Southern Laos is undergoing economic and agricultural development, resulting in a large increase in groundwater and surface water use. However, these water resources are not known in detail. This study aims to investigate the groundwater and surface water interactions in the Sukhuma District of Champasak Province using a network of sixteen rain gauges and groundwater levels measurement points. Groundwater levels are measured weekly in eleven domestic wells, which are pumped irregularly, and also in five observation bores. Aquifer recharge occurs from direct infiltration of rainfall and also is derived using baseflow calculated from daily streamflow measurements at the re-established gauging station on the Khamouan River in Sukhuma District. The Khamouan River is connected to the groundwater in its lower reaches in both dry and wet seasons. Baseflow proportion to the total streamflow in the wet season 2015 has been estimated at 46%. The distribution of direct recharge has been mapped with ArcGIS and is spatially variable. Preliminary estimates of rainfall recharge have been calculated by the water table fluctuation method for 2015 but show a high degree of uncertainty related to the specific yield estimates. Time series analysis has confirmed the observed lag of some three to four weeks between the wet season start and rise in groundwater levels. These preliminary results indicate that there is close interaction between groundwater and surface water in the Sukhuma District. Further analysis will refine these results and extend them through remote sensing across southern Laos for application to integrated water resources management

Landfill site characterisation at Kham Bon village, Muang district, Khon Kaen province, NE Thailand

The aim of the study is to characterise the Kham Bon landfill site. Hydrogeological and geochemical surveys were conducted and four boreholes were drilled. The hydraulic properties of the aquifer were tested, and soil, surface water and groundwater samples were collected at various times in the year. The physical and chemical properties of the samples, especially heavy metals, were analysed. The results indicated that Cd, Cr, Pb, Cu and Zn occurred in significant concentrations in the soil. The concentrations of Pb, Fe and Mn are high in surface water and groundwater. Moreover, the groundwater chemistry of the shallow aquifer was characterised by high concentrations of some ions. The major factors controlling leachate production and migration in this area are the seasonal variations in precipitation, the site topography, which controls the runoff patterns, and the soil type, which affects infiltration and solute transport to the water table. Copyright © 2009, Inderscience Publishers

Seasonal Groundwater Level Fluctuations In Sukhuma District Of Southern Laos

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

Estimation of soil infiltration and groundwater recharge in Sukhuma district of southern Laos

© Proceeding of the 21st LAHR-APD Congress 2018. All rights reserved. This study is presented to estimate net soil infiltration and groundwater recharge in Sukhuma District of Southern Laos. A soil water balance approach is used to estimate the net infiltration from the Tropical Rainfall Measuring Mission (TRMM) and Global Land Data Assimilation System (GLDAS) data. The groundwater recharge is estimated by using the water table fluctuation method from observation groundwater levels at eleven domestic wells and five paired observation wells (shallow and deep). The results show that average annual net infiltration flux from 2000-01 to 2015-16 is decreasing at a rate of 6 mm/year. For the same period of the net infiltration flux, the average annual rainfall derived from TRMM for the Sukhuma District also depicts a declining trend with a rate of 26 mm/year. A value of specific yield for the shallow fractured sandstone aquifer in the Sukhuma District is quantified at approximately 0.03. Groundwater recharge for 2012-13 and 2015-16 is estimated at 5% (118 mm) and 4% (95 mm) of annual rainfall, respectively. The net infiltration estimated from GLDAS and TRMM data shows reasonable agreement with the ground-based measurements. The results of the current study provide useful basic information for future groundwater resource management planning in Sukhuma District. The methods applied in this study may be also useful for studying the soil infiltration and groundwater recharge in regions with limited field data