ALBERT

Description: In order to reduce the level of risk associated with borehole drilling, it is important to have detailed knowledge about the aquifer distribution. In a view to generating groundwater potential model of Lokoja and its environs, the detailed subsurface characterization was carried out using a GIS-based multi-criteria decision analysis approach. One hundred and twenty-four vertical electrical sounding (VES) data points were covered within the study area using the Schlumberger array of electrical resistivity surveys. Hydrogeological investigation of one hundred and twenty-four existing boreholes within the vicinity of the sounded VES points was carried out by measuring in situ parameters of each borehole such as borehole depth, elevation, static water level and borehole yield. A Multi-Criteria Decision Analysis-Analytical Hierarchy Process (MCDA)-AHP-based was carried out by estimating the probabilistic ratings for the classes of parameters used for modeling groundwater potential. Four groundwater potential influencing factors, namely coefficient of anisotropy, transverse resistance, aquifer resistivity and aquifer thickness, were classified and rated. The output of the multi-criteria decision analysis was processed in the GIS environment to produce a groundwater potential index map. The obtained model was validated by comparing it with in situ borehole yield data to determine the accuracy of the proposed model. The groundwater potential map generated classified the study area into low, medium and high yield zones. Areas with medium potential zones dominate the largest part of the with 66% area coverage, and the dominance of these zones was visible in the northern and western part of the study area. Areas with high groundwater potential exist toward the southern and eastern sections of the study area. This area was observed to be underlined with sandstone, siltstone and migmatite. The validation exercise carried out on the proposed model reveals a 70% prediction accuracy.

Description: In this paper, the simulation–optimization method is used to study the optimal location of cutoff walls for seawater intrusion. The optimization model is based on minimizing the chlorine concentration of two water sources after 50 years. In order to reduce the computational complexity, a Kriging surrogate model simulation is coupled with the optimization model. Finally, a hypothetical case is used to evaluate the accuracy of the surrogate model and the performance of the optimization model. The results show that the outputs of the Kriging surrogate model and the variable density groundwater simulation model for the same cutoff wall design fit well, and the average relative error of the two outputs is only 2.2% which proves that it is feasible to apply the Kriging surrogate model to this problem. By solving the optimization model, the location of the cutoff wall which minimizes the sum of chlorine concentration of the two water sources after 50 years is obtained. This provides a stable and reliable method for the site selection of cutoff walls for future projects intended to prevent and control seawater intrusion.

Description: Heavy metals are very toxic and hazardous for human health. Onsite screening of heavy metal contaminated samples along with location-based automation data collection is a tedious job. Traditionally high-end equipment’s such as gas chromatography mass spectrometer (GC–MS) and atomic absorption spectrometers have been used to measure the concentration of different heavy metals in water samples but most of them are costly, bulky, and time consuming, and requires expert human intervention. This manuscript reports an ultra-portable, rapid, cost-effective, and easy-to-use solution for onsite heavy metal concentration measurement in drinking water samples. Presented solution combines off-the-shelf available chemical kits for heavy metal detection and developed spectrometer-based readout for concentration prediction, quality judgment, and automatic data collection. Two chemical kits for copper and iron detection have been imported form Merck and have been used for overall training and testing. The developed spectrometer has capability to work with smartphone-based android app and also can work in standalone mode. The developed spectrometer uses white light-emitting diode as a source and commercially imported spectral sensor (AS7262) for visible radiation reception. A low-power sub-GHZ-based wireless embedded platform has been developed and interfaced with source and detector. A power management module also has been designed to monitor the battery status and also to generate low battery indication. Overall modules has been packaged in custom designed enclosure to avoid external light interference. The developed system has been trained using standard buffer samples with known heavy metal concentrations and further tested for water samples collected from institute colony and nearby villages. The obtained results have been validated with commercially imported system from HANNA instruments, and it has been observed that developed system has shown excellent accuracy to predict heavy metal concentration (tested for Fe and Cu) in water samples.

Description: Many basins in the Cerrado biome already face increases in water disputes caused by agricultural expansion without long-term planning and monitoring of natural resources. The amount and timing of water availability are crucial for the socioeconomic development of agricultural activities and climate change resilience enhancement in the Cerrado. This study relied on a dataset developed for the Cerrado to characterize its climate and current water availability status. Different climate indices and hydrological signatures were adopted to describe the energy and water budget, climate seasonality, flow magnitude, flow dynamics, and average duration of low-flow events. Risk analysis was carried out to classify the monthly risk severity and identify periods and regions under a higher pressure regarding water availability in the Cerrado. Overall, the water availability is higher in the western and southern regions and lower in the eastern and northern regions, which experience a transition to a humid and semiarid climate, respectively. The water resources in the Cerrado occur under the highest pressure in September and October. We also identified regions with the potential to increase sustainable water use. These regions exhibit a low ratio between the flow equal to or exceeded 95% of the time and the mean flow (Q95/Q), which indicates that sustainable water use may be improved with techniques related to flow regularization and rainwater/runoff harvesting.

Description: Wastewater generated from different sources affects the health of living organisms and the natural environment due to the availability of different pollutants. Electrocoagulation (EC) is a good technology implemented for wastewater treatment before discharging to an environment as effluents. The electrocoagulation process is an effective method to the remove the color, chemical oxygen demand (COD), turbidity, and consumption of less energy from wastewater by considering different operating parameters. In this study, the major operating parameters for the electrocoagulation process such as pH (3–7.50), electric current (0.03–0.09 A), electrolytic concentration (1–3 g/L), the distance between electrodes (1–2 cm), electrolysis time (20–60 min) and combination of electrodes (Fe–Fe and Al–Al) were studied. The maximum removal of color–94.40%, COD–97.02%, and turbidity–90.91% with required energy consumption –36kWhr/m3 was obtained at the electric current–0.09 A, electrolyte concentration–3 g/L, pH–7, electrode combination–Fe–Fe, and distance between electrodes–3 cm, respectively. The studied parameters were affected the removal % color, % COD, % turbidity, and also the consumption of energy depending on the desired setup of fixed values of the parameter. Consumption of energy and electrode dissolution is related to the cost of operating in electrocoagulation in addition to the cost of labor and the small amount of sludge produced for disposal.

Description: The municipality of Santa Ignacia in the Province of Tarlac is highly dependent on groundwater as its major water supply for various purposes, but there is inconsistency in monitoring groundwater quality in the area which may impact the health of consumers. This study presented the preliminary assessment of groundwater quality through the application of spatial mapping. Out of 6,815 wells in the municipality, groundwater samples were collected from 274 hand pump wells. The measurements of selected groundwater quality parameters such as pH, conductivity, nitrate, nitrite, and iron of groundwater samples were determined on-site. The geographical coordinates of sampled wells and measurements of groundwater quality parameters were used in Geographic Information System software, QGIS, to construct the spatial distribution and spatial variation maps. The values of measured parameters were interpolated using the inverse distance weighted technique to predict the parameters at other sites in Santa Ignacia. Spatial variation maps revealed that the groundwater quality parameters varied in the municipality. All measured parameters, except the nitrite content, were within the acceptable limits set by the World Health Organization for drinking water. The high level of nitrite content in groundwater may be attributed to the application of fertilizers during agricultural activities. The nitrite content of groundwater, which exceeded the permissible limit, may cause long-term public health problems. Hence, an upscale evaluation and monitoring of groundwater quality and existing anthropological activities in the municipality are highly recommended. The identification of other possible source(s) of nitrite is necessary to lessen possible contamination risk and to protect the groundwater sources in the municipality. The results of this preliminary study would be useful in prospect studies of groundwater quality in the study area and in other provinces in the Philippines.

Description: Decentralized wastewater plants have been proven to be cost-effective, easy to construct and operate and widely used in small ruler communities. The suitability of reclaimed wastewater for irrigation purpose was evaluated in this study based on the various water quality parameters, international water quality standards and water–irrigation water quality guideline (JS 1766). Twenty-seven samples were collected from a decentralized wastewater plant that is located in Balqa Governorate in Salt city, Jordan. Samples were analyzed for pH, electrical conductivity, major anions and cations, as well as biological oxygen demand, chemical oxygen demand and total suspended solids. Study results show that water is slightly alkaline in nature. According to Jordanian domestic reclaimed wastewater standard, the use of water for irrigation has a mild-to-moderate degree of restriction. Using the US Salinity Laboratory classification scheme, there is high salinity and medium sodium water, 50% of samples falls in the area of (C3-S2) and this water is suitable for irrigation for many types of soil with low risk of increasing exchangeable sodium content. According to chloride hazards, the water for irrigation can be used for moderately tolerant plants. 74% of the samples have the residual sodium carbonate (RSC) less than 1.25 meq/L and hence suitable for irrigation. The study recommends that treated wastewater from decentralized wastewater a plant is considered as non-conventional source for irrigation.

Description: The facile synthesis of graphene wool doped with oleylamine-capped silver nanoparticles (GW-αAgNP) was achieved in this study. The effect of concentration, pH, temperature and natural organic matter (NOM) on the adsorption of a human carcinogen (benzo(a)pyrene, BaP) was evaluated using the doped graphene wool adsorbent. Furthermore, the antibacterial potential of GW-αAgNP against selected drug-resistant Gram-negative and Gram-positive bacteria strains was evaluated. Isotherm data revealed that adsorption of BaP by GW-αAgNP was best described by a multilayer adsorption mechanism predicted by Freundlich model with least ERRSQ 

Description: Given the aesthetic, cultural, ecological, and economic value of the date agro-system in Southwestern Tunisia, different management and conservation strategies have been warrantee to optimize land productivity sustainably. However, the inefficiency of the adopted management actions resulted in a continuous loss of soil fertility and decreasing fruit quality. Thus, the present paper attempts to evaluate accurately the evolution of the principal factors influencing date palm production and agricultural activities sustainability in the region. Integrated approaches of various irrigation water quality indices and geostatistical analysis coupled with field investigation and farming survey were applied to evaluate the evolution of key parameters influencing the development of date palm sustainably. The obtained results of the research indicate that the progressive land degradation is due to the effects of poorquality of water used for irrigation (EC between 674.4 and 5450 µs/cm, SAR exceeding locally 20 and about 80% of all the samples waters are of undoubtful quality according to the calculated indices), inappropriate irrigation scheduling (physiologic drought that might reach 3 months), traditional basin irrigation technique (decreasing of yield productivity, locally of 0.23, 0.23 and 0.25 kg m−3), an indigenous knowledge (sandy amendment, biologic compost, gravity improved irrigation…..). Also climate variability has leaded to furthermore degradation of crop quality. The degradation of date palm culture will be a great challenge for environmental conservation, food security and socio-economic values of the region unless a reasonable management take place, a flexible strategy based on indigenous knowledge of landowner, and scientific-based outlines with climate risks evaluation. The present paper might be useful to policy makers as a multi-disciplinary research covering most of the important aspects of date palm production.

Description: This study evaluates the impact of climate change (CC) on runoff and hydrological drought trends in the Hablehroud river basin in central Iran. We used a daily time series of minimum temperature (Tmin), maximum temperature (Tmax), and precipitation (PCP) for the baseline period (1982–2005) analysis. For future projections, we used the output of 23 CMIP5 GCMs and two scenarios, RCP 4.5 and RCP 8.5; then, PCP, Tmin, and Tmax were projected in the future period (2025–2048). The GCMs were weighed based on the K-nearest neighbors algorithm. The results indicated a rising temperature in all months and increasing PCP in most months throughout the Hablehroud river basin's areas for the future period. The highest increase in the Tmin and Tmax in the south of the river basin under the RCP 8.5 scenario, respectively, was 1.87 °C and 1.80 °C. Furthermore, the highest reduction in the PCP was 54.88% in August under the RCP 4.5 scenario. The river flow was simulated by the IHACRES rainfall-runoff model. The annual runoff under the scenarios RCP 4.5 and RCP 8.5 declined by 11.44% and 13.13%, respectively. The basin runoff had a downward trend at the baseline period; however, it will have a downward trend in the RCP 4.5 scenario and an upward trend in the RCP 8.5 scenario for the future period. This study also analyzed drought by calculating the streamflow drought index for different time scales. Overall, the Hablehroud river basin will face short-term and medium-term hydrological drought in the future period.