Primary Water Source Research Articles

Assessment of vulnerability and hydrogeochemical specifications of Bahabad Yazd Plain aquifer.

Available quality groundwater resources are declining globally due to population growth, agricultural activities, industrialization, and urbanization. Wells in Bahabad Plain, located in Yazd Province, Iran, are the primary source of water demanded by humans for drinking and agricultural activities. Hence, it is pivotal to examine the quality of groundwater resources, which is the main objective of this study. To this end, seventeen water samples collected in the region were using standard sampling methods, and ten parameters were examined from the samples, namely pH, TH, TDS, SO4, HCO3, Cl-, K+, Ca+, Mg+, and Na+. Water quality index (WQI) was used to determine water quality, and SI, GODS, and DRASTIC methods were used to examine aquifer vulnerability to contamination. Schoeller's diagram indicated that 11% of the samples were at an excellent level; 33% were at a drinkable level; 20% were at a not-suitable level for drinking; 26% were terrible for drinking; and 10% were at an almost non-drinkable level. According to WQI results, 23.53% of the samples had no limitation for drinking, 35.29 were of low quality, 17.65% were of inferior quality, and 23.53% were non-drinkable. The GODS method results indicated that the eastern, central, western, and small parts sporadically scattered in northern regions of the study area (39.93%) had a moderate vulnerability. Lastly, a significant portion of the northern and southern districts (60.07%) was found to have a low vulnerability to contamination, which was in line with WQI results.

DESIGNING THE ROLE OF SETTLEMENTS IN URBAN AREAS TO INCREASE GROUNDWATER CONSERVATION EFFORTS

This article is based on research results that state that floods and droughts occur almost every year in many places in the biosphere. It happens because there is no proper water management. Rainwater is the primary water source in life; the balance between discharge and income (recharge) is not controlled. In this article, we try to manage rainwater by inviting the whole community with yard media, where every person in the world takes refuge in the yard. Data is taken from yards in the settlement of Surabaya, as a large city on the coast located in the lowlands, densely populated (100 inhabitants / Ha), prone to flooding and intrusion of seawater. They determined the size of the yard most inhabited by most people of Surabaya, namely the size of the land < 300m2, studied 40 yards as samples. The variables studied were: the land area of the yard, the site of the building, the canopy area of the trees, the size of ornamental plant headers, the scope of grass, the location of the open section, and the percentage of coarse grains (these six variables as predictors), rainfall (determined by intensity as a standard count), and runoff of water that comes out of the yard (as criterium). Results of analysis with multiple regressions; Successive yard variables are the area of the building, the location of grass, the site of open land, the scope of the tree canopy, gauze grains above the ground, and lastly, the area of ornamental plants. The six variables contributed to the surface runoff of 61.1%; thus, planning yard patterns in the city of Surabaya or other cities should pay attention to the role of these variables.

GIS-Based Surface Runoff Modeling Using Empirical Technique For A River Basin In South India

Precipitation is the primary source of fresh water in the world. Surface runoff will happen when the amount of rainfall is greater than the soil’s infiltration capacity. In most water resource applications, runoff is the most important hydrological variable. Aside from these rainfall characteristics, there are a number of catchment-specific elements that have a direct impact on runoff amount and volume. This research focuses on estimating surface runoff over the lower Vellar basin, a river basin in the southern part of India, by integrating Soil Conservation Service-Curve Number (SCS-CN) method with GIS. This technique is one of the most common methods used by hydrologists for estimating surface runoff. Curve Number (CN) is an index established by the Natural Resource Conservation Service (NRCS) to denote the potential for stormwater runoff. The nature of the watershed is explored first by creating land use and land cover pattern followed by the preparation of slope, drainage, and location maps. The area taken for this study is the lower Vellar basin situated in the Cuddalore District of Tamil Nadu, India. The curve number is analyzed using the rainfall data of 15 years (2001-2015) and the runoff is being calculated. The watershed pattern of the study area is also explored being analyzed and executed. Preservation of the runoff water is also discussed.

Modeling and assessing water and nutrient balances in a tile-drained agricultural watershed in the U.S. Corn Belt

Identifying the key processes and primary sources of water and nutrient losses is essential for water quantity and quality management in watersheds. This is especially true in the U.S. Corn Belt, which has been recognized as the primary region contributing nutrient loads to the Great Lakes and the Gulf of Mexico. A SWAT (Soil and Water Assessment Tool) model simulation was set up in an agricultural watershed with about 50% tile drainage area in the U.S. Corn Belt to study the water and nutrient balance components for the whole watershed and the corn-soybean rotation system. The SWAT model was improved to consider additional nitrogen and phosphorus loss paths from the soil. The model was comprehensively calibrated and validated for simulating monthly stream flow, total suspended solids (TSS), nutrient loads (including total Kjeldahl nitrogen (TKN), nitrate and nitrite nitrogen (NOx-N), total phosphorus (TP) and orthophosphate phosphorus (orthoP)), actual evapotranspiration (ETa), leaf area index (LAI) and annual crop yields in the watershed from 2011 to 2019. Results showed the model performance was very good for simulating the stream flow, TSS and ETa, and acceptable for nutrient loads, LAI and crop yields. ETa, surface runoff, lateral soil flow, tile drainage and percolation respectively accounted for 65%, 15%, 2%, 8% and 9% of the precipitation. Fertilizer was the main source of nitrogen and phosphorus input to the watershed, and harvested crops were the main paths removing nutrients. Surface runoff, tile drainage and percolation each contributed about 30% of total nitrogen losses to water, with surface runoff being dominated by organic nitrogen while tile drainage and percolation were dominated by nitrate nitrogen. Phosphorus losses were mainly through surface runoff, which resulted in 66% of the total losses and was dominated by organic phosphorus and soluble phosphorus. Representing about 49% of the watershed area, the corn-soybean rotation system contributed 83% and 88% of the total nitrogen and phosphorus inputs, respectively, to the watershed, as well as 64% and 46% of the nitrogen and phosphorus losses to the water system, respectively. The non-growing season (October to the next April) was identified as the critical period resulting in water and nutrient losses due to low evapotranspiration and plant uptake. Targeted management strategies for reducing nutrient loads in key hydrological paths were suggested.

Investigating Bacterial and Free-Living Protozoa Diversity in Biofilms of Hot Water Pipes of Apartment Buildings in the City of Riga (Latvia)

Background: Biofilms, when formed on the surfaces of water pipes, can be responsible for a wide range of water quality and operational problems. We sought to assess the bacterial and free-living protozoa (FLP) diversity, in relation to the presence of Legionnaire's disease-causing bacteria Legionella pneumophila (L. pneumophila) in 45 biofilms of hot water distribution system pipes of apartment buildings in Riga, the capital city of Latvia.Results: 16S rRNA amplicon sequencing (metataxonomics) revealed that each biofilm contained 224 rather evenly distributed bacterial genera and that most common and most abundant were two genera, completely opposites in terms of their oxygen requirements: the obligately anaerobic Thermodesulfovibrio and the strictly aerobic Phenylobacterium. Water temperature and north-south axis (i.e., different primary water sources) displayed the most significant effect on the inter-sample variations, allowing us to re-construct three sub-networks (modules) of co-occurring genera, one involving (potentially FLP-derived) Legionella spp. Pangenome-based functional profile predictions suggested that all three may be dominated by pathways related to the development and maintenance of biofilms, including quorum sensing and nutrient transport, as well as the utilization of various energy sources, such as carbon and nitrogen. In our 18S rRNA amplicon sequencing data, potential hosts of L. pneumophila were detected in 11 out of 12 biofilm samples analyzed, however, in many cases, their relative abundance was very low (<1%). By validating our findings using culture-based methods, we detected L. pneumophila (serogroups 2, 3, 6 and 9) in nine (20%) biofilms, whereas FLP (mostly Acanthamoeba, Vahlkampfidae and Vermamoeba spp.) were present in six (~13%) biofilms. In two biofilms, L. pneumophila and its potential hosts were detected simultaneously, using culture-based methods.Conclusions: Overall, our study sheds light on the community diversity of hot water biofilms and predicts how several environmental factors, such as water temperature and source might shape it.

ENVIRONMENTAL PROPERTIES AND ANALYSIS OF THE EUPHRATES RIVER WITHIN ANBAR GOVERNORATE IN IRAQ: A REVIEW

Euphrates River is the primary source of water in Anbar province. It provides the cities that passed with drinking, agricultural and industrial water, in addition to being the downstream of sewage and wastewater after treatment. Anbar province, and consequently the water of the Euphrates River, has been affected by climate and environmental changes resulting from the military operations, which have become an obsession for citizens and decision-makers in the province. This obsession became the motivation for conducting the necessary physical, chemical and biological measurements to identify the environmental characteristics of the Euphrates river due to the presence of many sources of pollution of rivers water and for the purpose of making sure that it is suitable for human uses, since its effects will be serious and direct on humans and the environment. The review article includes a comprehensive study of water quality in Anbar province, as well as a review of previous researches in this field to know and to improve the future of water in the province. As the specialists unanimously agreed that, the future crisis in the region is a water crisis. Also, the review included an analysis of physical, chemical, and biological measurements, and a comparison of results with Iraqi and international standard limits was made. Data were organized and the results were analyzed. Results were of importance, and important environmental recommendations were reached regarding Euphrates river within its flow stream and the time effect on it.

Water sources and kidney function: investigating chronic kidney disease of unknown etiology in a prospective study

A chronic Kidney Disease of unknown etiology (CKDu) has emerged with disproportionately high prevalence across dry lowland agricultural communities globally. Here we present the results of a prospective cohort of 293 patients with CKDu in the endemic region of Wilgamuwa, Sri Lanka, in whom we measured baseline kidney function and undertook quarterly follow up over 2 years. Well water was the primary historic drinking water source in the region, although a majority (68%) of participants reported switching to reverse osmosis water during study follow ups. Participants who reported ever drinking from well water had estimated glomerular filtration rates −6.7 (SD: 2.8) ml/min/1.73 m2 lower than participants who did not drink from well water historically (p = 0.0184) during the study period. Geospatial analysis identifies a cluster within the region where CKDu progression is significantly higher than the surrounding area. Samples of household wells (n = 262) indicated 68% had detectable agrochemical compounds with concentration above global water quality standards. It is expected that the detected contaminants compounds are indicators of poor water quality and that there is likely additional agrochemical exposure including commercial additives that may contribute to CKDu onset and/or progression. Thus, our study finds that well water exposure during a person’s lifetime in this region is associated with kidney function decline and identifies and quantifies putative nephrotoxic agrochemicals above safe drinking water concentrations in these wells.

Spatiotemporal monsoon characteristics and maize yields in West Africa

To assess the vulnerability of rainfed agriculture in West Africa (WA) to climate change, a detailed understanding of the relationship between food crop yields and seasonal rainfall characteristics is required. The highly seasonal rainfall in the region is expected to change characteristics such as seasonal timing, duration, intensity, and intermittency. The food crop yield response to changes in these characteristics needs greater understanding. We follow a data-driven approach based on historical yield and climate data. Such an approach complements model-based approaches. Previous data-driven studies use spatially and temporally averaged precipitation measures, which do not describe the high degree of spatial and temporal variability of the West African Monsoon (WAM), the primary source of water for agriculture in the region. This has led previous studies to find small or insignificant dependence of crop yields on precipitation amount. Here, we develop metrics that characterize important temporal features and variability in growing season precipitation, including total precipitation, onset and duration of the WAM, and number of non-precipitating days. For each temporal precipitation metric, we apply several unique spatial aggregation functions that allow us to assess how different patterns of high-resolution spatial variability are related to country-level maize yields. We develop correlation analyses between spatiotemporal precipitation metrics and detrended country-level maize yields based on findings that non-climatic factors, such as agricultural policy reform and increased investment, have driven the region’s long-term increase in maize yields. Results show that that the variability in the number of days without rain during the monsoon season and the lower bounds to the spatial rain pattern and end to the monsoon season are most strongly associated with maize yields. Our findings highlight the importance of considering spatial and temporal variability in precipitation when evaluating impacts on crop yields, providing a possible explanation for weak connections found in previous studies.

Co-Existence of Free-Living Amoebae and Potential Human Pathogenic Bacteria Isolated from Rural Household Water Storage Containers.

Simple SummaryIn many households in rural communities, water needed for drinking and cooking is fetched from rivers, fountains, or boreholes shared by the community. The water is then stored in various storage containers for several days without treatment and exposed to several conditions that could potentially contaminate the water and cause diseases. If the storage containers are not regularly and properly cleaned, biofilms can form inside the containers. Several microorganisms can be found inside the biofilm that can potentially cause diseases in humans. One such group of organisms is called free-living amoebae, which graze on the bacteria found inside the biofilm. Several of these potentially harmful bacteria have adapted and can survive inside these free-living amoebae and potentially cause diseases when ingested by humans.This study investigated the co-existence of potential human pathogenic bacteria and free-living amoebae in samples collected from stored water in rural households in South Africa using borehole water as a primary water source. Over a period of 5 months, a total of 398 stored water and 392 biofilm samples were collected and assessed. Free-living amoebae were identified microscopically in 92.0% of the water samples and 89.8% of the biofilm samples. A further molecular identification using 18S rRNA sequencing identified Vermamoeba vermiformis, Entamoeba spp., Stenamoeba spp., Flamella spp., and Acanthamoeba spp. including Acanthamoeba genotype T4, which is known to be potentially harmful to humans. Targeted potential pathogenic bacteria were isolated from the water samples using standard culture methods and identified using 16S rRNA sequencing. Mycobacterium spp., Pseudomonas spp., Enterobacter spp., and other emerging opportunistic pathogens such as Stenotrophomonas maltophilia were identified. The results showed the importance of further studies to assess the health risk of free-living amoebae and potential human pathogenic bacteria to people living in rural communities who have no other option than to store water in their homes due to water shortages.

Climate Change and Public Health in the Oromia Regional State in Ethiopia and Its Implications for the Nile Basin

Background: Climate change in the Nile Basin region has caused complex ecological imbalances, i.e., increased diseases burdens, widened social inequalities, exacerbated environmental degradation, fostered competition on resources, and threatened to slash progress in population health. In addition, human rights violations (HRV) in Oromia resulted in further environmental degradation. In this paper, the term healthy social relations and respect for human rights are used interchangeably. Oromia is the primary water source for the Nile River; hence, any social problem and ecological imbalances in this region easily spill over an extended area. Objectives: This paper examines the relationships between climate change, HRV, and public health. It traces the mechanisms in which the interactions may multiply public health problems, raise awareness of the issues, advance cooperation between states to undertake applied research, foster environmental stewardship culture, and provide impactful policy directions. Methods: Using the systemic thinking framework, we captured tacit and scientific knowledge at the upstream level in Oromia, analyzed the complex relationships between climate change, HRV, and public health problems. Furthermore, we depicted the risks it poses in Oromia and Nile Basin's downstream countries. Findings: Climate change and HRV exacerbated environmental degradation, widened social problems, and inculpated drawbacks in public health status. The impacts of ecological disturbances in the Oromia region easily spill over to other Nile Basin countries. Environmental and social imbalances contribute to environmental degradation through increased soil erosion, deforestation, increased water evaporation, which may also cause decreased water flow to the tributary rivers of the Nile. Climate change could also alter the biochemistry and microbiology of the water and soil, creating favorable conditions for certain microorganisms and pathogens that may lower soil fertility, food production, aggravate water scarcity, and ultimately cause food insecurity and other scarcities. Conclusions: Climate change and HRV in Oromia aggravated environmental degradations and have implications for public health problems. Moreover, the social and ecological disturbances in Oromia easily spill over to other Nile Basin countries. Until we identify what is going on in Oromia and take appropriate actions to prevent, mitigate and manage the impacts of climate change, and advance human rights, public health problems will further multiply and threaten the security of people in Oromia and other regions within the Nile Basin.

Inter-Decadal Dynamics of Glacier Area and Supra-glacial Lakes Over Hispar Glacier, Western Karakoram

Glaciers of the central Karakorum region are the primary source of fresh water and lifeline for downstream inhabitants but changing climatic conditions put serious impacts on glaciers which cause rapid ablation and the creation of glacial lakes. Many natural hazards are associated with glaciers and glacial lakes like Glacier lake outburst flood (GLOF). Using Geographic Information System and Remote sensing techniques on Hispar glacier which is part of central Karakorum, the current study applied Landsat (TM, ETM, ETM+, and OLI) and sentinel-2 satellite imagery. Further, mapping to the Hispar glacier is done to know the variations in glacier and supraglacial lakes between 1990 and 2019. According to the results, about 90% of glacial ponds are present in the debris-covered area while only 10% are present in the clean ice and scow area. This study identifies the decreasing trend in the number and the area of glacial lakes. In 1990, about 42 glacial ponds were covering a total area of 0.733km2, whereas, in 2019, 20 glacial lakes were covering an area of 0.18km2. In the last three decades (1990-2019) about 20km2 of clean ice and snow is increased. The findings of climate data revealed that there is a decreasing trend of temperature and an increasing trend of precipitation. Since 1995, about 0.75oC temperature is observed in HRB. The findings of this study somehow support the Karakoram anomaly.

Epikarst shallow fissure soil systems are key to eliminating karst drought limitations in the karst rocky desertification area of SW China

AbstractSurface soil water shortages are among the primary factors limiting revegetation in most degraded regions with shallow soil, especially in karst areas. Finding water sources for plants is an urgent task to ensure maximum vegetation restoration in these areas. We combined soil water content monitoring and isotope tracing to reveal the principal water source supply systems for plants in karst areas. The results showed that the content and storage of water in the shallow fissure soil system (SFSS) of the epikarst zone were consistently higher and more temporally stable than that of the surface soil. Thus, epikarsts with dissolution voids and fissures are important, stable aquifers that provide water to plants. Moreover, the IsoSource results showed that the SFSS was the primary water source for three monitored tree species (Cupressus torulosa D. Don, Pyracantha fortuneana [Maxim.] Li and Rosa cymosa Tratt.), especially C. torulosa and P. fortuneana. The water‐uptake patterns of C. torulosa and P. fortuneana changed from dominant SFSS and surface soil water sources during the rainy period to the dominant SFSS and transfer zone (TZ) of vadose zone water sources during the dry period. In contrast, Rhynchospora cymosa uses water from SFSS and TZ water sources only during drought. These results suggest that the SFSS is key to eliminating vegetation restoration limitations due to surface drought in karst areas. It is proposed that deeply rooted plants with dimorphic root systems are optimal for sustainable vegetation restoration in karst areas.

The potential of river discharge at the peak of the dry season in some disaster-prone area of Merapi Volcano

With a high level of volcanic activity and many people living in the disaster-prone area, sustainable disaster management in the Merapi Volcano area is still very much needed in the future. One of the needs in building disaster management is ensuring water resources available during the pre-eruption period. So far, springs are the primary source of water that has been widely used by residents in the volcanic foothills, which are prone to eruption disasters. However, at the time of the eruption, many springs were not functioning so that alternative water sources were needed. River water can be an alternative water source, and a study of river water's potential is required to ensure its feasibility. This study was conducted on the south to the southwest side of Merapi Volcano to analyze the quantity and quality of river water as an alternative water source. Data collected through observation, literature study, and document search. Data analysis performed using descriptive analysis, matching analysis, and statistical analysis using independent sample t-test and simple linear regression. The study results show that seven rivers in the south to the southwest slope can be used as water sources because they are not lava flows. These rivers have varying discharge and water quality. There is no difference in discharge and water quality between the top and the bottom of the volcano foot. When dry season is on the peak, three rivers have no flow because some springs locations are at the volcano's bottom. Overall, based on these findings, it can be emphasized that the use of water sources is needed to do at the closest point to the evacuation barracks. However, a water treatment installation needs to be provided in the evacuation barracks so that the river water is suitable for consumption.

Analysis of groundwater quality in Cimahi City of West Java Province

Cimahi City is currently experiencing a clean water crisis, the cause of which is increasing population growth, so that water needs increase and land conversion, which results in reduced groundwater infiltration. The primary source of clean water in this city is groundwater. Population growth and residential development have an impact on pollution originating from domestic waste. These two things cause the quality and quantity of groundwater in Cimahi City to be increasingly critical. This study aims to analyze the quality of groundwater used by residents of Cimahi City. The data used is secondary data from the Environmental Service in 2019. Sampling was carried out at thirty points in Cimahi City spread over 14 urban villages, namely Citereup, Pasir Kaliki, Cibereum, Cibabat, Cipageran, Cimahi, Leuwigajah, Setiamanah, Karang Mekar, Cibeber, Melong, Cigugur, Padasuka, and Utama. The number of sampling is 1-2 samples/urban village. Based on the results of the analysis of parameters that do not exceed the required quality standards based on the Regulation of the Minister of Health of the Republic of Indonesia No. 32 of 2017 concerning the requirements and supervision of pristine water quality, namely: turbidity, Manganese, nitrate, detergent as MBAS, and total coliform. Based on the results of calculations with the water quality index, it is stated that the quality of groundwater in Cimahi City is in the normal-poor category.

Optimization of Rain Gauge Networks for Arid Regions Based on Remote Sensing Data

Water depletion is a growing problem in the world’s arid and semi-arid areas, where groundwater is the primary source of fresh water. Accurate climatic data must be obtained to protect municipal water budgets. Unfortunately, the majority of these arid regions have a sparsely distributed number of rain gauges, which reduces the reliability of the spatio-temporal fields generated. The current research proposes a series of measures to address the problem of data scarcity, in particular regarding in-situ measurements of precipitation. Once the issue of improving the network of ground precipitation measurements is settled, this may pave the way for much-needed hydrological research on topics such as the spatiotemporal distribution of precipitation, flash flood prevention, and soil erosion reduction. In this study, a k-means cluster analysis is used to determine new locations for the rain gauge network at the Eastern side of the Gulf of Suez in Sinai. The clustering procedure adopted is based on integrating a digital elevation model obtained from The Shuttle Radar Topography Mission (SRTM 90 × 90 m) and Integrated Multi-Satellite Retrievals for GPM (IMERG) for four rainy events. This procedure enabled the determination of the potential centroids for three different cluster sizes (3, 6, and 9). Subsequently, each number was tested using the Empirical Cumulative Distribution Function (ECDF) in an effort to determine the optimal one. However, all the tested centroids exhibited gaps in covering the whole range of elevations and precipitation of the test site. The nine centroids with the five existing rain gauges were used as a basis to calculate the error kriging. This procedure enabled decreasing the error by increasing the number of the proposed gauges. The resulting points were tested again by ECDF and this confirmed the optimum of thirty-one suggested additional gauges in covering the whole range of elevations and precipitation records at the study site.

Distributions and interactions of dissolved organic matter and heavy metals in shallow groundwater in Guanzhong basin of China

Groundwater as the primary source of fresh water particularly in semi-arid regions is heavily threatened by various pollutants such as dissolved organic matter (DOM) and heavy metals due to anthropogenic activities. In this study, 113 shallow groundwater samples were collected from Guanzhong basin of China to explore spatial distributions and interactions of DOM and heavy metals (Fe, Mn and Cu). Fluorescence excitation-emission spectrophotometry with parallel factor analysis showed that DOM in groundwater mainly contained three humic-like and two protein-like substances with an average dissolved organic carbon (DOC) concentration of 12.85 mg L−1. Average Mn and Cu concentrations in groundwater were 19.92 μg L−1 and 7.05 μg L−1 with an increasing trend from west to east, whereas Fe concentration in central regions was much higher (34.23 μg L−1). Structural equation modeling analysis indicated that DOM in groundwater could be significantly affected by surface water, and heavy metals were influenced by urbanization. Moreover, DOM could strongly influence the bioavailability, migration, and transformation of Mn in groundwater. These findings would be beneficial for the effective utilization and protection of groundwater resources.

Hydrogeochemical Characteristics of Hot Springs and Their Short-Term Seismic Precursor Anomalies along the Xiaojiang Fault Zone, Southeast Tibet Plateau

Significant hydrogeochemical changes may occur prior- and post-earthquakes. The Xiaojiang fault zone (XJF), situated in a highly deformed area of the southeastern margin of the Tibetan Plateau, is one of the active seismic areas. In this study, major and trace elements, and hydrogen and oxygen isotopes of 28 sites in hot springs along the XJF were investigated from June 2015 to April 2019. The meteoric water acts as the primary water source of the hot spring in the XJF and recharged elevations ranged from 1.8 to 4.5 km. Most of the hot spring water in the study area was immature water and the water–rock reaction degree was weak. The temperature range was inferred from an equation based on the SiO2 concentration and chemical geothermal modeling: 24.3~96.0 °C. The circulation depth for the springs was estimated from 0.45 to 4.04 km. We speculated the meteoric water firstly infiltrated underground and became heated by heat sources, and later circulated to the earth’s surface along the fault and fracture and finally constituted hot spring recharge. Additionally, a continuous monitoring was conducted every three days in the Xundian hot spring since April 2019, and in Panxi and Qujiang hot springs since June 2019. There were short-term (4–35 d) seismic precursor anomalies of the hydrochemical compositions prior to the Xundian ML4.2, Dongchuan ML4.2, and Shuangbai ML5.1 earthquakes. The epicentral distance of anomalous sites ranged from 19.1 to 192.8 km. The anomalous amplitudes were all over 2 times the anomaly threshold. The concentrations of Na+, Cl−, and SO42− are sensitive to the increase of stress in the XJF. Modeling on hydrology cycles of hot springs can provide a plausible physicochemical basis to explain geochemical anomalies in water and the hydrogeochemical anomaly may be useful in future earthquake prediction research of the study area.

Shifting to energy efficient hybrid cooled data centers using novel embedded floor tiles heat exchangers

With the remarkable surge in IT power densities and energy consumption, the data center industry is starting to adopt energy and thermally-efficient single-phase cooling technologies. For many legacy data centers worldwide, the lack of a primary chilled water source is a substantial barrier to adopting single-phase technologies. In this study, the necessity of having a facility chilled water source for deploying liquid cooling solutions is eliminated by introducing a solution that does not require bringing in any modification of the data center layout. This simple solution proposes integrating liquid to air heat exchangers with the floor tiles to eject heat from the liquid-cooled IT equipment into the room air. An experimentally validated CFD modeling approach is used to investigate the performance of these heat exchangers. Results show that by installing two heat exchangers in different cold aisles, a significant amount of cooling load is handled at the design point conditions. When they are tested under different operational conditions, the cooling capacity of these heat exchangers is shown to be sensitive to the supply air temperature. To overcome the operational constraints stemming from the supply air temperature, an alternative configuration with just one heat exchanger installed in the hot aisle is considered and discussed. Results indicate that the second configuration shows superior performance to the first one in terms of sensitivity to supply air temperature and cooling capacity. Lastly, with this configuration, the data center utilizes energy extremely efficiently and achieves a power usage effectiveness of 1.06.

Water, sanitation, and hygiene in healthcare centres: appraisal in a pandemic

Abstract Assessment of water, sanitation, and hygiene (WASH) facilities in Primary Healthcare Centres (PHCs) and water source quality in parts of Southwestern Nigeria was conducted. Sixty-one PHCs in urban and rural areas were selected using a stratified random sampling technique. A WASH profile of the PHCs was conducted based on the water source type, type of toilet facilities, and handwashing practice using the Joint Monitoring Programme service ladder for monitoring WASH services in healthcare facilities. Water sources were tested for pH, electrical conductivity, total dissolved solids, turbidity, chloride, nitrate, and E. coli. Boreholes and hand-dug wells are the most prevalent water source type, and flush toilets and pit latrines are the major types of toilet facilities used. All but two PHCs engaged in handwashing practices. Water quality analysis results showed that chloride, nitrate, and turbidity were within the WHO drinking-water standards. Poor water quality and sanitation practices could expose health staff and patients to healthcare-associated infections. The study recommends the construction of safe, secure and accessible water sources and toilet facilities, provision of water treatment facilities, and the training of staff and patients on the significance of handwashing practices.

An Approach to Drought Vulnerability Assessment Focused on Groundwater Wells in Upland Cultivation Areas of South Korea

This study aimed to present an approach that identifies priority management areas to drought focused on field crops and groundwater wells using the MCDM method. Groundwater wells are the primary source of water during drought for field crops. Nevertheless, the systematic management of groundwater wells has not been achieved. Thus, this paper intends to establish a plan that can manage groundwater wells through a vulnerability assessment. This study used TOPSIS, a widely applied multi-criterion decision-making algorithm, to evaluate 158 cities and counties in Korea. This study chose the assessment factors by focusing on drought and classifying the positive and negative elements of the wells. Precipitation, groundwater level, and pumping capacity were considered to have positive effects, while cultivated area, the number of consecutive days without rain, and the proportion of private groundwater wells were considered as negative factors. As a result, the pumping capacity per cultivation area is the major factor affecting management priorities and groundwater well vulnerability. This study presents an approach to assess the drought vulnerability of field crops focused on groundwater wells and select a priority management area, which facilitates efficient well management and reduces damage to crops caused by local droughts.