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Groundwater extraction for irrigation in Bangladesh has caused groundwater depletion, especially in the Northern region. As such, shifting reliance from groundwater to surface water is one of the solutions to mitigate this problem. This study aims at investigating the contribution of effective rainfall to the total consumptive use requirement of rice cultivated in Tanore, Rajshahi, in Bangladesh. The prospect of rainwater harvesting using ponds and its contribution to the consumptive use requirement of rice was also determined. Effective rainfall, temperature, monthly percentage of bright sunshine hours, and consumptive use factor for rice data were collected from Bangladesh Meteorological Department (BMD) and Barind Multipurpose Development Authority (BMDA). Blaney-Criddle method was used to calculate total consumptive use requirement of rice. Analysis results showed that from June to September, there is no requirement of irrigation due to high rainfall in this period. It was revealed that total consumptive use requirement of rice in Tanore averaged at 436 million m3 of water between the period of 2005 and 2012. Effective rainfall contributed to about 38% of the total consumptive use in this period. It was also found that another 5% of the total consumptive use requirement could be supplied by rainwater harvesting using the ponds of Tanore.
New trends related to market incomes, cultural human development, non-sustainable soil management practices, and climate change are affecting land abandonment in Mediterranean sloping vineyards. It is generally accepted that hydrological processes and, subsequently, soil erosion rates are usually different between cultivated and abandoned soils. However, these alterations are still poorly studied in relation to the general weather conditions in vineyards and abandoned vineyards. Thus, the main goals of this research are to (1) estimate the differences in soil properties, (2) quantify water and soil losses due to rainfall and specific soil management practices, and (3) analyze which kind of weather type and rainfall event is able to generate specific surface flows and soil loss rates. To achieve these goals, we focused on the specific case of the sloping vineyards of the Montes de Málaga (South Spain). We used 4 paired-erosion plots with Gerlach troughs to quantify soil loss and surface flow and conducted an analysis of the weather conditions during each rainfall event. The weather types that generated the highest amount of rainfall in the studied area came from the western (32.6%) and southeast (28.2%) types. The low rainfall events came from the south type (5.9%) and at the 500 hPa level, whereas the rainiest ones came from the southwest (47.7%) and south (34.1%). It is confirmed that there is a bimodality in the rainfall patterns. The results of soil erosion showed that there is a mixed mechanism depending on the state of the soil (vegetation cover, compaction, and initial soil moisture), soil management (tillage, trampling effect, and the use of herbicides). It is observed that the intensity of surface flow is highly correlated to the total rainfall amount and intensity. In the poorly managed abandoned plot, it is important to remark that the effect of tillage in the past, the elimination of the vegetation cover to preserve the soil in bare condition, and its use as a grazing area by cultivating barley highly affects the generation of the highest erosive events. Therefore, it is confirmed that these soil management options are not the most sustainable way to conserve the soil after the abandonment of cultivation.
Institutional design for local air quality management is an underdeveloped area for research and practice. Although the United States has more than a century of organizational experience managing air quality at the Federal level, the recent years have seen a surge of interest in addressing municipal-scale solutions. Without information about the institutional designs, governance structures, and implications of localizing air quality management, practitioners may face challenges reducing population exposure to air pollutants. We offer a US national perspective on managing local air quality by assessing and surveying 117 local air quality authorities identified by the National Association of Clean Air Agencies. The results expose many commonalities and differences among local air quality management agencies across the United States. We find that the authority type and motivations for creating the local air quality agency drive much of the organization structure and capacity to fulfill mandates. The results further provide a means for evaluating the opportunities and challenges for creating local air quality agencies, while recognizing the factors that support effective institutional designs.
The adsorption of entrapped activated carbon in alginate polymer (AG–AC) was investigated by measuring the removal of organic compounds. The general concept is that the entrapped activated carbon in alginate polymer could be used as a low–cost adsorbent for ascorbic acid and lactose removal from industrial wastewater. Ascorbic acid and lactose are the most pharmaceutical wastes that can introduce throughout the industrial process and lead to an increase in the amount of chemical oxygen demand (COD) in wastewater. Different ascorbic acid and lactose concentrations were prepared in the laboratory. The efficient removal is affected by external variables (eg, pH, contact time, adsorbent dosage, concentrations, and stirring rate). Percent removal for ascorbic acid and lactose at pH 3 using dose 30 g for 60 minutes with a fixed stirring rate at 100 rpm was about 70% and 50%, respectively. Ascorbic acid and lactose adsorption onto entrapped activated carbon in alginate polymer obey well with Freundlich adsorption isotherm.
The objective of this study is to evaluate the public water contamination in the cities of Midland and Odessa, West Texas. Even though both cities are geographically close, their sources of water for public use are different. For this study, the copper-, lead-, arsenic-, nitrate-, and chromium-level reports in drinking water, provided by the cities from 2008 to 2017, were organized and analyzed using Cubic Hermite Interpolation. The results for each contamination per city were compared and contrasted with the Environmental Protection Agency (EPA) standards. Also, this study proposed possible risks to human health, as well as potential origins of the pollutants. Finally, conclusions about the quality of water for human consumption and possible reasons behind the difference of results between the 2 cities were made.
Contamination from septic systems is one of the most difficult sources of nonpoint source (NPS) pollution to quantify. Quantification is difficult in part because locating malfunctioning septic systems within a watershed is challenging. This study used synthetic-DNA-based tracers to track flows from 2 septic systems. Sample DNA was quantified using quantitative polymerase chain reaction (qPCR). This technology could be especially useful for simultaneously assessing multiple septic systems because there are essentially infinite unique combinations of DNA bases such that unique tracers could be engineered for each septic system. Two studies were conducted: the first, to determine whether the tracers move through septic systems (experiment 1), and the second, to determine whether the tracers were detectable at watershed scales (experiment 2). In both cases, clear, although complex, breakthrough curves were detected. Experiment 1 revealed possible preferential flow paths that might not have been otherwise obvious, indicative of short circuiting systems. This proof of concept suggests that these tracers could be applied to watersheds suspected of experiencing NPS septic system pollution.
Precise estimation of metals in samples remains a challenge as a result of analytical biases and errors, which occur at sample collection, preparation, and measurement stages. A poor understanding of the nature and occurrence of these errors further aggravates this challenge. This study aimed at comparing the effectiveness of inductively coupled plasma (ICP) mass spectrometry (MS) and optical emission spectrometry (OES) techniques in quantifying metals from contaminated soils of Roundhill landfill vicinity. Using statistical tools, the study evaluated biases of the 2 methods. High coefficients of variation were realized for V, Cr, and Pb concentrations varied at various sampling sites. Concentrations of elements obtained using the 2 methods had no significant differences using t-test analysis. Definitive agreement for the 2 methods was observed for V, Cr, Co, Ni, Cu, Zn, Sr, and Pb concentrations, whereas the concentrations of Mg, Ca, Ti, Mn, and Fe showed some deviations in their regression lines. Spectral, systematic, memory, and carry over errors could be attributable to these deviations. The errors promote chelation and adsorption of ions in samples to form insoluble compounds that cannot be quantified. Overall, ICP-MS had greater sensitivity than ICP-OES in trace elements analysis compared with major elements.
Soil fumigants, such as 1,3-dichloropropene (1,3-D), are used on a variety of different crops in high use areas in the United States, including the Pacific Northwest, the mid-Atlantic coast, and the Southeast coastal plains. Contaminant concentrations in air are often required for environmental exposure and human risk assessment. The SOil Fumigant Exposure Assessment (SOFEA) model, originally developed to explore volatile pesticide exposure and bystander risk, has recently been upgraded using AERMOD, the US Environmental Protection Agency’s (EPA) recommended regulatory air dispersion model to predict short-, medium-, and long-term pesticide concentrations in air resulting from representative agronomic practices in large airsheds. Modeling air concentrations has several advantages over monitoring such as the ability to predict concentrations at multiple locations and airsheds at a much greater temporal frequency than could be practically accomplished through monitoring alone. The agricultural modeling tool presented herein was parameterized using 1,3-D application data (mass, date, and depth applied, location, etc) obtained from growers in each study area, and local weather data and hourly concentrations of 1,3-D in ambient air were simulated for large airsheds. The human equivalent concentrations (HECs) for acute, short-term, sub-chronic, and chronic exposure of 1,3-D were not exceeded in any of the study areas investigated. These simulated 1,3-D concentrations are used to assess human exposure and risk, which considers human-life-stage-specific exposure factors, including residential mobility, time-activity patterns, and age-specific inhalation rates and body weights.
Coastal areas are attractive for human settlements because they allow easy access to benefits like food, security, and fishing. These aquatic ecosystems are supported by photosynthetic organisms that constitute the base of the food web. The term “Harmful Algal Bloom” (HAB) refers to the excessive proliferation of some taxa of these microorganisms reaching harmful levels to humans and other organisms. Biotoxins produced by these HABs could be transferred to the food chain and are the best-documented impact that HABs have on humans. The location and abundance of the HAB species producing the toxin is a good indicator of a possible human health hazard. The aim of this study was to monitor potentially harmful benthic/epibenthic microalgae in Punta Galeta, Panama over a 15-month period. The 3 main microalgae found were 2 dinoflagellates from the genera Prorocentrum and Ostreopsis and 1 diatom from the genus Coscinodiscus. Sampling made with both natural and artificial substrates yielded similar overall abundance patterns; however, for the macroalgae samples, there appeared to be significant host preferences for Ostreopsis and Coscinodiscus. Physicochemical measures taken at the site were found to fall within previously reported growth parameters for the microalgae found in the study.
Groundwater is the most reliable resource for consumptive uses worldwide, but it is vulnerable to anthropogenic pollution in this post-industrialization era. Pollution of the resource may result from anthropogenic activities; hence, analysing the effects of leachate on groundwater is imperative. This study assessed the spatial distribution of physicochemical parameters of groundwater in Roundhill landfill vicinity of South Africa and conducted their hydrogeochemical analysis. Water samples were collected from 3 boreholes in the landfill surroundings and analysed for selected physicochemical characteristics. Spatial distribution of these parameters showed dominant pollution by Mn2+, Fe2+, and NH4+, which surpassed prescribed allowable limits of the country in most of the study area. Possibilities of simple dissolution and ion mixing were deduced from the Durov diagram. Magnesium carbonate, sodium chloride, and mixed faces of groundwater were dominant in boreholes 1 to 3, respectively. The dominance of Ca2+, Cl−, Mg2+, and NH4+ ions in some boreholes suggested anthropogenic pollution. Landfill leachate was associated with groundwater pollution in the study area.
This study deals with the effects of flooding on alluvial soils and riparian forests in the basins and sub-basins of southern Québec (Canada). These riparian environments are sensitive to hydroclimatic variations, which may increase with current climate change, which is why it is important to analyse them. The study areas were divided by flood frequency based on government maps that show flood recurrence intervals of 0 to 20 years and 20 to 100 years. Woodlands located outside of the floodplains were also analysed for comparison to measure and better determine the effect of floods on soils and forest stands. Soil depletion is found in the frequent-flood zones (FFZ), which results in lower total organic carbon (mean values of 1.9%-3.7% in FFZ vs 3.2%-5.9% in no-flood zones [NFZ]) and total nitrogen (mean values of 0.1%-0.2% in FFZ vs 0.2%-0.3% NFZ). Field observations and measurements show that the aboveground biomass (plant litter) is reduced or absent from the active flood zones. The structure and composition of tree stands are relatively comparable from one zone to another, but a slightly lower rate of small (5-10 cm dbh [diameter at breast height]) and intermediate (10-15 cm dbh) trees can be noted in FFZ, and tree diversity (Shannon index) and species richness are also slightly lower. The mechanical action of water in trees during floods and the burial of seedlings through the accumulation of fine alluvial deposits could negatively impact forest regeneration in active floodplains.
Combustion of solid biomass fuel (SBF) releases a high concentration of airborne pollutants, resulting in household air pollution (HAP). HAP is considered as a leading risk factor for the development of various respiratory diseases. The increased exposure to HAP significantly affects the health of the vulnerable population, including the women, elderly, and children who stay indoors for most of the time. Considering this, self-reported respiratory health symptoms were assessed using a standard American Thoracic Society (ATS) questionnaire, whereas lung function capacity of women using SBF, liquefied petroleum gas (LPG) and mix fuels were assessed using a cross-sectional study design. Lung function capacity was examined with help of spirometry. Results suggest that compared with LPG users, SBF and mix fuel users had a relatively high prevalence of phlegm (25.7%), cough (54%), and eye irritation (74.3%). Use of SBF was found to be associated significantly with lower forced expiratory volume in the first second of expiration (FEV1) values (P < .01). The study concludes that women cooking with SBF and mix fuels have an impact on lung function and increased prevalence of respiratory symptoms. The findings suggest that women who cook using LPG have improved lung function and respiratory health status. Hence, it is suggested to increase the scope of clean fuel programmes such as Pradhan Mantri Ujjwala Yojana (PMUY) by identifying the barriers for the choice of clean fuel uses for household energy.
The United Kingdom has a problem in the disposal of municipal green waste (MGW). This is unsuitable for landfill, but when properly composted may be beneficial to tree growth. A formal controlled trial of the 11-year growth (height, diameter at breast height [DBH]) and survival of 3 tree species was evaluated on degraded former opencast coal land on the margins of UNESCO’s Blaenavon Industrial Landscape World Heritage site in South East Wales. Forest reclamation is considered a viable cost-effective approach to reclamation but success may be compromised by infertile and seriously compacted substrates, the depleted bio-geoecological system, and a lack of funding. In this trial, trees were (or were not) supplied, on planting, with 0.75 kg per stem of composted MGW – here a mixture of 40% domestic food waste and 60% garden waste. Results show that the application of MGW made no significant difference to either tree height or DBH. Survival rates were highest for Common Alder (Alnus glutinosa (L.) Gaertn.) followed by Silver Birch (Betula pendula, Roth) and European Larch (Larix decidua Mill.). However, Silver Birch and Larch treated with MGW compost had significantly greater survival rates, whereas Alder had significantly lower survival rates, compared with trees planted without MGW treatment.
Zero-valent metals proved high reactivity to adsorb and degrade various contaminants removal. The chemically prepared nZVAl was characterized using UV-Vis spectrum, X-ray diffraction (XRD), and scanning electron microscope (SEM). This investigation explores the adsorption effect of nZVAl powder toward soluble organic compounds exemplified by chemical oxygen demand (COD) standard solution. The effect of different operating parameters was studied to identify the best removal conditions. All variable and covariable data were introduced to build statistical models. The effect of the operating parameter was studied at different pH (3-10), nZVAl dosages (0.1-0.8 g), at different times (5-120 minutes), stirring rate (50-400 RPM), and initial COD concentration (100-800 mg/L). The obtained results displayed that nZVAl is effective in the removal of standard COD solutions, where the removal percentages were 56% and 96% for 800 ± 18.0 and 100 ± 11.8 mg/L COD, respectively, at 10 minutes after using nZVAl dry dosage 0.6 g/L, pH 8, and rate 100 rpm. Also, the effect of nZVAl on other wastewater contaminants removal was studied and compared with Egyptian law for draining wastewater into nonfresh water (drainage-lakes-ponds) No. 48 of 1982 limits. The results of adsorption isotherm and kinetic model of COD fitted well to Freundlich isotherm and pseudo second order, respectively. Nonlinear artificial intelligence neural network (ANN) importance data agree with linear response surface methodologies (RSM) in simulating the adsorption of COD onto nZVAl indicating that the most significant coverable is adsorbent dose. Finally, this study appropriates using nZVAl in highly contaminated wastewater rather than other chemical and biological processes.
Cavitation is considered a high energy demanding process for water treatment. For this study, we used a simple experimental setup to generate cavitation at a low pressure (low energy) and test it for hydroxyl radical production using a well-known chemical probe as a hydroxyl radical scavenger. The conditions for generating the cavitation process (eg, pressure, flow velocity, temperature, and other significant variables) were used to degrade model contaminants, an azo dye and an antibiotic. The amount of hydroxyl radicals generated by the system was estimated using N,N-dimethyl-p-nitrosoaniline (pNDA) as hydroxyl radical scavenger. The capability of hydrodynamic cavitation (HC) to degrade contaminants was assessed using Congo red (CR) and sulfamethoxazole (SMX) as model contaminants. Different chemical models were analyzed using UV-visible spectrophotometry (for pNDA and CR) and high-performance liquid chromatography (HPLC) (for SMX) after HC treatment under different process conditions (ie, pressure of 13.7 and 10.3 kPa, and flow rates of 0.14 to 3.6 × 10−4 m3/s). No pNDA bleaching was observed for any of the reaction conditions tested after 60 minutes of treatment, which suggests that there was no hydroxyl radical generation during the process. However, 50% degradation of CR and 25% degradation of SMX were observed under the same process conditions, comparable with previously reported results. These results suggest that the process is most likely thermally based rather than radically based, and therefore, it can degrade organic pollutants even if no hydroxyl radicals are produced. Hydrodynamic cavitation, either alone or coupled with other advanced water technologies, has been identified as a promising technology for removing organic contaminants entering the water cycle; however, more research is still needed to determine the specific mechanisms involved in the process and the optimal operation conditions for the system.
The work reported in this article raises some serious concern about the drinking water quality and its standards. Mere presence or absence of an indicator organism does not assure that the water is safe for drinking purposes. Instead of infecting directly, many pathogens pass through a host and retrieve their virulent properties by causing diseases/infections in humans. Pathogenic bacteria which exist in aquatic habitats show a unique and peculiar pattern of appearing or reappearing in different microenvironments. Several factors that prevail in the water system make a safe house for the growth, proliferation, and colonization of microorganisms. In our case, 6 different microenvironments inside the premises of an office building were taken as the sampling sites to study the effect of seasonal variations (summer, monsoon, and post-monsoon/winter) on bacterial diversity and inhabitants. Results suggested that the presence of total and thermotolerant coliforms were highest in the monsoon followed by summer and post-monsoon/winter seasons. To know the bacterial diversity and pattern of appearance/reappearance prevailing in the water system, bacterial strains were analyzed by 16S rRNA sequencing which showed Pseudomonas putida to be the predominant identified bacterial strain occurring about 38% to 77% in all 3 seasons. This was followed by Lelliottia nimipressuralis (6%-21%), Escherichia coli (4%-18%), Salmonella typhimurium and Aeromonas dhakensis (4%-10% each), and Klebsiella pneumoniae (5%-6%). Despite the absence of other opportunistic bacteria, P putida was reported to be present as a single organism in water coolers and dispensers. This might be due to the persistent nature of P putida in low-nutrient environments and capable of colonizing by forming a rigid biofilm inside the water cooler/dispenser which makes a conducive environment for it.
A hydrogeochemical relation has been hypothesized through the analyses of physiochemical data of a fractured volcanic rock aquifer located in the Lower Baringo Basin, Kenyan Rift. Data sets included 15 individual metrics determined in 42 dry and wet season water samples obtained from 6 boreholes in the area. Aquifer evolutionary theory was postulated using sequential principal component analysis (PCA) and hierarchical cluster analysis. To eliminate the effects of scale dimensionality, PCA decomposed the variable data into 4 factors, namely, electrical conductivity, salinity, alkalinity, and carbonate equilibrium with external pH control for the dry season and salinity, carbonate equilibrium with external pH control, alkalinity, and electrical conductivity for the wet season. The main result depicted a major shift in the variability factor from electrolytic conductivity (34.8%) in the dry season to salinity (23.5%) in the wet season. Ward’s linkage cluster analysis partitioned the aquifer into 2 spatially discrete associations; the western and the eastern entities, respectively, in spite of their shared recharge area. These agglomerative scheduling validated in an integrative approach (with groundwater flow predictions using a calibrated petrophysical groundwater model for the area) linked the 4 factors to aquifer processes and 3 pathways: fault permeability, weathering processes, and water-rock interaction. Statistical approaches are, therefore, useful in the conceptualization of pollutant sources and their attenuation for effective groundwater quality management.
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