Remediation Techniques Research Articles

Investigating Preschool Teachers’ Pedagogical Content Knowledge of Number Comparison

ABSTRACT Research Findings: The aim of this study was to investigate U.S. preschool teachers’ math pedagogical content knowledge in number comparison. Seventy-four in- and pre-service teachers completed a set of scenario-based questions from a researcher-designed questionnaire that is composed of learning scenarios. Through a mixed-method approach, the study revealed the following findings: a considerable portion of participants (89%) successfully identified the concept of number comparison embedded in a learning scenario, showcasing their specialized content knowledge. However, when it came to knowledge of content and students, only 24 participants (32%) were able to pinpoint both a child’s mathematical strength and area of need. In terms of knowledge of content and teaching, more than half of the participants (51%) recommended the utilization of hands-on materials and/or visual aids as part of their remediation techniques, while 49% did not reference these educational tools. Notably, no significant differences were observed between the pedagogical content knowledge of pre-and in-service teachers concerning number comparison. Practice or Policy: The findings indicate that teacher education and professional development should focus on helping teachers understand children’s learning trajectories on number comparison and include instructions on using concept specific developmentally appropriate strategies, and indicate that teaching experience cannot replace professional training.

Solar-driven self-sustaining remediation of petroleum-contaminated soil

Petroleum-contaminated soil poses an environmental risk and is costly to remediate. Self-sustaining Treatment for Active Remediation (STAR) is an emerging remediation technique that consists of igniting and propagating a smoldering front through a volume of contaminated soil. While effective, the electrical energy demand required to initiate smoldering can be cost-prohibitive in locations without robust electrical infrastructure. To address this, we investigated the viability of a novel concentrated solar power process as a low-carbon alternative to electrically driven heating for STAR. The solar-driven system uses parabolic reflectors to focus solar energy, then directs it through fiber optic bundles to flexibly transmit it to a soil column. This process is demonstrated on ∼ 750 mL samples of petroleum-contaminated soil and detectable hydrocarbons were reduced in each case. Research evaluated several parameters of interest for effective treatment including thermal receiver material and distance between solar output and thermal receiver. Temperature was measured throughout treatment and typically exceeds 400 °C prior to ignition. Steel and quartz thermal receivers show effective temperature distribution, initiating smoldering, reducing detectable hydrocarbons and maintaining durability. The results indicate that concentrated solar power can efficiently ignite smoldering remediation, showing promise as a low-carbon alternative to current methods.

Innovative Approaches for Microplastic Pollution Detection and Remediation in Aquatic Ecosystems

Microplastic pollution in aquatic ecosystems is a pressing environmental issue, posing significant threats to marine life and human health. Traditional detection and remediation methods are often inadequate, necessitating the development of innovative approaches. This research aims to explore and evaluate novel techniques for detecting and mitigating microplastics in aquatic environments. The study investigates advanced detection technologies, including spectroscopy and sensor-based methods, that offer higher accuracy and efficiency compared to conventional approaches. Additionally, it explores innovative remediation techniques such as bioremediation and the use of advanced filtration systems. Field and laboratory experiments were conducted to test the effectiveness of these methods in various aquatic settings. The results indicate that these innovative approaches significantly enhance the detection and removal of microplastics, demonstrating superior performance over traditional methods. This research provides critical insights into the potential of advanced technologies in addressing microplastic pollution, highlighting their applicability and benefits for environmental conservation. By integrating these innovative solutions, we can better safeguard aquatic ecosystems and promote sustainable environmental practices.

PFOA-contaminated soil remediation: a comprehensive review.

Soil and groundwater contamination has been raised as a concern due to the capability of posing a risk to human health and ecology, especially in facing highly toxic and emerging pollutants. Because of the prevalent usage of perfluorooctanoic acid (PFOA), in industrial and production processes, and subsequently the extent of sites contaminated with these pollutants, cleaning up PFOA polluted sites is paramount. This research provides a review of remediation approaches that have been used, and nine remediation techniques were reviewed under physical, chemical, and biological approaches categorization. As the pollutant specifications, environmental implications, and adverse ecological effects of remediation procedures should be considered in the analysis and evaluation of remediation approaches, unlike previous research that considered a couple of PFAS pollutants and generally dealt with technical issues, in this study, the benefits, drawbacks, and possible environmental and ecological adverse effects of PFOA-contaminated site remediation also were discussed. In the end, in addition to providing sufficient and applicable understanding by comprehensively considering all aspects and field-scale challenges and obstacles, knowledge gaps have been found and discussed.

Impact of soil and water quality on the sustainable management of mangrove-compatible brackishwater aquaculture practices in Indonesia

The widespread degradation of mangroves has been attributed to their conversion into other land uses and purposes, most notably their destruction to construct extensive brackishwater aquaculture ponds. This study investigated the relationship between environmental factors and management alternatives for an integrated mangrove-aquaculture system in Derawan Island District, Berau Regency, East Kalimantan Province, Indonesia. The study collected a total of 56 soil and water samples from around 50 ha to assess environmental limiting factors for integrated mangrove-brackishwater aquaculture management. The measured soil quality variables included field pH (pHF), pH of hydrogen peroxide extract (pHFOX), peroxide oxidizable sulfur (SPOS), pyrite (FeS2), organic matter (OM), nitrogen-total (N-TOT), iron (Fe), and aluminum (Al). Water quality variables included salinity, temperature, pH, dissolved oxygen (DO), different forms of nitrogen (NH3–ammonia, NO3–nitrate, and NO2–nitrite), phosphate (PO4), Fe, and total organic matter (TOM). The study employed a hydrological restoration approach to suggest a mangrove-friendly aquaculture pond design and layout. The study generally showed that Acid Sulfate Soils (ASS) significantly restricted the existing mixed-mangrove aquaculture pond management by negatively impacting water quality. This study highlights that, given the characteristics of ASS-affected aquaculture ponds, reducing pond size for shrimp culture (mangrove-to-pond ratio of 80% and 20%) will simplify managing ASS environmental limiting factors through cost-effective remediation techniques and a Balanced Fertilization Strategy (BFS). The reduced shrimp pond size will also provide direct opportunities for mangrove restoration and allow effective hydrological restoration. The economic benefit of the proposed pond design and management model focuses on diversifying production units which include shrimp aquaculture ponds, milkfish or tilapia culture in the peripheral canals of the mangrove compartment, juvenile shrimp production, and periodic harvest from the primary pond canal. The study findings are particularly applicable to ponds that have already been built in ASS to improve productivity in addition to supporting the mangrove rehabilitation program. Converting mangrove and ASS-affected land is not advisable for constructing new aquaculture ponds.

Environmental risk assessment of pharmaceuticals in wastewaters and reclaimed water from catalan main river basins

Aquatic pollution from pharmaceuticals is a growing environmental concern globally, particularly in Catalonia's primary water bodies, the Llobregat and Besòs rivers. This study investigates pharmaceutical residues in reclaimed water effluents from the Llobregat River and a wastewater treatment plant (WWTP) in the Besòs River, critical contributors to the region's water resources. Employing LC-MS/MS, 85 pharmaceutical residues were monitored, revealing elevated concentrations of tramadol, losartan, and gemfibrozil, commonly prescribed drugs in Catalonia. Surprisingly, downstream concentrations exceeded upstream levels significantly, indicating the adverse impact of reclaimed water on water quality. Furthermore, evaluation of WWTP efficiency displayed varying removal rates, from 10 % to 99.8 %, highlighting treatment inadequacies for certain compounds. Predictive environmental concentrations (PECs) aligned closely with measured values, affirming the utility of predictive models in early-stage research. Risk assessment via the risk quotient (RQ) method identified atorvastatin and chlorpromazine as surpassing toxicity thresholds.This study underscores the urgent need to address pharmaceutical contamination in urban rivers and reclaimed waters in Catalonia. By highlighting treatment inefficacies and potential ecological risks, it contributes to the development of sustainable water management strategies and environmental conservation efforts in the region. Efforts should focus on continuously monitoring specific compounds, evaluating their individual toxicity, and implementing appropriate remediation techniques in WWTPs to safeguard water quality and aquatic ecosystems.

Synergistic Methods for Chromium Cleanup Using Plant-Growth-Promoting Bacteria

Chromium (Cr) pollution contributes a significant threat to environmental and human health due to its widespread industrial use and toxic effects. Among the various remediation strategies, the application of plant-growth-promoting bacteria (PGPB) has emerged as a promising approach. The article explores the synergistic potential of PGPB in enhancing plant-based remediation techniques for chromium cleanup. PGPBs enhance plant growth and stress tolerance through mechanisms such as hormone production, nitrogen fixation, and pathogen inhibition. Key strategies discussed include bioaugmentation, biostimulation, phytoextraction, and phytostabilization. These methods leverage the abilities of PGPB to promote plant growth, enhance chromium uptake, and immobilize chromium in the soil, thereby reducing its bioavailability and mobility. Case studies and experimental evidence highlight the effectiveness of PGPB in chromium-contaminated environments, demonstrating improved plant growth and metal accumulation. This review underscores the need for interdisciplinary collaboration, field-scale implementation, and ongoing research to harness the full potential of PGPB-mediated phytoremediation for sustainable chromium cleanup.

The use of bioremediation as a technique to treat oil-contaminated effluents

Demographic growth has increased the demand for natural resources, especially in oil exploration, which, despite its benefits, has negative environmental and social impacts. The occurrence of environmental accidents, such as oil spills, highlights the need for effective remediation methods. Bioremediation, using microorganisms or plant products, has emerged as a promising technique for treating contaminated effluents. This study analyzes the effectiveness of the main bioremediation techniques, highlighting advantages such as low cost, easy implementation and sustainability compared to other remediation techniques, being sustainable, not causing disruption to ecosystems and aiming exclusively at the biodegradation of petroleum polluting compounds.

Environmental Implications of Energy Sources: A Review on Technologies for Cleaning Oil-Contaminated Ecosystems

This review analyzes the main methods for cleaning up oil pollution in natural ecosystems, with a particular focus on the synergy between chemical and microbiological techniques for environmental remediation. While biological methods are a green and inexpensive soil remediation technique, they have a major limitation in their inability to clean up high concentrations of toxic contaminants. The poor performance of chemical methods stems from the high cost of chemicals and concerns over their negative and toxic effects on the environment. Physical methods also have high costs due to energy consumption and the need for additional treatment of gases generated during decontamination, making them ineffective for soil remediation. The main principle of bioremediation is based on microorganisms’ ability to degrade complex organic compounds, such as petroleum. This process is described in this review. This combination of methods allows for a higher level of decontamination of soil and water ecosystems, even against pollutants that are usually resistant to degradation, such as oil derivatives. While existing methods for cleaning oil-contaminated ecosystems are highly effective, they require significant material costs to implement. Additionally, the review discusses how the joint use of current and future biotechnology techniques can lead to the development of an effective set of strategies to protect soil and water systems from oil pollution. The reviewed studies show that a hybrid biotechnological approach is the most effective remediation method. When biological decontamination methods are adopted, the optimized combination of different remediation strategies can overcome the limitations of each technique, allowing efficiencies of even more than 70% to be achieved, given that the choice still depends on the type of contaminant, its concentration, and the properties of the receiving substrate.

Seasonal variation effect on water quality and sediments criteria and its influence on soil pollution: Fayoum Governorate, Egypt

BackgroundIrrigation with low-quality water without considering the acceptable levels negatively impacts not only humans, but also extends to the whole surrounding ecosystem. The current research is a comprehensive-integrated appraisal of the irrigation water quality gathered from El-Batts drain in Fayoum Governorate, from September 2021 to June 2022, together with the drain sediments and the soils adjacent to it. The characteristics (physical, chemical and biological), and the risk fate of some heavy metals (As, B, Cr, Cu, Zn, Cd, Pb, Ni, Fe and Mn) were measured. Moreover, the risks of the studied pollutants were assessed using many indices: irrigation water quality index (IWQI), contamination factor (Cf), degree of contamination (Cd), Salinity indices and Zn equivalent (ZE). Additionally, kinetic studies of the inorganic pollutants were evaluated to determine their availability and impact on the surrounding environment.ResultsData from IQWI showed that water in all five sites was assumed to be very bad and unsuitable for usage with a general average (14.62 and 25.35) in all four seasons. ZE exceeds the critical level of 250, which means there is a risk of soil contamination.ConclusionsThe elevated levels of heavy metals, microbial enzymes, pathogenic fecal coliform and Salmonella reflect bad and direct risk of dealing with such water in irrigation and its effect on the soil ecosystem and the growing crops. Most of the tested parameters exceeded the acceptable levels of the Egyptian Governmental Law Guidelines, WHO and FAO, which may threaten aquatic life. Best managements practices and remediation techniques should be applied to minimize the hazards in such waters.

Effects of soil moisture and an AC-electric field on the phytoremediation of the Cd-contaminated soil

ABSTRACT Phytoremediation enhanced by electric field has been considered a green and low-cost technology for remediating heavy metal-contaminated soils. Soil moisture is a main environmental factor that affects Cd availability in the soil. However, the effects of soil moisture and AC-electric field on the remediation efficiency of willow (Salix spp.) and S. Alfredii interplanted together remain unclear. In the present study, we designed four treatments (60% soil field capacity, 60% soil field capacity + 0.5 V·cm−1 AC, 100% soil field capacity, 100% soil field capacity + 0.5 V·cm−1 AC) to explore the impacts of soil moisture and AC-electric field on soil Cd availability and Cd accumulation in plants. The results showed that the application of an AC-electric field significantly increased soil Cd availability by 20.9% and 10.8% under both 60% and 100% soil field capacity, respectively. Both high water with and without AC-electric field treatments reduced the proportion of acid-extractable and reducible Cd of soil but increased the proportion of residual Cd. Compared with the control, an AC-electric field with 60% soil field capacity significantly enhanced the biomass of S. Alfredii shoots by 31.2% and increased Cd accumulation in willow leaves and S. Alfredii shoots by 14.6% and 32.3%, respectively. In addition, the biomass production of willow was significantly enhanced but the uptake of Cd by willow was dramatically decreased under an AC-electric field with high water treatment. Therefore, these results suggest that the AC-electric field combined with 60% soil field capacity may be a more promising remediation technique to clean up the Cd-contaminated soil.

Role of compost in assisted phytostabilization via three naturally occurring species on mine-contaminated soil and health risk alleviation for livestock

Phytostabilization emerges as an efficient and enduring remediation technique for heavy metal-contaminated mine soils using plants acclimatized to such circumstances. In this research, the synergistic effects of Marrubium cuneatum, Verbascum speciosum, and Stipa arabica species, alongside municipal solid waste compost (MSWC) amendment at 0, 1, 3, and 5 % rates, were assessed for a six-month pot experiment aimed at remediating naturally polluted soil containing lead (Pb) and cadmium (Cd) and mitigating the health risks associated with these metal exposures for grazing ruminants. Applying compost improved the aboveground biomass of M. cuneatum and V. speciosum and S. arabica by 13, 19, and 18 %, respectively. Also, soil dehydrogenase and urease enzyme activities were enhanced up to 131 and 34 %. Upon MSWC application, all three species uptake Cd and Pb at a significantly lower rate, except in the V. speciosum shoot at 3 and 5 % doses, and bioaccumulation factors were markedly diminished. Compost notably augmented the antioxidant system, leading to a reduction in malondialdehyde content of V. speciosum, M. cuneatum, and S. arabica by 35, 29, and 23 %, respectively, and an elevation in chlorophyll level. Superoxide dismutase, catalase, glutathione peroxidase, and ascorbate peroxidase activities either increased or displayed no significant differences. Risk assessment revealed that MSWC substantially decreased the daily intake of Pb and Cd and their accumulation in animal organs, thereby eliminating limits on meat consumption. Findings affirm the combined efficacy of MSWC and the study species in stabilizing contaminated Pb and Cd soils, diminishing risks to animal feed security and human health.

Assessing soil contamination by potentially toxic elements in artisanal and small-scale gold mining sites of the Adamawa Region, Cameroon

Gold mining is acknowledged as a principal source of environmental contamination, primarily due to the release of potentially toxic elements (PTEs) through tailings dispersion into adjacent soils. Such contamination leads to land degradation, pollution, biodiversity loss and soil contamination, and subsequently impacts the food chain, human health and soil ecosystems. This study evaluates the extent of PTE contamination in soils at artisanal and small-scale gold mining (ASGM) sites within the Meiganga area of the Adamawa-Yade Domain, Cameroon. ASGM extraction processes from quartz veins in this area involve the removal of topsoil to access the ore. Comparative analysis of soil samples from three profiles within the mining zone were conducted to determine contamination levels using pollution indices: enrichment factor, geoaccumulation index, contamination factor and pollution load index. Results indicate higher concentrations of PTEs in soils from the mining area compared to the control profile, with notable contamination in the bottom slope profiles and B horizons, reflecting considerable metal accumulation. The contamination levels of PTEs substantially exceed background levels in the upper continental crust. The study attributes the elevated concentrations of PTEs not only to local mineralization but also to anthropic activities, particularly ASGM, which contributes to their enrichment, distribution and mobility. This pronounced contamination necessitates immediate intervention, advocating for pollution-control measures to address potential ecosystem and human health risks. It highlights the environmental toll of ASGM and underscores the imperative for sustainable mining practices and effective soil remediation techniques, including phytoremediation and soil replacement, to alleviate the adverse effects.

Harnessing Nature's Power to Cleanse Water Bodies through Phytoremediation of Aquatic Plants

The use of plants to remove, detoxify, or immobilize environmental contaminants, a process known as phytoremediation, is an emerging field with significant potential for the sustainable and economical treatment of polluted water bodies. Aquatic plants are uniquely suited for this purpose due to their inherent capabilities to uptake and metabolize a diverse range of pollutants such as heavy metals, pesticides, and organic compounds. Although the method does present challenges, including the length of time for effective cleanup and potential toxin bioaccumulation, innovative advancements in fields like genetic engineering and integrated remediation techniques offer promising avenues to overcome these hurdles. Additionally, the function of phytoremediation in carbon sequestration, paired with potential commercial uses, underscores its role as an essential tool for sustainable environmental stewardship. Therefore, it's crucial to continue research, encourage policy backing, and foster community participation to fully exploit the benefits of phytoremediation in aquatic settings.

Remediation and management techniques for industrial dairy wastewater and sludge: a review

Remediation and management techniques for industrial dairy wastewater and sludge: a review

Appraisal of Flat Roof Defects in Commercial Buildings and the Remediation Techniques

Appraisal of Flat Roof Defects in Commercial Buildings and the Remediation Techniques

Synergistic enhancement of cadmium immobilization and soil fertility through biochar and artificial humic acid-assisted microbial-induced calcium carbonate precipitation

Microbially induced carbonate precipitation (MICP) is emerging as a favorable alternative to traditional soil remediation techniques for heavy metals, primarily due to its environmental friendliness. However, a significant challenge in using MICP for farmland is not only to immobilize heavy metals but also to concurrently enhance soil fertility. This study explores the innovative combination of artificial humic acid (A-HA), biochar (BC), and Sporosarcina pasteurii (S. pasteurii) to mitigate the bioavailability of cadmium (Cd) in contaminated agricultural soils through MICP. X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses revealed that the integration of BC and A-HA significantly enhances Cd immobilization efficiency by co-precipitating with CaCO3. Moreover, this treatment also improved soil fertility and ecological functions, as evidenced by increases in total nitrogen (TN, 9.0–78.2 %), alkaline hydrolysis nitrogen (AN, 259.7–635.5 %), soil organic matter (SOM, 18.1–27.9 %), total organic carbon (TOC, 43.8–48.8 %), dissolved organic carbon (DOC, 36.0–88.4 %) and available potassium (AK, 176.2–193.3 %). Additionally, the relative abundance of dominant phyla such as Proteobacteria and Firmicutes significantly increased with the introduction of BC and A-HA in MICP. Consequently, the integration of BC and A-HA with MICP offers a promising solution for remediating Cd-contaminated agricultural soil and synergistically enhancing soil fertility.

Catalytic Dechlorination of Three Organochlorides by Recyclable Nano-Palladium-Engineered Natural Sponge with Formic Acid

Catalytic dechlorination of organic chlorides by palladium (Pd) with HCOOH represents one of the most effective and promising techniques for environmental remediation. In this study, we adopted alkaline-modified porous natural sponge as support of a Pd nanocatalyst (Pd@M-Sponge) and HCOOH as a hydrogen source for the hydrodechlorination of florfenicol (FF), o-chlorophenol (o-CP), and p-chlorophenol (p-CP). Favorable conversion efficiency of FF, o-CP, and p-CP was achieved at 25 °C and atmospheric pressure attributed to the small diameter and high catalytic reactivity of the prepared Pd NPs, in addition to the slight internal mass transfer limitation of the prepared Pd@M-Sponge. High reaction rate constants were obtained even in the conditions of a low molar ratio of HCOOH to p-CP (10:1) and a high concentration of p-CP (500 mg/L). The prepared catalyst also demonstrated superior recyclability without any obvious decrease in catalytic reactivity in 20 successive p-CP dechlorination cycles. This work provides an ideal recyclable and cost-effective catalyst based on renewable and biocompatible natural material for the catalytic hydrodechlorination of chlorinated organic pollutants with formic acid and a new view for the exploration and designing of highly reactive and stable catalysts for hydrodechlorination.

Highly efficient adsorption assisted photocatalytic decontamination of metronidazole by Co3O4 doped graphitic carbon nitrides

Since traditional wastewater treatment techniques only partially remove antibiotics like metronidazole (MTZ), the rising use of these drugs causes their entry into wastewater and receiving surface waterways. A flexible method that may effectively degrade such organic pollutants is adsorption assisted photocatalytic degradation. Herein, an easy mixing-and-heating procedure was used to synthesize visible light-induced g-C3N4/Co3O4 heterojunction photocatalysts. The structural properties and morphology of as-prepared materials were measured using characterization techniques such as FTIR, FSEM, and XRD analysis. The as-prepared catalyst has demonstrated a remarkable adoption and photocatalytic performance in degrading MTZ. It was found that 0.2 weight percent of Co3O4 was the optimum amount for achieving the best photocatalytic efficiency. A key factor in boosting photo-generated carrier separation is the synergistic interaction between g-C3N4 and Co3O4. The kinetics study of MTZ adsorption and degradation as well as factors effecting such as pH (2-10) and catalyst dosage process were investigated. The functional treatment method attained 78% degradation of MTZ under the following general conditions: pH = 6, g-C3N4/Co3O4 = 0.04 g/L, and reaction time = 200 min and MTZ concentration = 20 mg/L. A possible mechanism for the photocatalytic degradation was introduced, wherein O 2 • − was found to be the leading radical, whereas h + and H O • radicals contribute moderately to the degradation process. The research presents an appealing and environmentally friendly technique for the practical remediation of waste water carrying antibiotics.

The Application of Tannic Acid-Coated Magnetite Nanoparticles for Recovery of Microplastics from the Water System

The presence of microplastics (MPs) is rapidly increasing in the environment, posing a significant threat to public health and the ecosystem. To monitor the impact of MPs, it is crucial to have standardized detection methods and MPs remediation techniques. Therefore, this study aimed to use tannic acid-coated magnetite nanoparticles to recover MPs, specifically polystyrene (PS) and polyethylene terephthalate (PET), from water bodies. A facile method for MPs recovery was established using the synthesized tannic acid-coated magnetite (TA-Fe3O4) as an adsorbent. TA-Fe3O4 was synthesized using tannic acid, iron (II) sulfate heptahydrate, and iron (III) chloride hexahydrate through a one-pot co-precipitation method. The adsorbent material was then characterized using a scanning electron microscope coupled with an energy dispersive x-ray spectroscopy (SEM–EDS), x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, zeta potential, and N2 adsorption–desorption (BET) techniques, confirming its successful synthesis. The maximum adsorption efficiencies for PS and PET were 83% and 98%, respectively, under the experimental conditions of pH 6–7, a contact time of 300 min, an adsorbent dose of 2.5 g/L, and an initial MPs concentration of 1.25 g/L. The study also found that the presence of ions in wastewater had a significant effect on MP recovery. However, when it came to recovering MPs from the spent adsorbent, the maximum values were observed in an acidic medium at pH 3–4 under sonification conditions. In conclusion, TA-Fe3O4 showed potential and efficiency in the recovery of MPs in aqueous media. However, further investigation is needed to improve the method and explore its application for multi-MPs recovery performance.