Ecological Health Research Articles

A study on phytogenotoxicity induced by biogenic amines: cadaverine and putrescine.

Among the compounds present in necro-leachate, a liquid released during the process of decomposition of the human body, are the biogenic amines cadaverine and putrescine. Although some studies on necro-leachate have indicated a potential ecotoxicological and public health risk associated with it, the research on this type of contamination is still rather limited. This study presents information about the phytotoxic and cytogenotoxic potential of cadaverine and putrescine, evaluated separately and within a mixture. Phytotoxicity was evaluated through a germination test, the initial growth of seedlings with Lactuca sativa, and cytogenotoxicity through chromosomal aberration and micronucleus tests with Allium cepa. The L. sativa results showed a phytotoxic effect for the evaluated amines, by reducing root (> 90%) and hypocotyl (> 80%) elongation. The co-exposure of cadaverine and putrescine potentiated cytogenotoxic activity by aneugenic action in the meristematic cells of A. cepa. From this result, it is possible to infer the eco-toxicogenic potential of cadaverine and putrescine. This study not only highlights the importance of the phytotoxic and cytogenotoxic effects of these amines but also emphasizes the urgent need for further investigation into contamination originating from cemetery environments. By evaluating the risks associated with necro-leachate, this research is aimed at informing global efforts to protect ecological and public health.

Genetic variation in the CYP1A gene caused by laboratory exposure of benzo (a) pyrene to common carp

Polycyclic aromatic hydrocarbons (PAHs) are pervasive environmental contaminants, with benzo(a)pyrene (B(a)P) standing out as a prototypical example. B(a)P is a known mutagen and carcinogen that, upon metabolic activation stimulated by cytochromes P450 (CYP1A) with microsomal epoxide hydrolase, reacts with DNA. In this study, common carp (Cyprinus carpio) were subjected to three different doses of B(a)P (1μg/kg and 10μg/kg) to investigate the mutagenic effects on B(a)P-derived DNA in vivo.Blood samples were collected, followed by thorough DNA extraction and polymerase chain reaction analysis. The findings revealed a pronounced mutational impact of B(a)P on the amplified segment of the CYP1A gene. Specifically, at a concentration of 1μg/kg, B(a)P induced 8 mutations, 3 amino acid alterations, and the emergence of 5 new haplotype patterns. In contrast, at a concentration of 10μg/kg, B(a)P resulted in 21 mutations, 10 changes in amino acids, and the generation of 7 new haplotype patterns. Additionally, alterations in the three-dimensional protein composition were observed in both dosage groups.This study underscores the significant mutagenic potential of B(a)P, shedding light on its capacity to induce genetic changes and protein structure modifications, thereby emphasizing the importance of monitoring and addressing the environmental presence of PAHs for both ecological and human health considerations

Potential Toxic Metal Concentration and Risk Assessment in Agricultural Soil and Lentil Crop (Lens culinaris Medik) in Dawunt Woreda, Northwest Wollo, Ethiopia

Health implications for the population due to consuming contaminated crops have been a great concern worldwide. This study aimed to measure the levels of potential toxic elements in lentils and their growing soil in Dawunt Woreda, Ethiopia. Accordingly, 15 soil samples along with the lentil samples were collected to measure the level of potential toxic elements, including chromium (Cr), manganese (Mn), iron (Fe), lead (Pb), cadmium (Cd), copper (Cu), and cobalt (Co), by using an inductively coupled plasma optical emission spectrometer and for assessing the potential ecological and human health risk. The wet digestion method using aqua regia (HCl/HNO3 3 : 1) was employed for soil and lentil sample preparation. The mean concentrations of Fe, Mn, Co, Cu, Cd, Pb, and Cr in the lentil sample were 60.4, 9.68, 0.75, 5.7, 0.25, 0.9, and 1.15 mg/kg, respectively. In soil, the mean concentrations of Fe, Mn, Co, Cu, Cd, Pb, and Cr were 649, 19.9, 3.32, 40.0, 15.2, 1.83, and 69.1 mg/kg, respectively. All of the potential toxic metals in agricultural soil and lentil samples were found to be below the reference level set by the World Health Organization, except Cd, in the soil samples. Five single metal and three cumulative pollution index parameters were employed for the data and results showed that Fe, Cu, and Cr moderately pollute the soil and are highly contaminated by Cd. The cumulative pollution indices also confirmed that the extent of soil pollution varied from highly contaminated to moderate contamination. The possible health risks at various exposure routes have also been estimated. The single-metal and cumulative-metals health risks (cancer and noncancer) of adults and children due to chronic exposure to soil and consumption of lentils were estimated using the health quotient and health index values as per the United States Environmental Protection Agency guidelines. Thus, the results revealed no significant adverse health risks (cancer and noncancer) for adults and children. Therefore, the inhabitants in the study area have no significant health impacts due to either the consumption of lentil crops or exposure to agricultural soil particles.

Occurrence and Distribution of Plastispheres in Coastal Sediments and Waters along the Maharashtra Coast, India

AbstractMicroplastics can promote microbial colonisation and biofilm growth, thus being referred to as “plastispheres”. The global plastic pollution surge is likely to adversely impact ecology and human health by providing a novel habitat for microbial communities. Even though microplastics in marine environments have been the subject of in-depth research, plastispheres have recently received attention. Thus, the current study investigates the prevalence and distribution of plastispheres along the Maharashtra coast of India, considering their plausible implications for ecology and human health. Microplastics were isolated from sediment and water samples obtained from 10 sampling sites. Subsequently, these microplastic particles were subjected to ATR-FTIR and scanning electron microscopy (SEM) analyses to ascertain their chemical composition, surface topography, and presence of attached biofilms. The predominant polymers composing the microplastic particles were polypropylene (42.8%), polyethylene (28.6%), polystyrene (14.3%), and polyvinyl chloride (14.3%). SEM analysis revealed the presence of topographical structures and degradation effects, facilitating microbial attachment on the microplastic surface. About 50% of the microplastic particles tested positive for biofilms, with over 66% of those collected from Girgaon and Malvan beaches exhibiting biofilm presence. These positively screened particles also displayed comparatively rough surface structures, likely enhancing microbial colonisation. Microplastic ageing and polymer type could positively affect microbial colonisation. Diatoms and fungal hyphae exhibit varied interactions with microplastic polymers. Notably, microplastics host various reproductive stages of fungi, as evidenced by filamentous networks, mycelia, and conidiophores.

UNLOCKING THE POTENTIAL: TRANSFORMING THE GOMTI RIVER INTO A MODEL OF RIVER HEALTH

Rampant urbanization and industrialization along the river Gomti banks have led to severe degradation of its water quality and ecological health. The disposal of industrial and domestic sewage directly into the river, encroachment upon its floodplains for urban development, and ineffective waste management practices pose significant threats to its well-being. This paper examines the deteriorating condition of the Gomti River and proposes strategies for revitalizing it into a healthy river ecosystem. Drawing parallels with the Bogota River restoration project, the study identifies key challenges and opportunities for enhancing the health of the Gomti River. It suggests a holistic approach to wastewater management, including the establishment of treatment plants and the implementation of integrated waste management strategies. Additionally, the paper evaluates the impact of riverfront development projects on the rivers ecological integrity and underscores the need for sustainable urban planning practices to mitigate further degradation. By analyzing case studies and best practices from around the world, the paper provides insights into effective river restoration strategies and emphasizes the importance of community engagement and stakeholder collaboration in achieving long-term sustainability goals for the Gomti River

Pollution levels and probability risk assessment of potential toxic elements in soil of Pb-Zn smelting areas.

Soil pollution around Pb-Zn smelters has attracted widespread attention around the world. In this study, we compiled a database of eight potentially toxic elements (PTEs) Pb, Zn, Cd, As, Cr, Ni, Cu, and Mn in the soil of Pb-Zn smelting areas by screening the published research papers from 2000 to 2023. The pollution assessment and risk screening of eight PTEs were carried out by geo-accumulation index (Igeo), potential ecological risk index (PERI) and health risk assessment model, and Monte Carlo simulation employed to further evaluate the probabilistic health risks. The results suggested that the mean values of the eight PTEs all exceeded the corresponding values in the upper crust, and more than 60% of the study sites had serious Pb and Cd pollution (Igeo > 4), with Brazil, Belgium, China, France and Slovenia having higher levels of pollution than other regions. Besides, PTEs in smelting area caused serious ecological risk (PERI = 10912.12), in which Cd was the main contributor to PREI (86.02%). The average hazard index (HI) of the eight PTEs for adults and children was 7.19 and 9.73, respectively, and the average value of total carcinogenic risk (TCR) was 4.20 × 10-3 and 8.05 × 10-4, respectively. Pb and As are the main contributors to non-carcinogenic risk, while Cu and As are the main contributors to carcinogenic risk. The probability of non-carcinogenic risk in adults and children was 84.05% and 97.57%, while carcinogenic risk was 92.56% and 79.73%, respectively. In summary, there are high ecological and health risks of PTEs in the soil of Pb-Zn smelting areas, and Pb, Cd, As and Cu are the key elements that cause contamination and risk, which need to be paid attention to and controlled. This study is expected to provide guidance for soil remediation in Pb-Zn smelting areas.

Development of Macroinvertebrate Multimetric Index for Assessment of Large Rivers in Thailand.

Human activities are a significant threat to the health of river ecosystems, especially in developing countries. In Thailand, benthic macroinvertebrates have been widely used for bioassessment for aquatic ecosystem evaluation. However, most of them focuses on streams, which may not be applicable to large rivers. This study aimed to fill this gap by developing a macroinvertebrate multimetric index for Thailand's large rivers. Sampling was conducted in 15 rivers, and 41 sites across Thailand. Physico-chemical parameters, habitat characteristics, and macroinvertebrates were analyzed. Macroinvertebrate data were analyzed and metrics calculated. The seven selected core metrics, including Plecoptera taxa, EPT taxa, insect individuals %, Crustaceans and Mollusca individuals %, collector-gatherers taxa, intolerant taxa in BMWPThai, and Hilsenhoff Biotic Index, showed a strong response to anthropogenic disturbance. The final Thailand Large River Multimetric Index (TLMI) classified river health from "Excellent" to "Very Poor" condition. The validation of TLMI confirmed its ability to distinguish river health conditions. Overall, the TLMI can used as an assessing and monitoring ecological health tool for Thailand's large rivers, that can be applied for river management and conservation.

Human factors and health status of the highland forest ecosystems in North Shewa Zone, Central Ethiopia

The main purpose of this study was to evaluate anthropogenic factors and ecological health status of the forest ecosystems in the north Shewa zone (NSZ), Ethiopia. Tree cutting, grazing, cultivation, and fires were the major anthropogenic factors that led to deforestation and loss of biodiversity. The ecological analysis showed that the sites of Mehal-Wonz, Mehal-Tsebel, and Abogedam forests were very heavily disturbed, while Debdebo and Zego forests were heavily and moderately disturbed, respectively, implying the severe degradation of most forests in NSZ. Therefore, to restore the degraded forest areas of the zone, in-situ and ex-situ community-based conservation strategies were recommended.

Micro and nanoplastics pollution: A review on global concern and its impacts on ecosystems

AbstractIn recent decades, the ubiquity of micro and nanoplastics (MNPs) pollution has emerged as a global concern due to its potential risks to both ecological and human health. The detrimental effects of MNPs have resulted in significant changes in the physicochemical and biological properties of terrestrial soil and benthic sediment. These alterations have led to a disrupted nutrient cycle, potential future climate hazards, and further impacts on ecosystem services. This review aims to discuss the possible origins, composition, abundance, life cycle, and transport processes of MNPs in aquatic and terrestrial ecosystems. It seeks to understand the potential ecological and human health risks associated with MNPs pollution and explores their implications for biodiversity conservation and ecosystem services. Moreover, this review highlights the advanced analytical techniques used to detect and quantify MNPs. It further suggests policy frameworks to combat this pollution in natural environments. The findings of this review are intended to assist environmentalists, microbiologists, hydrologists, and policymakers in identifying scientific gaps and pragmatic solutions to reduce MNPs pollution. Future research should investigate the intake mechanism and impact of MNPs on plants in different ecosystems, as well as their effects on food chains and human health. This will ensure that the ecological and human health risks associated with MNPs pollution can be timely mitigated.

LEGAL FRAMEWORKS FOR FACING ENVIRONMENTAL POLLUTION CRIMES: A COMPARATIVE STUDY OF JORDANIAN LEGISLATION AND INTERNATIONAL AGREEMENTS

Objectives: The objective of this study is to conduct a comprehensive analysis of legal frameworks, both domestically and internationally, concerning environmental pollution. By examining these frameworks, the study aims to understand how they address the multifaceted problem of environmental pollution and identify potential solutions. This research holds significance in the context of increasing environmental degradation worldwide.
  
 Methods: To achieve the stated objective, this study employs a multidisciplinary approach. It involves a thorough review and analysis of domestic legislation related to environmental protection in various jurisdictions. Additionally, international treaties, agreements, and conventions addressing environmental pollution are examined. Furthermore, scholarly literature and legal documents pertaining to environmental law and policy are reviewed to provide a comprehensive understanding of the subject matter.
  
 Results: The findings from this research provide valuable insights into the strengths and weaknesses of existing legal frameworks for addressing environmental pollution. Analysis of domestic legislation reveals variations in approaches to environmental protection across different jurisdictions. Similarly, examination of international agreements highlights the importance of cooperation and coordination in addressing transboundary environmental issues. The discussion of findings will address the practical implications for policymakers, legal professionals, and environmental organizations, with a focus on identifying strategies to strengthen legal mechanisms for combating environmental pollution.
  
 Conclusion: In conclusion, this study underscores the critical role of legal frameworks in addressing environmental pollution at both domestic and international levels. By providing a comprehensive analysis of existing legal mechanisms, this research contributes to broader efforts aimed at mitigating environmental degradation and promoting sustainable development. Moving forward, it is essential for policymakers, legal professionals, and stakeholders to collaborate effectively to strengthen and enforce environmental laws, ensuring the protection of ecological systems, public health, and social well-being.

Theory-driven design of phosphazene-based porous polymer beads for enhanced iodine adsorption

Efficient adsorbents for radioiodine removal play a crucial role in safeguarding public and ecology health. However, conventional trial-and-error approaches for designing such high-performance adsorbents suffer from limited efficiencies. Herein, we employed a rational design strategy guided by precise density functional theory (DFT) calculations to synthesize a polyphosphazene-based microsphere tailored for iodine capture. Theoretical calculations quantifying the interactions of iodine molecules with diverse nitrogen-containing organic groups reveal the superior affinity of phosphazene groups with I2. Motivated by these findings, we judiciously designed a poly(bis(diethylamino)) phosphazene (PDEP) with a high density of active adsorption sites. Subsequently, PDEP was integrated into a composite bead with polyether sulfone (denote as PDEP@PES) for practical applications. PDEP@PES exhibits an elevated static adsorption capacity of 1.08 g/g, surpassing the majority of reported beads. More importantly, under a high flow rate of 200 mL/min, the dynamic uptake amount of PDEP@PES reaches 78.8 mg/g, outperforming pristine PES beads (3.19 mg/g) and commercial silver-impregnated silica gel (23.0 mg/g). The XPS results confirm the formation of robust charge-transfer complex between phosphazene groups with I2. This was further supported by their substantial interaction energy of -20.59 kcal/mol, as determined by DFT calculations. Our study demonstrates the high feasibility of polyphosphazene-based microspheres for radioiodine removal, shedding light on the enormous potential of theory-driven design paradigm for the development of exceptional adsorbents for environmental remediation.

Roles of extracellular polymeric substances in arsenic accumulation and detoxification by cell wall intact and mutant strains of Chlamydomonas reinhardtii

Arsenic (As) pollution seriously threatens human and ecological health. Microalgal cell wall and extracellular polymeric substances (EPS) are known to interact with As, but their roles in the As resistance, accumulation and speciation in microalgae remain unclear. Here, we used two strains of Chlamydomonas reinhardtii, namely CC-125 (wild type) and CC-503 (cell wall-deficient mutant), to examine the algal growth, EPS synthesis, As adsorption, absorption and transformation under 10–1000 µg/L As(III) and As(V) treatments for 96 h. In both strains, the As absorption increased after the EPS removal, but the growth, As adsorption, and transformation of C. reinhardtii declined. The CC-125 strain was more tolerant to As stress and more efficient in EPS production, As accumulation, and redox transformation than CC-503, irrespective of EPS presence or absence. Three-dimension excitation-emission matrix (3D-EEM) and attenuated total reflectance infrared spectroscopy (ATR-IR) analyses showed that As was bound with functional groups in the EPS and cell wall, such as -COOH, -NH and -OH in proteins, polysaccharides and amino acids. Together, this study demonstrated that EPS and cell wall acted as barriers to lower the As uptake by C. reinhardtii. However, the cell wall mutant strain was more susceptible to As toxicity due to lower EPS induction and higher As absorption.

Iron bioaccumulation and ecological implications in the coastal swamp wetlands ecosystem of South Kalimantan: Insights from giant mudskipper fish as bioindicators

This study investigated iron (Fe) accumulation in South Kalimantan's coastal swamp wetlands ecosystem, utilizing giant mudskipper fish as indicators of heavy metal pollution. By analyzing Fe levels in water, sediment, and fish organs over time, insights into its effects on the environment and human health were gained. Furthermore, through Atomic Absorption Spectrometry, Fe concentrations in Kuala Lupak's coastal wetland were measured, revealing significant correlations between Fe levels in water, sediment, and fish tissues. These results enhance our understanding and inform better management strategies. Anthropogenic and natural sources contribute to the accumulation of heavy metals, particularly Fe, with anthropogenic pollution being the most dominant. This study presented the escalating concentrations of Fe within the Kuala Lupak estuary and raised concerns regarding the ecological and human health implications. Continuous monitoring, source identification, public awareness, regulations, remediation, and long-term exploration are essential for addressing heavy metal pollution and its ecological impact. Therefore, valuable insights are provided for environmental management and conservation efforts.

Pollution Characteristics and Ecological and Human Health Risk Assessment of Toxic Elements in Fallout Dusts of Ma'an District Schools

The main goals of this paper were to (i) analyze the fallout dust deposits collected from 16 schools in the Ma’an district in Jordan and study their pollution characteristics and (ii) assess the ecological and human health risk of potentially toxic elements (PTEs) exposure to these dusts. Elemental and mineralogy analyses were conducted using X-ray fluorescence and diffraction techniques. The most abundant major elements in the dust were Ca, Si, Fe and Al, while the main minerals were carbonate and silicate indicating the detrital sedimentary origin of the dust. The pollution level was assessed using the enrichment factor, contamination factor, geo-accumulation index, the Nemerow integrated pollution index and pollution load index, which were in the order of Zn>Pb>Cu>Cr>V>Mn=Fe. The potential ecological risk results showed a very low ecological risk. For children and adults, both carcinogenic and non-carcinogenic health risks related to ingestion, dermal contact and inhalation of fallout dust were assessed.

In-situ construction of 1D β-FeOOH nanobelts/2D porous g-C3N4 heterojunction for enhanced “signal-on” photoelectrochemical aptasensing

Bisphenol A (BPA), a prevalent organic pollutant found in wastewater environment, is notorious for its resistance to natural degradation, raising significant ecological and human health concerns. In this study, a “signal-on” photoelectrochemical aptasensing system was designed for detecting BPA in real water samples with high specificity and sensitivity. One-dimensional (1D) β-FeOOH nanobelts were synthesized on a two-dimensional (2D) porous carbon nitride (g-C3N4) through an in-situ growth procedure. The β-FeOOH/g-C3N4 nanocomposites demonstrated superior photoelectric conversion efficiency due to several factors: (i) The 1D nanobelt-like structure of β-FeOOH shortens the charge transfer path within the nanocomposite, enabling directional and rapid migration of photoinduced charges from the interior to the surface. (ii) β-FeOOH possesses strong visible absorption capabilities, enhancing the utilization of g-C3N4 under photoexcitation, resulting in the generation of numerous photo-induced carriers. (iii) The in-situ formation of the β-FeOOH/g-C3N4 heterojunction establishes an intimate interfacial contact, facilitating the rapid separation and transfer of charges between β-FeOOH and g-C3N4. A photoelectrochemical aptasensing platform based on the photoactive material of β-FeOOH/g-C3N4 detects BPA with reduced photocurrent owing to the presence of BPA-aptamer macromolecules on the electrode surface. This BPA detection system exhibits excellent linearity over a wide concentration range from 10 pM to 10nM, with high sensitivity (a detection limit of 3.5 pM), stability, specificity, and repeatability. Furthermore, this research offers a straightforward and rapid sensing platform for monitoring BPA enriched water environments.

Mobile phone-assisted imprinted nanozyme for bicolor colorimetric visual detection of erythromycin in river water and milk samples

The residues of erythromycin (ERY) may have negative impacts on the ecological environment, health, and food safety. How to detect ERY effectively and visually is a challenging issue. Herein, we synthesized a molecularly imprinted polymer based nanozymes for selective detection of erythromycin (ERY-MIPNs) at neutral pH, and developed a mobile phone-assisted bicolor colorimetric detection system. This system produced a wide range of color changes from blue to pinkish purple as the ERY concentration increased, making it easy to capture the visualization result. Also, the system showed good sensitivity to ERY ranging from 15 to 135 μM, with a detection limit of 1.78 μM. In addition, the system worked well in the detection of ERY in river water and milk, with the recoveries of 95.57% ~ 103.20%. These data suggests that this strategy is of considerable potential for practical applications and it provides a new idea for visual detection with portable measurement.

Prediction of microbial activity and abundance using interpretable machine learning models in the hyporheic zone of effluent-dominated receiving rivers

Serving as a vital linkage between surface water and groundwater, the hyporheic zone (HZ) plays a fundamental role in improving water quality and maintaining ecological security. In arid or semi-arid areas, effluent discharge from wastewater treatment facilities could occupy a predominant proportion of the total base flow of receiving rivers. Nonetheless the relationship between microbial activity, abundance and environmental factors in the HZ of effluent-receiving rivers appear to be rarely addressed. In this study, a spatiotemporal field study was performed in two representative effluent-dominated receiving rivers in Xi'an, China. Land use data, physical and chemical water quality parameters of surface and subsurface water were used as predictive variables, while the microbial respiratory electron transport system activity (ETSA), the Chao1 and Shannon index of total microbial community, as well as the Chao1 and Shannon index of denitrifying bacteria community were used as response variables, while ETSA was used as response variables indicating ecological processes and Shannon and Chao1 were utilized as parameters indicating microbial diversity. Two machine learning models were utilized to provide evidence-based information on how environmental factors interact and drive microbial activity and abundance in the HZ at variable depths. The models with Chao1 and Shannon as response variables exhibited excellent predictive performances (R2: 0.754–0.81 and 0.783–0.839). Dissolved organic nitrogen (DON) was the most important factor affecting the microbial functions, and an obvious threshold value of ∼2 mg/L was observed. Credible predictions of models with Chao1 and Shannon index of denitrifying bacteria community as response variables were detected (R2: 0.484–0.624 and 0.567–0.638), with soluble reactive phosphorus (SRP) being the key influencing factor. Fe (Ⅱ) was favorable in predicting denitrifying bacteria community. The ESTA model highlighted the importance of total nitrogen in the ecological health monitoring in HZ. These findings provide novel insights in predicting microbial activity and abundance in highly-impacted areas such as the HZ of effluent-dominated receiving rivers.

Ecological restoration trajectory of the Taitema Lake wetland in arid northwest China: A 36-year wetland health assessment using Landsat time series data

The Taitema Lake wetland in the lower reaches of the Tarim River (northwest China) is sensitive to hydrological changes and provides necessary ecosystem functions for biodiversity conservation. Monitoring and evaluating the long-term dynamics of the Taitema Lake wetland is essential for conserving and restoring regional wetland ecosystems. This paper used a dense time series of Landsat images from 1986 to 2021 to map the Taitema Lake wetlands. It analyzed the annual and seasonal variations of the wetlands by ten ecological indicators, which include area extent, vegetation, hydrology, and landscape features. A systematic assessment of the ecological quality of the wetlands over the past 36 years, along with their influencing factors, was conducted from the perspective of wetland health. The results showed that (1) the recovered water areas and the wetlands showed a clear trend of ecological restoration since 2000, accompanied by an increased fragmentation. The total wetland area increased from 69.95 km2 in 1986 to 1164.47 km2 in 2021, with a 15.6-fold increase, and the vegetation area increased twentyfold to 639.84 km2. (2) The wetness in the core zone increased consistently across seasons, coupled with a simultaneous vegetation expansion surrounding the core zone. The areas with increasing wetness levels account for 48 % during winter and spring, and the areas with vegetation expansion account for 81 % and 72 % in summer and autumn, respectively. (3) The wetland ecological health status recovered to a “Good” level in 2021 and has not reached the “Excellent” status. The expansion of the water body is the primary driver behind the promotion of wetland ecological recovery. Small water bodies within the area range of 0.05 to 0.1 km2 notably exhibited the most stimulating effects on the wetlands. Thus, increasing the count of smaller water bodies helps rehabilitate vegetation growth and mitigating the water supply’s stress to sustain large lacustrine bodies.

Modelling Mercury Dynamics in Soils Impacted by Mercury Emission from Artisanal and Small-Scale Mining Activities

ABSTRACT Soil systems are commonly regarded as receptors of anthropogenic mercury contamination and play an essential role in the containment or dispersion of pollution to surface water, groundwater and the atmosphere. Mercury fate and transport are simulated using a local scale model to evaluate mercury dynamics in a soil system impacted by anthropogenic mercury pollution from artisanal and small-scale gold mining. The model assumes first-order differential equations that describe losses principally by evasion and leaching simulated on a yearly time step from thirty years ago to the present and into the future, where two different scenarios are considered. The model predicts that topsoil mercury concentrations may more than double in the next 50 years. Soil mercury is currently a source of mercury to the atmosphere and water but the leaching flux is less than the evasion flux. The soil would accumulate mercury until emission is curtailed and may require more than 500 years for levels to decrease to background values. If current emission rates are maintained, mercury contents of contaminated soil will keep increasing and will reach levels that poses risk to ecological and human health.

Physico-chemical assessment of surface water from mining activities in Maiganga coal mine, Gombe state, Nigeria

Purpose. Surface water from mining activities may undergo various physico-chemical changes that can impact its quality and ecological health. This study conducted a comprehensive physico-chemical assessment of surface water affected by mining operations, with a particular emphasis on heavy metal content. Methods. These parameters were chosen due to their importance as indicators of water quality and potential contamination. Water samples were collected from different locations within and around Maiganga Coal mine area and analyzed using standard laboratory techniques. The assessment included the measurement of physico-chemical parameters such as temperature, total dissolved solids and concentrations of heavy metals such as chromium, lead, manganese, cadmium and copper. Also, cations and anions such as calcium, magnesium, sodium, potassium, nitrate, chloride sulfate and fluoride that can impact water quality were considered. Findings. The results of the physico-chemical assessment revealed substantial variations of chromium (0.00-0.03 mg/l), lead (0.00-0.05 mg/l), manganese (0.00-12.11 mg/l), cadmium (0.10-0.14 mg/l) and copper (0.00-1.02 mg/l) concentrations. Also, cations and anions such as calcium (0.00-1.13 mg/l), magnesium (11.90-30.07 mg/l), sodium (0.20-1.11 mg/l), potassium (0.10-0.66 mg/l), nitrate (3.90-4.78 mg/l), chloride (84.0-319.0 mg/l), sulphate (8.0-240.0 mg/l) and fluoride (0.00-0.89 mg/l) can impact water quality levels across the sampled surface water bodies. Originality. Evidence of acid mine drainage, caused by mine effluents that are limited to surface water and do not reach groundwater, has been found through analysis of data from wells, ponds, and streams. Practical implications. These variations obtained could be attributed to the discharge of acidic or alkaline substances associated with coal mining activities.