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1

Aluminum contamination in the Carrizal River sub-basin and its impact on the water purification process and public health

Parrales Meredith Maribel Macías, López Joseph Manuel Ostaiza, Villafuerte Carlos Ricardo Delgado, Macías Fabian Fabricio Peñarrieta

Journal of Ecological Engineering

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2025

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Vol. 26, nr 2

183--189

EN

The objective of the research was to analyze aluminum contamination in the water purification process of the Carrizal River sub-basin and the Municipal Joint Drinking Water Company (EMMAP-EP) of the Tosagua canton, with an exploratory-descriptive approach and eight sampling points were established, aluminum was analyzed in sediments, sludge, and water at different stages of the purification process. the ICP-OES method was used to determine the concentrations of aluminum. Then the mass balance of this element was carried out. The results showed aluminum concentrations at different stages of the process, with the highest concentration in the settling of sludge for both sediments (10902.93 mg/kg) and water (0.896 mg/L). In comparison, the reservoir and the river presented similar concentrations for sediments (9329.75 mg/kg and 9344.46 mg/kg) and water (0.736 mg/L and 0.662 mg/L). While in the distribution networks, a concentration of less than 0.17 mg/L was evidenced, which is below the limits proposed by the WHO and the EPA, while the mass balance revealed a net accumulation of 42.16 g/day of aluminum, indicating that the system retains this element.

2

Analysis of sediment’s quality of the Oława River in Poland using indices of heavy metals and statistical techniques

Hołtra Anna, Zamorska-Wojdyła Dorota, Ferenc Zbigniew

Environment Protection Engineering

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2025

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Vol. 51, nr 2

105--117

EN

This case study reports a dataset enabling the analysis of heavy metal concentrations in sediments collected in the Oława River basin. The focus is on the ecological risk associated with six metals: copper (Cu), zinc (Zn), lead (Pb), chromium (Cr), nickel (Ni), and cadmium (Cd). The key information on the pollution status of the aquatic environment is provided by the single- (EF, Igeo, and PI) and the multi-elemental (PLI, PINem, RI, and MERMQ) pollution indices, and statistical techniques such as Spearman’s correlation, the principal component analysis, and the cluster analysis. The sediments indicate the presence of Cu, Zn, Pb, and Ni, a smaller input of Cr, and the absence of Cd, according to criteria from the State Working Group on Water in Germany (the LAWA’s guidelines) and pollution indices. As assessed by the RI index and the sediment quality guidelines (the SQGs), the potential ecological risk is possible to occur at some sampling points as a result of uncontrolled emission of pollutants. This resource supports environmental monitoring, risk management, and comparative re-search of aquatic environments.

3

Detection of Some Heavy Metals Used in the Surface Soil (Sediments) from Khirbet Al-Samra in Jordan

Alkhawaldeh Ahmad Khalf, Natsheh Iyad Y., Alsaleh Majd M., Shatnawi Mohamad, Shahrour Wesam, Majdalawi Majdi M., Alsarhan Ali Ata

Journal of Ecological Engineering

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2024

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Vol. 25, nr 8

160--167

EN

Spatial analysis was used to analyze the environmental quality of soil in the Al-Zarqa region in order to identify sources and estimate heavy metal concentrations, which aided in the assessment of soil quality and heavy metal pollution. The primary goal of this study was to assess the environmental impact of heavy metal pollutants in the Al-Zarqa region. To assess pollution levels, the concentrations of Cu, Mn, Cd, and Pb were measured in surface soil (sediment) samples collected from Khirbet al-Samra. A total of sixteen samples were analyzed. The elevated levels of Cu and Cd are primarily attributed to various sources such as the weathering of nearby rock formations and the release of agricultural waste materials. An evaluation of sediment contamination was conducted using pollution indicators including Geo-accumulation index (Igeo), enrichment factor (EF), and pollution load index (PLI). Spatial distribution analysis was used to determine the distribution pattern of each metal. The results revealed that metal concentrations (Cu, Pb, and Mn) are higher, while Cd concentrations are lower than the maximum allowed limits. The results from the EF analysis indicated elevated concentrations of Cu and Cd in the sampled area. In terms of the Igeo analysis of Khirbet al-Samra sediments, it was found that the concentrations of Pb, Cu, and Mn are within safe levels and relatively unaffected by human activities, whereas the concentrations of Cd exceed the mean values, suggesting a higher level of contamination specifically for cadmium. The potential sources of heavy metals in the investigated area were identified using factor analysis, and the geographical distribution of heavy metals was shown using spatial distribution. The examination of correlation coefficients revealed diverse relationships between the different parameters, depending on the source of input for each metal.

4

Why is navigation difficult on the lower Vistula River?

Magnuszewski Artur

Gospodarka Wodna

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2024

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Nr 6

26--32

EN

The lower Vistula River natural conditions limit the possibilities of river regulation. River regulation works performed at the end of the 19th c. did not take into account the massive transport of bed load that, in a wet year, can reach 1.5x106 tons of material. During low river stage periods, sandbars appear, forcing the river to strongly meander. The movement of sandbars was analysed based on the Sentinel-2 satellite images. The comparison of sandbars distribution on 04/09/2016 and 30/07/2017 indicated an average shift of 443 m. Sonar measurements performed in that period show that, during one year, the thalweg changes its position moving from one bank to another. In places where the thalweg alternates between the banks, the river depth over sandbars falls below 1 m.

PL

Naturalne warunki dolnej Wisły stanowią ograniczenie dla regulacji rzeki. Wykonane w końcu XIX w. prace regulacyjne nie uwzględniały ogromnych mas rumowiska wleczonego, którego transport w warunkach roku mokrego może sięgać 1.5x106 t. Przy niskich stanach wody na powierzchni pojawiają się piaszczyste ławice, które wymuszają kręty układ nurtu. Do badania ruchu ławic wykorzystano analizę obrazów satelitarnych Sentinel-2. Porównanie położenia ławic na obrazach z 2016-09-04 i 2017-07-30 wykazało ich przesunięcie o średnio 433 m. Wykonane w tych latach pomiary echosondą pokazują, że w ciągu jednego roku nurt zmienia położenie, przemieszczając się spod jednego brzegu na przeciwległy brzeg. W miejscach, gdzie nurt przerzuca się między brzegami, głębokości nad ławicami spadają poniżej 1 m.

5

Spatial Distribution, Ecological Risk and Analysis of Sources of Trace Metal Elements in Surface Sediments of Pond Thomas (Brenne), France

Haouchine Amina, Nedjai Rachid, Motelica-Heino Mikael, Erdmann Saskia, Nemer Zoubida

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 8

194--206

EN

This study aims to contribute to understanding the processes influencing the spatial distributions of trace metal elements in surface sediments of Brenne’s ponds (France) and assess potential pollution levels in the area. It was motivated by the lack of knowledge regarding the hydrogeochemical dynamics of limnic entities, which are ponds. To achieve this, 25 sediment samples were collected from Pond Thomas, considered as a ‘sentinel pond’, and underwent analysis for grain size, total organic carbon (TOC) concentrations, and trace metal elements (TMEs) (specifically Cu, Ni, Pb, As, Zn, Cr, and Cd). The results revealed that trace metal elements are primarily concentrated in two areas: the northwest section and the upstream region in the southern part of the pond. Applying various pollution indicators such as the enrichment factor (EF), geo-accumulation index (Igeo), and potential ecological risk index (RI), it was found that Pb and As are the most enriched elements, with respective EFs of 3.5 and 4.9. Their average concentrations exceed geochemical background values by 4 and 5.68 times in certain samples. The sediments in the southern part of the pond showed moderate contamination levels for As and Pb, with moderate to severe pollution (2 < Igeo < 3), reaching a maximum Igeo of 2.26 for As. Although the RI values across the pond are relatively low, Cd and As still pose moderate potential ecological risks. Additionally, principal component analysis and Pearson correlation analysis indicated two sources of TMEs in the area: Zn, As, Ni, Cd, Pb, and Cr are primarily from natural sources, while Cu appears to have a local anthropogenic origin.

6

Geochemical Analysis of Coastal Sediments near Larache and Moulay Bousselham, Morocco

El Idrissi Soukaina, Labriki Allal, Sadiki Mohamed, Akhlidej Nouhaila, Bounouira Hamid, Said Sanaa, Amsil Hamid, Didi Abdessamad, Aarab Iliasse, Chakiri Said

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 8

221--231

EN

The aim of this study is to identify the main pollutants and evaluate the mechanisms of sediment transport from land to sea. This goal is justified by environmental pollution in the area associated with dredging and port activities. The objective is planned to be achieved by investigating the geochemical behavior of major and trace elements in fourteen surface sediment samples collected along the Moroccan Atlantic coast, from the mouth of the Lukkous River to the coast between the cities of Larache and Moulay Bousselam. k0-standardization method of neutron activation analysis using neutrons of the Moroccan Triga Mark II research reactor at the National Centre for Nuclear Energy, Science and Technology, has been used for analysis of collected sediment samples. The enrichment factor analysis revealed high levels of arsenic and chlorine, along with significant calcium enrichment, were found along the Atlantic coast. The enrichment factors (FE) for arsenic and chlorine are in the range of 20 < FE < 40, and for calcium, the FE is in the range of 5 < FE < 20. Conversely, some elements exhibited little to no enrichment, suggesting a crustal origin. PCA helped in synthesizing these findings, providing a clearer understanding of the spatial variations in sediment composition based on their multi-elemental signatures. The research examines surface sediments along the Moroccan Atlantic coast, revealing current contamination levels and geochemical behavior. These findings, applicable to similar coastal environments, are crucial for monitoring and managing sediment quality, especially in areas affected by erosion. Additionally, dredging and port activities in this region significantly disturb the sediments, resuspending contaminants and altering sediment composition, which further exacerbates pollution issues. This study offers a comprehensive geochemical characterization of coastal sediments in Morocco, enhancing understanding of sediment contamination and geochemical processes, with implications for environmental protection and sustainable marine resource management.

7

Assessment of Acid Mine Drainage’s Impact on Makhat’s Watershed Plants (Taza Province, Morocco)

Lahmidi Ikram, Assabar Narmine, Mesrar Laila, Laaraj Marouane, Jabrane Raouf

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 8

261--270

EN

The mining production industry often leaves large quantities of mine spoil heaps exposed on the surface. The lack of monitoring of these discharges could create sources of pollution; the most common among them is acid mine drainage, which causes the contamination of the environment by heavy metals present in its solutions. Bouaazza’s mine, present in Taza province North-East Morocco, was known for lead and sulfide exploitation for many years, which contributed to the exposure of important quantities of acid spoil heaps on the surface. To assess the impact caused by acid mine drainage in Makhat’s stream plants, sediments, and plant samples were collected along the stream. Physicochemical results for sediments showed pH values below 6. Geochemical results for sediments indicated Pb concentrations higher than the World Surface Rock Average standards (16 ppm), with values over 3000 ppm. As for plants, the values found after ICP-AES analyses were higher than the WHO permissible limit (2 ppm). These results confirm the harmful impact of the lack of environmental monitoring while and after abandoning mining explorations, which leads to environmental disasters.

8

Radioactive elements detected in crude oil from volcanic areas

Radulescu Renata, Stoianovic Doru, Chis Timur

Nafta-Gaz

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2023

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R. 79, nr 12

755--763

EN

In the geological structures containing crude oil and associated gases and located in areas where volcanic activity has been detected, radioactive substances and minerals are contained both in the structure of the reservoir waters and in the impurities related to the composition of the extracted crude oil. They are present during the extraction of crude oil and associated gases and affect human health and environmental safety. Radioactive elements have been detected in reservoir waters, in impurities associated with crude oil, and especially during the processing of drilling fluids (the separation of detritus sourced from geological strata from the used drilling fluid). Other radioactive elements were also detected in the areas polluted with oil and drilling waste. In order to determine the radioactivity level of crude oil originating from the area of volcanic activity of the Romanian Mountains, crude oil samples were collected from the oil field in a one-year analysis. The collected samples were analysed to determine their physical-chemical structure. The reservoir water associated with these samples and the minerals separated from the crude oil following their solvent extraction were also analysed. Radioactive elements were detected using X-ray spectrometry, and their chemical structures are also discussed.

PL

W strukturach geologicznych zawierających ropę naftową i towarzyszący jej gaz ziemny oraz zlokalizowanych w obszarach, w których wykryto aktywność wulkaniczną, substancje i minerały radioaktywne zawarte są zarówno w strukturze wód złożowych, jak również w zanieczyszczeniach powiązanych ze składem wydobywanej ropy. Są one obecne podczas wydobycia ropy naftowej i towarzyszącego jej gazu, mając wpływ na zdrowie ludzkie i bezpieczeństwo środowiska. Pierwiastki radioaktywne wykryto nie tylko w wodach złożowych i związanych z nią zanieczyszczeniach, ale przede wszystkim podczas obróbki płuczek wiertniczych, w tym w procesie oddzielania detrytusu pochodzącego z warstw skalnych od zużytej płuczki wiertniczej. Inne pierwiastki radioaktywne wykryto także w obszarach zanieczyszczonych ropą i odpadami wiertniczymi. Dla określenia poziomu radioaktywności ropy naftowej pochodzącej z obszaru aktywności wulkanicznej w górach Rumunii, z jednego ze złóż ropnych w ciągu jednego roku pobrano próbki ropy naftowej do analiz. Pobrane próbki przeanalizowano pod kątem struktury fizykochemicznej. Przebadano także wodę złożową powiązaną z tymi próbkami oraz minerały oddzielone z ropy naftowej po ich ekstrakcji rozpuszczalnikiem. Pierwiastki radioaktywne zidentyfikowano za pomocą spektrometrii rentgenowskiej, omówiono również ich struktury chemiczne.

9

Application of the QuEChERS Method for the Analysis of Contamination by Pesticide Residues in the Sediments of Three Moroccan Lagoons

Fegrouche Rachida, Dahak Hicham, El Kamli Taha, Oussekour Mohammed, Zaza Saida, Ben Salem Abdelkrim, Benyacoub Badreddine

Journal of Ecological Engineering

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2023

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Vol. 24, nr 12

336--345

EN

Agricultural, industrial, and domestic activities are major contributors to the contamination of natural environments. The aim of this study is to assess the level of sediment contamination by organic pollutants in three Moroccan lagoons: Moulay Bousselham, Oualidia, and Khnifiss. samples were analyzed using liquid chromatography (LC) coupled with mass spectrometry (MS) in Multiple Reaction Monitoring (MRM) mode to detect organophosphorus, carbamate, urea and its derivatives, and other chemical groups. Gas chromatography (GC) coupled with mass spectrometry (MS) was also used to analyze organochlorines. The samples were subjected to dispersive solid-phase extraction (dSPE) using QuEChERS before analysis. Fifteen active substances were detected, including organochlorines, organophosphates, carbamates, ureas, pyrethroids, and others. Three active substances, known for their high toxicity in aquatic environments (carbendazim, malathion, and chlorpyrifos), were identified. The heptachlor molecule (organochlorine family), although banned in Morocco, was still detected in the sediments of the lagoons of Oualidia and Khenifiss. Given the potential harm that these pesticides can cause to living organisms, it is crucial to introduce new crop protection techniques to address this issue.

10

Detrital zircon populations in Ediacaran Period sediments distinguish active from passive continent margins even when metamorphosed and help resolve the Gondwana-Panotia supercontinent/megacontinent argument

Crow Michael, Zaw Khin, Thu Kyaw, Belousov Ivan, Goemann Karsten

Geotourism / Geoturystyka

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2023

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nr 1-2 (72-73)

16--17

EN

Great thicknesses of sand and greywacke were deposited on the margins of megacontinents during the Ediacaran Period (620–542 Ma). Zircon age populations in sediments with long deep-time flat profiles distinguish passive margin sedimentation from shorter humped zircon profiles characteristic of sediments derived from volcanic arcs and their feeder zones in active margins. An example of a single hump detrital profile is given by an Ediacaran Period volcano present in the Charnian Supergroup in the Anglo-Brabant Massif of the East Avalonia terrane. This Gondwana fragment was originally part of the West Africa craton and was subsequently accreted to Laurentia. A volcanic complex with sediments carrying an Ediacaran biota is overlain by Triassic sediments. The main phase of eruption at c. 561 Ma provides a single hump zircon age histogram with a few pre-eruption zircon xenocrysts up to 40 Ma older

11

Using GPS and Run-Off Rates Data to Study the Close Monitoring Networks for Dams – Al-Kut Barrages as a Case Study

Saiwan Malik Khalaf, Hamdoon Rana Mozahim, Al-Zuhairy Mudhaffar Sadiq

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 2

87--93

EN

The dams and barrages are among the most important engineering structures for water supply, flood control, agriculture, and electric power generation. Monitoring the horizontal and vertical deformation of the barrage’s body and identifying the risk it’s so important to maintain the dam and also to reduce costs. Where in this research the case of the Al-Kut barrage is studied by observing the body of the barrage using surveying devices through (GPS) by taking spatial observations of the two networks of stations, the horizontal and vertical networks. Then compare them with the observations of previous years to determine the magnitude of the deformation through the differences between the observations. By calculating the differences and finding the displacement of surveying observations from 2014 to 2021, It was found that the highest and least displacements in the horizontal stations is 50 and 11 mm, respectively. Also, for the vertical network observations, the highest and lowest differences in elevation were 11and 3 mm, respectively. Where, the results showed a slight deformation within the acceptable limits. In addition, the annual and monthly discharge rates for a number of years were evaluated to observe the extent of the impact of run-off rates on increasing sedimentation at the upstream of Al-Kut barrage. It was found that the accumulation of sediment on the river’s left bank affected the gates’ efficiency and put pressure on the other gates, which led to some operational issues in the barrage gates.

12

Ecological assessment of heavy metals accumulation in sediments and leaves of Avicennia marina along the Diu coast of the northeast Arabian Sea

Patale Varsha, Tank Jigna G.

Oceanologia

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2022

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No. 64 (2)

276--286

EN

The Coastal region of Diu is the natural habitat dominated by Avicennia marina mangrove species at the southeast coast of Saurashtra in Gujarat state of India. However, Diu being a famous industrial and tourism place survival of these mangrove species is threatened due to anthropogenic activities. In present studies, sediment and leaf samples of A. marina were collected from the Diu coast to evaluate the ecological threat of heavy metals accumulation in the marine habitat. There was remarkable presence of heavy metals such as copper, nickel, cadmium, chromium and lead in sediments and leaf samples of A. marina. The values of Biological concentration factors (BCFs) of heavy metals in leaf samples were high for cadmium, chromium and lead which suggest chelation of these heavy metals with biomolecules. The geo-accumulation index suggested that Site-4 and Site-5 were heavily contaminated with copper and nickel. The ecological risk index suggested that there is no significant effect of heavy metals on growth of plants in the mangrove ecosystem. Principal component analysis revealed that the samples collected from the natural habitats (Site-4 and Site-5) near the fishing and industrial areas were the main sources of heavy metal contamination. Hence, it was concluded that the concentration of heavy metals in the studied ecosystem had limited impact on growth of plants at Site-1, Site-2 and Site-3. However, growth of plants at Site-4 and Site-5 were threatened due to the toxic effect of copper and nickel present in its sediments.

13

Distribution and ecological risk evaluation of bioavailable phosphorus in sediments of El Temsah Lake, Suez Canal

Younis Alla M., Soliman Naglaa Farag, Elkady Eman M., Mohamedein Lamiaa I.

Oceanologia

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2022

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No. 64 (2)

287--298

EN

Phosphorus reactivity and bioavailability in lake sediments is determined by diverse fractions of phosphorus (P) and their distribution. To gain deeper insights into P dynamics in Lakes, sediments from El Temsah Lake were investigated for water soluble P (WSP), readily desorbable P (RDP), algal available P (AAP) and Olsen-P using different chemical extraction methods. Total P (TP), organic P (OP), inorganic P (IP) contents, were also investigated. The TP, OP and IP concentrations in the sediments were 598.39 µg/g, 199.76 µg/g and 398.63 µg/g, correspondingly. Concentrations of the bioavailable P in the sediments followed the order AAP (48.42 µg/g)>WSP (14.60 µg/g)>RDP (1.82 µg/g)>Olsen-P (1.50 µg/g). Pearson correlation analysis exposed that there were significant correlations among the bioavailable P fractions concentrations and the TP concentrations (r=0.83; p>0.01, r=0.94; p>0.01, r=0.62; p>0.05); for WSP, AAP, and Olsen-P respectively. Moreover, there were no obvious associations amongst total P and N, Al, Ca, Fe, Mg, Mn, and OM in the sediments. The outcomes of phosphorus ecological risk assessment in sediments by single pollution standard index method revealed that the standard index of TP varied from 0.19 to 1.85. It demonstrated that the ecological pollution risks of phosphorus in El Temsah Lake sediments was comparatively low.

14

Coastal cliff erosion as a source of toxic, essential and nonessential metals in the marine environment

Bełdowska Magdalena, Bełdowski Jacek, Kwasigroch Urszula, Szubska Marta, Jędruch Agnieszka

Oceanologia

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2022

|

No. 64 (4)

553--566

EN

Due to the rising environmental awareness, emissions and releases of pollutants, including metals, have been considerably reduced in the last decades. Therefore, the remobilization of natural and anthropogenic contaminants is gaining importance in their biogeochemical cycle. In the marine coastal zone, this process occurs during the erosion of a shore, especially the most vulnerable cliffs. The research was conducted in the Gulf of Gdańsk (southern Baltic Sea) from 2016 to 2017. The sediment cores were collected from four cliffs; additionally, marine surface sediments were also taken. The concentrations of essential (Cr, Mn, Fr, Cu, Zn) and nonessential (Rb, Sr, Y, Zr, Ba) metals were analyzed using the XRF technique. The levels of the analyzed metals were relatively low, typical of nonpolluted areas. However, considering the mass of eroded sediments, the annual load of metals introduced into the sea in this way is significant. In the case of Cu, Zn, and Y the load can amount to a few kilograms, for Cr and Rb – over ten kilograms, for Mn, Sr, and Zr – several tens of kilograms, for toxic Ba – over 100 kg, and in the case of Fe – 4.8 tonnes. During strong winds and storms, when the upper part of a cliff is eroded, especially the load of Zn and Cr entering the sea may increase. The content of Cr, Zr, and Ba in the cliffs was higher compared to marine sediments from the deep accumulation bottom, which indicates that coastal erosion may be an important source of these metals.

15

Leaching of heavy metals from contaminated soil stabilised by Portland cement and slag Bremen

Lindh Per, Lemenkova Polina

Ecological Chemistry and Engineering. S

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2022

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Vol. 29, nr 4

537--552

EN

Leaching behaviour is an important evidence of soil quality. The assessment of leaching of heavy metals from the contaminated soil is vital for environmental applications. However, leaching may differ in soil stabilised by various ratios of binders. In this study we measured leaching behaviour of soil contaminated by As, Cd, Co, Cr, Cu, Hg, Ni, Pb, V, Zn, methyl Hg, aliphatic compounds of hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and dissolved organic carbon (DOC). To evaluate leaching of these substances we tested the effects of changed amount of binder (120 kg and 150 kg) and binder ratios (70/30 %, 50/50 % and 30/70 %) added to soil samples. Soil was dredged from several stations in Ostrand area, SCA Sundsvall Ortvikens Pappersbruk. The results demonstrated a systematically decreasing leaching with the increased slag. The contribution of this research include: (i) devising systematic approach to extract information on leaching from stabilised soil collected from the coastal area of Bothnian Bay, (ii) developing a workflow for stabilising soils by various combination of Portland cement Basement CEM II/A-V (SS EN 197-1) and ground granulated blast furnace slag (GGBFS), Bremen type (SS EN 15167-1), (iii) determining water ratio and density for the untreated and stabilised soil and performing comparative analysis, (iv) evaluating chemical content of pollutants and toxic elements in the aggregated soil samples. Treatment of the contaminated soil by binders improved its parameters by the increased strength and decreased leaching of heavy metals and toxic elements.

16

Monitoring the Evolution of Redox Changes in Sediments made Possible by Electrochemical Multilayer Probes

Popa Radu, Moga Ioana Corina, Nealson Kenneth H., Cimpoiasu V.M.

Archives of Metallurgy and Materials

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2022

|

Vol. 67, iss. 3

1037--1041

EN

Marine sediments with rapid oxic/anoxic transitions are difficult to monitor in real time. Organic overload that may lead to anoxia and buildup of hydrogen sulfide can be caused by a variety of factors such as sewage spills, harbor water stagnation, algal blooms and the vicinity of aquaculture operations. We have tested a novel multiprobe technology (named SPEAR) on marine sediments to evaluate its performance in monitoring sediments and overlaying water. Our results show the ability of the SPEAR probes to distinguish electrochemical changes at 2-3 mm scale and at hourly cycles. SPEAR probes have the ability to identify redox interfaces and redox transition zones in sediments, but do not use micromanipulators (which are cumbersome in field and underwater applications). We propose that the best target habitats for SPEAR-type monitoring are rapidly evolving muddy deposits and sediments near aquaculture operations where pollution with organics stresses the ecosystem.

17

Constraints of the MAX4781 CMOS Solution for Electrode Switching in Multilayer Electrochemical Probes

Cimpoiasu V.M., Radulescu F., Nealson K.H., Moga Ioana Corina, Popa R.

Archives of Metallurgy and Materials

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2022

|

Vol. 67, iss. 2

691--694

EN

The most common means to analyze redox gradients in sediments is by push/pulling electrochemical probes through sediment’ strata while repeating measurements. Yet, as electrodes move up and down they disrupt the texture of the sediment layers thus biasing subsequent measurements. This makes it difficult to obtain reproducible measurements or to study the evolution of electrochemical gradients. One solution for solving this problem is to eliminate actuators and electrode movements altogether, while instead deploying probes with numerous electrodes positioned at various depths in the sediment. This mode of operation requires electrode switching. We discuss an electrode-switching solution for multi-electrode probes, based on Complementary Metal-Oxide-Semiconductor (CMOS) multiplexors. In this solution, electrodes can be individually activated in any order, sequence or time frame through digital software commands. We discuss constraints of CMOS-based multilayer electrochemical probes during cyclic voltammetry.

18

Characteristics of morphodynamic conditions in the shallows of Puck Bay (southern Baltic Sea)

Szymczak Ewa, Rucińska Maria

Oceanological and Hydrobiological Studies

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2021

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Vol. 50, No. 2

220--231

EN

Puck Bay is an unusual and thus interesting coastal water region, as it combines two different environments – a lagoon and the sea. They differ from each other in their seabed morphology, salinity, dynamics and water exchange. Their common elements are the extensive shallows and the vicinity of the Hel Peninsula. The shallows of Puck Bay have developed at various stages of its evolution, which began several thousand years ago and continues to this day. They have been shaped by varying morphogenetic factors resulting from changes in sea level and accompanying evolution phases of sand barriers, e.g. washover fans, as well as the intensity and directions of sediment transport. At present, the shallows cover more than 35% of the seabed area and are influenced by hydrodynamic factors and availability of sediments. The study area was divided into five fields, taking into account morphological and genetic criteria as well as recent hydrodynamic conditions. This study provides an updated map with classification and distribution of surface sediments and describes grain size parameters for sediment samples collected in the selected fields. Based on a comprehensive assessment of grain size parameters, lithodynamic equilibrium zones were determined and areas of sediment deposition and redeposition were identified.

19

Extraction and application of bottom sediments in a closed cycle

Mazur Kamila, Eymontt Andrzej, Wierzbicki Krzysztof

Journal of Water and Land Development

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2021

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no. 51

265--271

EN

Human activities in relation to aquatic ecosystems result in significant economic losses in the form of contamination of water sources, deteriorating its quality and therefore its availability in lakes, water bodies and even in soil. Hence the need for systematic revitalisation or reclamation of water ecosystems. Such actions, in order to be rational, require a detailed understanding of the causes, and then the use of appropriate technology. The need for the above-mentioned actions result from the weather changes that have been noticeable in recent years, as well as environmental pollutants increasing water eutrophication in reservoirs and stimulating the development of some species of cyanobacteria. These cyanobacteria can cause serious water poisoning, especially in water supply systems. Therefore, a rational, comprehensive technology for the removal of bottom sediments and their processing into organic and mineral fertiliser has been developed with properties similar to manure. It also creates opportunities to improve the structure of soils thanks to the supply of organic carbon, the loss of which was found, among others, in also in soils of Poland and EU. These new possibilities of revitalisation hitherto unknown make it possible to a large extent, compliance with environmental requirements when revitalising water reservoirs and soil.

20

Heavy metals and 137Cs levels in macrophytes and temporal distribution in sediments : application for estuarine environment status assessment (Vistula Lagoon – southern Baltic)

Zalewska Tamara, Brzeska-Roszczyk Paulina, Danowska Beata, Pełechaty Mariusz

Oceanological and Hydrobiological Studies

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2020

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Vol. 49, No. 1

68--80

EN

The paper presents the first data on the concentrations of heavy metals (Cd, Pb, Zn, Cu, Ni, Cr, Mn) and 137Cs and their contamination ratios (CR) in the most abundant species of macrophytes in the Vistula Lagoon. No significant differences in the concentrations of heavy metals and 137Cs between macrophyte taxa or the influence of rivers flowing into the Vistula Lagoon on heavy metal concentrations in the area were found. The concentrations of heavy metals in macrophyte taxa varied in the following ranges: Cd – 0.1–0.7 mg kg−1 d.w.; Pb – 0.5–5.0 mg kg−1 d.w.; Zn – 29–390 mg kg−1 d.w.; Cu – 2.5–8.3 mg kg−1 d.w.; Ni – 0.4–6.8 mg kg−1 d.w.; Cr – 0.5–2.8 mg kg−1 d.w.; Mn – 380–8500 mg kg−1 d.w. Since the 1990s, a decline or stable state of heavy metal concentrations in bottom sediments has been observed, reflecting changes in the environment of the Vistula Lagoon. The linear sedimentation rate in the Vistula Lagoon was 3.3 mm y−1. The results presented in the paper can serve as a baseline for assessing changes in the environmental status of the Vistula Lagoon, which may occur as a result of future investments, including building a new navigable canal through the Vistula Spit.