No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Benthic foraminifera and trace metal distribution: a case study from the Burullus Lagoon, Egypt
Abstract
Benthic foraminifera are widely used to detect the health of their habitat, where they are very sensitive to even slight variations in the ecosystem. Therefore, the main objectives of this study are to examine the benthic foraminiferal assemblages in the sediments of Burullus Lagoon, evaluate the pollution levels and deduce the impact of trace metals on foraminifera. The continuous discharge of trace metals from agricultural, industrial and domestic sources into the lagoon may lead to a severe environmental problem. The concentrations of Mn, Cu, Cd, Zn and Pb within the sediments were measured. Recently, the assessment of contamination is principally based on the contamination indices which provide fast and simple quantitative values on the degree of pollution in a given aquatic environment. Thus, some indices, including the contamination factor, the degree of contamination, pollution load index, geoaccumulation index, ecological risk factor and potential ecological risk index are applied in this investigation. Based on the contamination factors, the sediments are very highly contaminated with Cd, considerably to very highly contaminated with Cu and Zn, moderately contaminated with Mn, low to moderately contaminated with Pb. All sites display very high values for the degree of contamination. Moreover, the values of the pollution load index are higher than 1, indicating that the lagoon is polluted. Depending on the geoaccumulation index, the contaminants are arranged as follows Cd > Zn > Cu > Mn > Pb. It is clear that Cd is the main contributor to the ecological risk factor in Burullus Lagoon. Concerning the richness of the foraminiferal assemblages, it fluctuates between 1–5 species per sample. Because of its higher tolerance to extreme conditions (changes in salinity and pollution), Ammonia tepida is the most abundant species. The occurrence of rare living individuals (25) is restricted only to sites close to El-Boughaz Inlet where higher salinity and lower levels of pollution are recorded. The same trend of distribution is shown by Cribroelphidium excavatum and miliolids, where they occur at sites with higher salinities. The occurrence of test deformities in all the studied sites may be related to the response of benthic foraminifera to trace metal. The forms of deformation include spiroconvex, reduced chambers, twisted tests, twinning, additional chamber and complex forms. The deformation depends on the nature of pollutants. Twinning and reduced chambers are the most dominant forms in areas close to the agricultural drainage (southern drains), while complex forms are abundant in areas close to industrial drainage (El-Gharbia drain). Thus, salinity and pollution may be the most regulatory factors controlling the distribution of foraminifera. This investigation confirmed the role of benthic foraminifera as a good ecological indicator in Burullus Lagoon.
... Moreover, the PTEs concentrations in the ORE are comparable to other similar environments around the world ( Table 4). The Burullus Lagoon (Egypt) sediments recorded higher Cu, Zn and Cd than in the ORE [57]. Martins et al. [8] documented similar PTEs concentrations from the Guanabara Bay sediments except for Ni and Co which are extremely lower than concentrations from the ORE. ...
... (10.25%), respectively (Fig. S3). According to FMI, Haynesina depressula, Cibicides sp. and Ammonia tepida had the largest deformation percentage in overall abundance, indicating that they were the most vulnerable species to environmental changes (El-Kahawy et al., 2018;El Baz and Khalil, 2018;Price et al., 2019). ...
Benthic foraminifera are increasingly used as an indicator of environmental disturbance. Their sensitivities to pollutants can be reflected by changes in assemblage, which can provide useful information about ecosystem health. This study aimed to investigate the impact of organic and inorganic pollutants on the benthic ecology of the Chennai coast, with a focus on the 2017 oil spill caused by the collision of two ships. Sediment samples collected from five distinct zones along the coast were analysed for pollutants such as polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPH), heavy metals (Cr, Cd, Pb) and total organic carbon (TOC). Concentrations of Cr (137 μg/g), Cd (6.93 μg/g) and Pb (34.2 μg/g), as well as TPH (84.3 μg/g) and PAHs (227 ng/g), were observed. A total of 47 species of foraminifera were identified in this study, of which 12 were morphologically abnormal. In the low-impact zone, the species diversity index (H') was higher. TPH and PAH concentrations were positively associated with abnormal species. Pollution-resistant foraminifera species include Ammonia tepida, Elphidium discoidale, and Quinqueloculina lamarckiana, while opportunistic foraminifera include Pararotalia curryi, Nonionella stella, Rosalina globularis, and Spirillina vivipara. PAHs and heavy metals were adversely correlated with foraminiferal abundance, while TPH was positively correlated. To assess the response of the benthic ecosystem to hydrocarbon pollution, indices such as the Foraminiferal Index of Environmental Impact (FIEI), Exponential (H`bc) index and the Foraminiferal Abnormality Index (FAI) were used as environmental health proxies. FIEI, exp(H`bc) and FAI values show the impact of hydrocarbon pollution to an extent along the northern Chennai coast.
... Several workers have reported the influence of PTEs on the distribution and diversity of benthic foraminifera especially in estuarine-lagoon environments (e.g., [2,38,[50][51][52]). However, the concept of using total and bioavailable PTE concentrations does not directly apply when used as an assessment of the ecological response of benthic foraminifera to pollutants [1,37,53]. ...
Citation: Fajemila, O.T.; Martínez-Colón, M.; Sariaslan, N.; Council, I.S.; Kolawole, T.O.; Langer, M.R. Contamination Levels of Potentially Toxic Elements and Foraminiferal Distribution Patterns in Lagos Lagoon: A Correlation Analysis. Water 2022, 14, 37.
... The average annual water discharge from drains and Brimbal canal is 3.77 Â 10 6 m 3 and 1.94 Â 10 6 m 3 , respectively [15]. It is very important to note that the annual fish production form Lake Burulus is about 63,000 tons, which is about 42% of the fish production from the Egyptian lakes [10]. In addition, it is an important station for birds in their migration trip from Europe. ...
Lake Burullus, the second largest coastal lake and wetland in Egypt, is suffering environmentally and economically under the tremendous pressure of rapid urbanization and increase of agriculture, aquaculture and industrial activities for more than 4 decades. This caused significant reduction of the lake’s area and sever degradation of its ecological system, including the decrease in fishing yield, which consequently led to serious socio-economic challenges for the local fisheries communities as well as affecting the national fish production of Egypt. Recently, the Egyptian Government has made great efforts for the rehabilitation and restoration of the northern lakes and wetlands in attempt to improve their environmental conditions and restore their economic value. Among these efforts is Burullus Lake Rehabilitation Project, which has started in 2018 covering the inlet and the eastern part of the lake and aims to improve the water quality and fish production in the lake mainly by enhancing water exchange between the lake and the sea through dredging and side protection works. The current study provides an update of the water quality conditions over Burullus lake by carrying out a wide water sampling program that covers the entire perimeter of the lake with an emphasis on the most problematic areas. The main water quality parameters were measured and analyzed spatially in order to provide a quantitative assessment of the efficiency of the implemented rehabilitation and restoration works and provide recommendation for further improvement works. The results show that there was a significant improvement of investigated water quality parameters over the lake inlet and the eastern part where the dredging works were carried out while less improvement was found over the western part. This indicates that water exchange with the sea and the circulation pattern in the lake have the most significant influence on the lake’s water quality, which should be considered in future rehabilitation projects.
Foraminifera are unicellular heterotrophic protists that are valuable palaeoindicators in geology. This paper
evaluates the importance of the recent foraminifera as proxies of the Holocene paleoenvironmental changes
in the Adriatic Sea. The study was conducted in the Prokljan Lake (Krka River estuary). The analyzed
sediment core is 5.3 m long and over 9.600 years old. The foraminifera assemblages were used for
paleoenvironmental assessment and the obtained data were supplemented with radiocarbon isotope dating,
organic C/N, and grain size analyses. According to the results, the core can be divided into 3 zones. The
first zone, in the basal part of the core, is dominated by Ammonia tepida and it suggests the existence of a
brackish environment with limited marine influence. The second zone is a transitional zone, with a decrease
in the abundance of Ammonia tepida and stronger marine influence. Finally, the third zone has typical
marine species with the dominance of Haynesina sp. This research demonstrated that foraminifera are
important proxies of paleoenvironmental changes. Detailed reconstructions of paleoenvironments along the
eastern coast of the Adriatic are still scarce. Therefore, this work will significantly contribute to a better
understanding of the changes that occurred during the Holocene in the investigated area.
The concentrations of certain heavy metals (Cd, Co, Cr, Cu, Fe,
Mn, Ni, Pd and Zn) in the total and labile fractions of muddy
sediment samples collected from eleven sites in Lake Burullus in
January 2003 were investigated in order to evaluate the pollution
status of the Lake. The metal contents were determined by means of Atomic Absorption Spectrophotometer (AAS) using MESS-2 certified reference material (National Research Council of Canada). The average concentrations of the heavy metals analyzed in total sediment fractions exhibited the following decreasing order: Fe > Mn > Cu > Ni > Zn > Cr > Pb > Co > Cd, while the average concentrations of the heavy metals analyzed in the labile fraction followed the order: Fe > Mn > Cu > Ni > Pb > Zn > Co > Cr > Cd. The concentrations of all studied heavy metals ranged between the Effect Range-Low (ERL) and the Effect Range-Median (ERM) for most studied locations. Metal pollution index (MPI) shows very high values for both total and labile fractions at all the examined locations. Field observation reveals that Lake Burullus received industrial, agricultural and domestic sewage, suggesting that anthropogenic input is the main source of heavy metal contamination. Health hazard calculations for the contaminated sediments exhibited a possibility of health risk due to long-term exposure of the human to the polluted sediments of Lake Burullus.
The Karnafully is one of the most important rivers due to its profound influence on water chemistry and sediment characteristics. The present study intended to assess the quality of water and sediment from intertidal zone of this river in respect to the pollution index. Seasonal water and sediment samples were collected during four seasons (Monsoon, post-monsoon, winter, and pre-monsoon) of 2014. The result indicates that these investigated parameters ranged as water temperature (21.7-36 °C), pH (8.0-8.7), salinity (2.4-8.8‰), total suspended solid (0.08-0.8 g/L), dissolve oxygen (0.00-4.52 mg/L), soil temperature (21.3-33 °C), pH (5.0-6.8), sand (4.13-44.10%), silt (39.93-75.89%), clay (11.98-21.19%), soil organic matter (4.33-6.21%), organic carbon (2.5-3.6%), nitrite-nitrogen (0.69-3.97 μg/L), and phosphate-phosphorus (0.23-3.44 μg/L). Multivariate statistical analyses like post-hoc LSD test, Cluster Analysis (CA), and Principal Component analysis (PCA) brought out the spatial and temporal changing pattern of water chemistry and sediment characteristics with the effect of uprising pollution. CA ascertained the compatibility among different parameters and categorized the monitoring sites into highly and moderately polluted areas. Moreover, PCA brought out five primary components and highlighted the three dormant factors, enormously regulating the river water chemistry such as municipal waste, carbon based nitrogenous compound, and local geomorphological weathering process. This investigation provided an outline on deterioration of water and sediment quality by high anthropogenic impact and suggests national policy maker to take some initiatives for retaining the quality water and sediment properties.
Keywords: cluster analysis, intertidal zone, pollution index, principal component analysis, spatio-temporal variation.
The concentration of selected trace metals (Fe, Cd, Cu, Pb, and Zn) in 30 surface sediments were measured using Atomic Absorption Spectrometer to investigate the spatial and seasonal variations of trace metals along Kanyakumari coast, India. To assess the environmental risk of trace metals, enrichment factor, geo-accumulation index, pollution load index, and ecological risk index have been calculated. According to the pollution load index and geo-accumulation index (Igeo) values, Kanyakumari coastal sediments were unpolluted by Fe, Cu, Pb, and Zn, whereas moderately polluted by Cd with low to moderate ecological risk. The existence of the high hydrodynamic condition during the southwest monsoon is more favorable to the transport of sediments and enhance the accumulation of metals, whereas during the northeast monsoon the accumulation of metals is less. The baseline data for spatial distribution and seasonal variation of trace metals and their controlling factors found in this study will be useful for pollution monitoring program along the Kanyakumari coast.
Burullus Lake is one of most important lakes in north Delta of Egypt. It is exposed to huge amounts of serious pollutants especially heavy metals. The sediments within the lake aid in the dispersion of these metals. The main objectives of this research were to evaluate and map the spatial distribution of heavy metals in Burullus Lake sediments. Accordingly, 37 locations were randomly distributed within the lake. Sediment samples were taken from these locations. These samples were analyzed for seven metals including Fe, Cu, Zn, Cr, Co, Cd and Pb. Also, five indices were used to identify the status of metal pollutants in the Lake. These indices are: enrichment factor (EF), contamination factor (CF), degree of contamination (DC), pollution load index (PLI) and geo-accumulation index (Igeo). Ordinary Kriging was used to interpolate the spatial distribution of the studied elements within the lake. The obtained results indicated that cadmium was the most enriched element in the lake sediments due to industrial and agricultural wastes drained into the lake. The Igeo index revealed that Cd and Pb were the common pollutants in lake sediments. The DC values ranged between low (near El-Boughaz) and moderate (near drainage areas). The spatial distribution of pollutants within the lake indicated that the highly polluted areas are located close to the drains, whereas as the less polluted areas were close to El-Boughaz.
A detailed study of foraminiferal populations was carried out at three contaminated sites along the Mediterranean coast of Israel. The unpolluted coast of Nitzanim provided the first natural base line to be determined for the region. At Palmahim (domestic sewage) the species diversity and population density was greatest. Here the largest foraminiferal test sizes and the highest percentage of agglutinated foraminifera were found. In contrast, the lowest species diversity and population density occurred near the Hadera power station, where coal was the major source of pollution in the sediment. Part of Haifa Bay is currently being contaminated by a variety of heavy metals. Benthic foraminifera have been demonstrated to be sensitive in situ monitors or coastal pollution. -from Authors
The purpose of the present study is to assess the level and distribution of Mg, Co, Cu, Cd, U, Sr, Zn, As, V, Pb, Ti, Mn, Ba, Ce, Ni, P, Cr, Zr, Hf and Fe in coastal sediments of Abu Khashaba beach, Rosetta area, Egyptian Mediterranean coast. The level of pollution was evaluated using enrichment factor, geoaccumulation index and contamination factor. The results indicated that Abu Khashaba coastal sediments were extremely enriched and very strongly polluted with Cd; severely enriched and strongly polluted with As and Pb, and moderately severely enriched and polluted with Ni, Co, Sr and Ce. The highest Fe, Ba, Ce, Ni, Pb, V, Zn, Sr, Co, Cd, U, Cu, Hf, Cr and Zr were recorded along the shoreline. Fe, Mn, Pb, Co, Cd, Cu and Cr values in the Abu Khashaba coastal sediments were much higher than those recorded in the coastal sediments of the Gulf of Aqaba, the Red Sea, the Arabian Gulf and the Daliao River System of China. The enrichment of Cd, As, Pb, Ce, Ni in the sediments could be partially attributed to anthropogenic inputs and also to other already existing naturally occurring metals.
Coastal lagoons are well investigated areas because of their economical and ecological importance. Pulicat Lagoon system which is a store house of all resources is under great threat following the anthropogenic pollution. This complex lagoon ecosystem's surface area is about 500 sq.kms. In spite of the System's conservation statutes its structure has been degenerating rapidly because of pressures fishing, tourism and agricultural activities. Fishing production of Pulicat Lagoon System is approximately 52 tons/ha/year. Although a serious fishery pressure has been determined in the area, according to mortality rate and age compositions, it has been found that the growth of marine life in the environment is in unhealthy condition. The date show that land based and atmospheric sources account about two-thirds of the total impact of contaminants in to the marine lagoon constituting 44 % and 33 % respectively. A total of 30 sediment samples were collected with in the depth zone of 5 fathoms from the lagoon. The study yielded 50 benthic foraminiferal species belongs to 24 genera, 16familys, 8 super families and 3 sub-orders. Variations are also reflected on the foraminiferal test morphology, diversity and distribution. A high percentage of foraminifers almost exclusively Ammonia have da maged shells with a few channels to entire whorl missing. The phenomenon is stress response to the anthropogenic pollution. The Ammonia-Elphidium assemblage is dominant in all stations followed by Spiroloculina -Bolivina assemblage.Suggestions for development of the lagoon management and maximum sustainable marine life production have been offered by determining the present lagoon management and some a biotic characteristics of this ecosystem. Many studies assume or conclude that foraminiferal assemblages and the frequency of deformed tests are proxy indicators of pollution, but others present confounding results. Under studying the complexity of anthropogenic pollution, coastal waters and sediment is critical to the design and interpretation of meaningful studies.
In addition to physicochemical methods, benthic foraminifera have become an essential tool for the assessment of polluted environments. The main objectives of the present work were to study the distribution of benthic foraminifera along the coastline of Skhira and Gabes (southern coast of Gulf of Gabes) and to predict the impact of pollution on these organisms. Thirty-one samples were studied and a polluted area was delimited by chemical analysis, where heavy metal, fluoride, phosphorus, nitrogen, and COT contents are very high. Thirty-four species of benthic foraminifera were identified and their response to pollution is very remarkable, in which their distribution shows barren area, corresponding to the highly polluted area. Away from the contaminated area, the density and the diversity of these organisms increase. Statistical analyses (principal component analysis (PCA)/FA and matrix correlation) show a possible control of these pollutants on biotic indices (with negative correlation), in addition to the presence of tolerant and sensitive species to pollution. A variety of test malformations were noticed especially in Ammonia beccarii, Peneroplis planatus, Sorites variabilis, and Adelosina pulchella. Unpolluted stations were dominated by species characteristic of shallow water environments with sandy sediment such Ammonia parkinsoniana, Triloculina trigonula, Quinqueloculina agglutinans, and P. planatus.
Abstract
Background and aim: Mediterranean Sea, Egypt is an economically important marine environment. During the last decades there has been extensive increase in the levels of urbanization and industrialization along its coastal area.
Therefore, the present work attempts to determine the status of heavy metals distribution in sediment samples, and
their ecological risk assessment in the studied area.
Materials and methods:
Twenty surfacial sediment samples were collected from different selected stations along
the Egyptian Mediterranean Sea. The samples were homogenized and placed into sealed polyethylene bags, carried to the laboratory in an ice box and stored at −20 °C in the dark until analysis.
Results:
The results revealed that Fe had the highest mean value (243–38045 μgg−1) followed byMn (17–1086 μgg−1), and a lower concentrations were found for Co (0.43–26.39 μgg−1) and Cd (0.04–0.47 μgg−1). Risk assessment showed that Cd had the highest ecological risk (Er = 21.52), followed by Pb (Er = 3.01), while Zn had the lowest risk (Er = 0.23). Both the ecotoxicological index method and the potential ecological risk index (RI) suggested that the combined ecological risk of the studied metals may be low. Multivariate statistical analysis (Cluster and Factor analysis) suggested
that the lithogenic factor dominants the distribution of most part of the considered metals in the study area.
Conclusion: Multivariate analysis has been proved to be an effective tool for providing suggestive information regarding heavy metal sources and pathways. The results of this study provide valuable information about metal contamination in sediments along the Mediterranean Sea for over than 1200 km.
Keywords: Heavy metals, Potential Ecological risk index, Sediments, Mediterranean coast, Egypt
Contamination with heavy metals is one of the most serious problems in the aquatic environments.
In Egypt, Manzala Lake is suffering from this problem. The objective of this work was to assess
heavy metals pollutants and their spatial distribution in Manzala Lake using GIS technique. Georeferenced
water and sediment samples were randomly collected from the lake. The detected
heavy metals were: Fe, Pb, Cu, Cd, Cr, Zn and Co. The obtained results indicated that the highest
concentrations of heavy metals were observed in the northeastern and the southern parts of the
lake nearby drains. This could be attributed to industrial, agricultural and municipal wastes coming
through the drains especially Bahr El-Baqar drain and the industrial wastes coming from Port
Said drains. From the geo-accumulation index, it was noticed that the lake is more polluted with
cadmium and lead in the hydrosoils samples. All metals in water are within the EPA standard limit
except for cadmium. Geostatistics provides effective methods to quantify the contaminated waters
and sediments which support decision-making about redevelopment scenarios or remediation
techniques.
A five-step sequential extraction technique, following Tessier's protocol, has been applied to determine the chemical association of Cd, Cu, Fe, Pb, and Zn with major sedimentary phases (exchangeable, carbonate, manganese and iron oxides, organic and residual fraction) in surface sediments from 14 stations off the Libyan Mediterranean coast. This study is a first approach of chemical fractionation of these metals in one of the most economically important area of the Libyan coastline in Mediterranean Sea. The total metal content was also determined. The total concentration of metals ranged from 5-10.5 mg/kg for Cd, 9.1-22.7 mg/kg for Cu, 141.8-1056.8 mg/kg for Fe, 18.9-56.9 mg/kg for Pb, and 11.6-30.5 mg/kg for Zn. The results of the partitioning study showed that the residual form was the dominant fraction of the selected metals among most of the studied locations. The degree of surface sediment contamination was computed for risk assessment code (RAC), individual contamination factor (ICF), and Global contamination factor (GCF). Risk assessment code classification showed that the relative amounts of easily dissolved phase of trace metals in the sediments are in the order of Pb>Zn>Cd>Cu>Fe. The results of ICF and GCF showed that Sirt and Abu Kammashand had higher GCF than other sites indicating higher environmental risk. In terms of ICF value, a decrease order in environmental risk by trace metals was Pb>Zn>Cu>Cd>Fe. Therefore, Pb had highest risk to water body.
The heavy metal concentrations (Al, Fe, Ti, Mn, Zn, Cd, Co, Cr, Ni, Pb, and Cu) in sediment samples collected from the Moroccan Mediterranean coast were studied. The heavy metals concentrations obtained were similar or relatively low compared with other Mediterranean zones. To assess their distribution and distinguish between their natural and anthropogenic sources, the enrichment factor (EF) index was applied. Consequently, minor enrichment by Cd, Cu, Fe, Mn and Pb was observed. The effects on aquatic organisms were established using sediment quality guidelines (SQGs). As a result, Cu concentrations were above the interim sediment quality guidelines (ISQG), Ni and Pb presented concentrations upper the effects range-low (ERL) while Cr was above the probable effect level (PEL) in some sampling points.
In addition, a principal component analysis was performed showing that the distribution of metals in the study area seems to be influenced by both natural and anthropogenic sources. Nevertheless, the analysis of mineralogical composition has allowed the identification of a natural source as the most probable origin of some elements, such as Ni and Mn, related mainly to the geological background. In contrast, Fe, Cr, Co and Pb could be related to both natural and anthropogenic activities in the area while the Cd and Cu seem to have an anthropic origin.
Both cores reveal an upward transition from a moderately polluted environment represented by a Verneuilina media assemblage to an extremely polluted environment represented by an Eggerelloides scabrus assemblage. This faunal change may result from an increased competitiveness of some shallow water species in deeper water areas exposed to environmental stress, at the expense of more normal marine forms which have stricter ecological requirements. -from Author
This study investigates issues related to hydrodynamics in Lake El-Burullus and flow patterns therein. Burullus Lake is the second largest lake in the northern Egyptian coast with a total area of 410 km 2. It was utilized Delft3D-flow module to develop a field validated hydrodynamic model. The shallow brackish Lake is mainly affected by uncontrolled creeping of development areas and growing inflow of untreated agricultural, municipal and industrial drainage water. The developed model was used to examine a potential mitigation alternative by decreasing the pollutant loads that enter the Lake i.e. diversion of existing drains. In this fashion the creation of a new development area nearby may be feasible. In addition, the effects of hydrodynamics on pollutant dispersion either from an individual drain or all drains together. The results of this study will be the base for the water quality modeling stage. Actually, this work is the first stage of an integrated Lake management. The study concluded that the developed model efficiently simulated the hydrodynamics of the Lake which can act as an effective decision support tool for improving the environmental conditions in the surroundings.
Trace metals concentrations in sediments from the Egyptian Mediterranean coast were determined to evaluate the levels of contamination. The highest concentrations of metals were generally found in the middle region of the coast. Sediment pollution assessment was carried out using Enrichment Factor (EF), Geoaccumulation Factor (Igeo), Contamination Factor (CF), Modified Degree of Contamination (mCd), and Pollution Load Index (PLI). Association of adverse effects to aquatic life was determined using the classification of sediments according to three sets of sediment quality guidelines. The mean EF values were found to fall in the following sequence: Cr > Pb > Ni > Zn > Cu > Mn. The results demonstrated that the EF of metals in the sediments of the middle region was lower than those recorded in the western region and Rafah Station at the eastern region; the difference in the EF levels was significantly correlated with Fe concentrations along the study area. Based on the average Igeo of target elements, the Egyptian Mediterranean coast could be considered not polluted with Cr, Cu, Mn, Ni, Pb, and Zn (Igeo ≤ 0). The modified degree of contamination was >1.5, indicating zero to very low contamination. The calculated PLI were less than 1, indicating only baseline levels of pollution. There were small differences between the results obtained with the three used SQGs. Highly significant correlations were found between the concentrations of Fe, Mn, Co, Cr, and Ni, suggesting similar sources and/or similar geochemical processes controlling the occurrence of these metals in the sediments.
Concentrations of major constituents (Na, K, Ca, Mg, CO3-2, SiO3-2) and some metals (Fe, Al, Mn, Sn, Zn, V, Cu, Pb, As, Cd and Se) in surface sediments from Abu-Qir Bay and the Eastern Harbour of Alexandria were investigated. Assessment of pollution was performed using several pollution indices. The adverse effects on aquatic organisms were determined by classifying the sediments according to sediment quality guidelines. Enrichment factors (EFs) revealed anthropogenic sources for Sn and Cd in Abu-Qir Bay; while in the Eastern Harbour Sn and Cd possessed high EF values (>30). High contamination factor (CF) for Sn and Cu (>6) was obtained. Concentrations of Sn and Se in sediments of most studied sites can regularly and occasionally affect sediment-dwelling organisms. Low concentrations of Se strongly affect the variance in surface sediment composition in both studied areas. Pollution load index (PLI) indicated that most stations in both areas are polluted.
The geographic distribution of Ammonia extends from the Faeroe Islands to South Africa, throughout the Mediterrranenan and the Indian Ocean, around Australia and New Zealand as far as 45°50′S. In the western Atlantic, Ammonia extends from Miramichi Bay, Nova Scotia to Isla de los Estados, Tierra del Fuego, Argentina. The northernmost Pacific occurrences are Samish Bay, Washington on the E and Hokkaido, Japan on the W. These distributions are controlled by the latitudes (and protected waters) where the temperature reaches 17-22°C at least one month during the year. This temperature range is the minimum reproductive temperature of Ammonia. -from Authors
A study of heavy metals in estuarine sediments and foraminifera1 tests along with foraminifera1 distributions from Southampton Water indicates that: a) heavy metals have a marked effect upon foraminiferid distribution. Some species are able to tolerate pollution and their relative abundance increases at discharge points, whereas other species develop test deformities. Investigation of cores show that no deformed specimens exist within sediments prior to the introduction of pollution. b) deformed specimens contain higher levels of elements such as Cu and Zn than non-deformed specimens. This indicates that heavy metals may be responsible for the abnormalities within foraminiferid tests. Culture experiments support this hypothesis. Specimens of Ammonia beccarii (Linnk) developed abnormal chambers over a period of 12 weeks within a culture medium containing 10-20ppb of Cu.
This is the first detailed investigation of the distribution and ecology of living (stained) shallow water (0–6 m) foraminifera along the Skagerrak–Kattegat coast, eastern North Sea. A total of 25 species (13 agglutinated; 12 calcareous) are common in the 169 sediment surface samples which were collected from 27 geographic areas. The sediment grain size and total organic carbon (TOC) content are strongly variable and the salinity and temperature ranges were 10–31‰ and 9–30°C, respectively, at the time of sampling (July to October) but temperatures down to freezing occur during the winter. The species are divided into six environmental categories of which the first five comprise euryhaline and the sixth essentially stenohaline taxa: (1) species associated only with marsh plants, (2) species basically, but not entirely, associated with marsh plants, (3) species basically, but not entirely, restricted to non-marsh areas, (4) species solely recorded in non-marsh intertidal to subtidal environments, (5) species restricted to subtidal areas, (6) species basically living in the most open marine areas. In this region, marshes have a patchy distribution and they are small and compressed due to low tidal ranges (80% mud. Ammoscalaria runiana is common only in coarse-grained sediments (
Sixty-three bottom sediment samples were collected from the Burullus Lagoon with the purpose of determining the distribution pattern of the palynomorphs and microfauna, the relationship between dominant species and different environmental variables, and environmentally assessing pollution impacts following construction of a major motorway (the International Highway Project). Salinity played an important role in the distribution pattern of the living biocoenose, while temperature, dissolved oxygen and organic carbon have had a negligible effect. The biodiversity of the Burullus Lagoon is threatened by dilution of the marine water with freshwater entering the basin from irrigation canals. The high content of iron, as well as drainage water from agricultural activities, could have polluted the southern fringe of the lagoon. Heavy metal concentrations in the basin's eastern sector could also have a fatal effect on biodiversity. The opportunity is taken tomake mitigation recommendations concerning on-going environmental impacts in the lagoon.
The aim of this work has been to penetrate one of many possible avenues towards a potential ecological risk index to be used as a diagnostic tool for water pollution control purposes, i.e. to sort out which lakes/basins and substances should be given special attention. The work is based on the thesis that a sedimentological risk index for toxic substances in limnic systems should at least,account for the following four requirements.
The European Community Marine Strategy Framework Directive (MSFD) was established to provide guidelines for monitoring the quality of marine ecosystems. Monitoring the status of marine environments is traditionally based on macrofauna surveys, for which standardised methods have been established. Benthic foraminifera are also good indicators of environmental status because of their fast turnover rates, high degree of specialisation, and the preservation of dead assemblages in the fossil record. In spite of the growing interest in foraminiferal bio-monitoring during the last decades, no standardised methodology has been proposed until today. The aim of the FOraminiferal BIo-MOnitoring (FOBIMO) expert workshop, held in June 2011 at Fribourg, Switzerland, which assembled 37 scientists from 24 research groups and 13 countries, was to develop a suite of standard methods. This paper presents the main outcome of the workshop, a list of motivated recommendations with re-spect to sampling devices, sample storage, treatment, faunal analysis and documentation. Our recommendations fulfil the criteria imposed both by scientific rigour and by the practical limitations of routine studies. Hence, our aim is to standardise methodologies used in bio-monitoring only and not to limit the use of different methods in pure scientific studies. Unless otherwise stated, all recommendations concern living (stained) benthic foraminif-eral assemblages. We have chosen to propose two types of recommendations. Mandatory recommendations have to be followed if a study wants to qualify as sound and compatible to the norms. The most important of these rec-ommendations are the interval from 0 to 1 cm below the sediment surface has to be sampled, and an interface corer or box corer that keeps the sediment surface intact is to be used for offshore surveys. A grab sampler must not be deployed in soft sediments. Three replicate samples are to be taken and analysed separately. Samples are to be washed on a 63-μm screen, and the living benthic foraminiferal fauna of the >125 μm fraction is to be analysed. Splits are to be picked and counted entirely, and all counted foraminifera from at least one replicate per station have to be stored in micropalaeontological slides. Census data, supplementary laboratory data and micro-slides have to be archived. Advisory recommendations are to sample in autumn, to have a sample size of 50 cm 2 or a tube of 8 cm inner diameter, to use >70% ethanol as a preservative, rose Bengal at a concentration of 2 grams per litre for staining, and a staining time of at least 14 days. The split size should be defined by a target value of 300 specimens, heavy liquid separation should be avoided, and the 63–125 μm fraction or deeper sediment levels may be considered in some environments. We are convinced that the application of this protocol by a large number of scientists is a necessary first step to a general acceptance of benthic foraminifera as a reliable tool in bio-monitoring studies. (J. Schönfeld), ealve@geo.uio.no (E. Alve), emmanuelle.geslin@univ-angers.fr (E. Geslin), frans.jorissen@univ-angers.fr (F. Jorissen), s_korsun@ocean.ru (S. Korsun), silvia.spezzaferri@unifr.ch (S.
Most estuaries receive a high heavy-metal input from industries. This is reflected in the relatively high levels found in
numerous estuarine organisms and in sediments. Many indicators have been suggested for facilitating the detection of heavy-metal
pollution, but the problems in using these indicators to evaluate the metal loading of estuaries are considerable. Variations
in species composition, and conditions at different sites, differences in season of sampling, and age of organism, as well
as different metal levels in different parts of the organism, make the interpretation of results difficult. The levels reported
here, similar to those in other unpolluted estuaries, have been used to suggest a baseline concentration for heavy metals
in estuaries. The concept of a baseline is fundamental to the formation of a “Biological Quality Index” and “Pollution Load
Index,” and a formula for such an index is suggested and tested at a preliminary level against published data for an English
and a European estuary.
Forty two sediment samples were collected from four River Nile northern delta lakes (Mariut, Edku, Burullus and Manzalah)
to asses the man-made impact on their environment during the last 20 years. Due to the continuous discharge of agricultural,
industrial and sewage waste waters to these lakes, significant variations in the sediment's nature took place, with fine fractions
dominating opposite to the outflowing area of the main drains. Organic carbon was elevated at the southern regions, reaching
10.5 ± 4.5% in lake Mariut. Meanwhile, carbonate increased reaching 90% for samples collected at the lake-sea connection areas.
The 0.5 N HCl extractable metals indicated enriched levels of different metals at sites affected by sewage and industrial
discharge. This fraction constituted 75 and 81% of the total metals in Lakes Mariut and Manzalah, respectively. Extractable
Cd for Lakes Mariut and Manzalah constituted 51 and 53%, respectively, while Pb formed 59% of the total digestable metal in
Lake Manzalah. Total metals concentrations especially Cd and Pb were elevated 8 to 70 times than those observed in the same
lakes 25 years ago. The conversion of the untreated sewage discharge of Alexandria city to Lake Mariut and significant portion
of Cairo sewage to Lake Manzalah during the past 10 years lead to the appearance of elevated levels of contaminants in both
lakes. Agricultural discharge showed less impact on Lakes Edku and Burullus. Cluster analysis revealed associations between
stations located under same types of stress while the correspondence factor analysis displayed that metals distribution pattern
in the Nile delta lakes are governed by organic carbon as well as fine grained size fraction distribution.
To examine the suitability of benthic foraminifera and their test deformations as bioindicators of pollution in coastal marine environments, we studied foraminifera and metal concentrations in 72 marine sediment samples, collected from the inner shelf along the Sicilian coast (Gulfs of Palermo and Termini) and on the south-eastern coast of Lampedusa Island. These areas are characterised by different environmental conditions. On the basis of pollution sources and foraminiferal assemblages, we recognised different zones in the Gulf of Palermo. The most polluted zones showed high metal concentrations, and low diversity of benthic foraminifera with species typical of stressed environments. By contrast, the lowest polluted zones showed a high population density and the highest percentages of epiphytes. Epiphytes were abundant where a Posidonia oceanica meadow was present and decreased in the most polluted zones. Sediments of the Gulf of Termini and Lampedusa exhibited high percentages of benthic foraminifera typical of well-oxygenated waters and low concentrations of metals, with the exception of sites located near sewage outfalls and harbour areas. Furthermore, even though deformed tests are commonly known in natural stressed environmental conditions, this study shows that in the most polluted zones, benthic foraminifera were characterised by the highest percentages of deformed individuals.
Sources of heavy metals pollution in the Burullus Lagoon include phosphate fertilizers, sewage and oil spills from fishing boats. The benthic species identified in this lagoon are Adelosina carinata striata (Wiesner), Quinqueloculina bosciana (d'Orbigny), Quinqueloculina seminulum (Linnaeus), Ammonia tepida (Cushman), Elphidium excavatum (Terquem). A. tepida is the most dominant species in the lagoon. It constitutes more than 97% of the total benthic foraminiferal assemblages reflecting tolerance to the very low salinity in the Burullus Lagoon. The intensity of deformation was severe exhibiting a peculiar change in the coiling direction in A. tepida with increase in cadmium concentration. A. tepida exhibited a great morphological variability and the recorded morphological abnormalities show high spire giving the spiroconvex test, additional chamber, aberrant chambershape and size, twisted tests with elongated axes of rotation and complex deformities, whereas E. excavatum showed additional calcite secretion (tumors).
Assessing the extent of metal contamination in estuarine surface sediments is hampered by the high heterogeneity of sediment characteristics, the spatial variability of trace element sources, sedimentary dynamics and geochemical processes in addition to the need of accurate reference values for deciphering natural to anthropogenic contribution. Based on 285 surface sediment samples from the Loire Estuary, the first high-resolution spatial distributions are presented for grain-size, particulate organic carbon (POC) and the eight metals/metalloids identified as priority contaminants (Cd, Zn, Pb, Cu, As, Cr, Ni, Hg) plus Ag (an urban tracer). Grain-size and/or POC are major factors controlling the spatial distribution of trace element concentrations. The V-normalized trace metal concentrations divided by the V-normalized concentrations in the basin geochemical background showed the highest Enrichment Factors for Ag and Hg (EF; up to 34 and 140, respectively). These results suggest a severe contamination in the Loire Estuary for both elements. Intra-estuarine Ag and Hg anomalies were identified by comparison between respective normalized concentrations in the Loire Estuary surface sediments and those measured in the surface sediments at the outlet of the Loire River System (watershed-derived). Anthropogenic intra-estuarine Ag and Hg stocks in the uppermost centimetre of the sediment compared with rough annual fluvial flux estimates suggest that the overall strong Enrichment Factors for Ag (EFAg) and and Hg (EFHg) in the Loire Estuary sediments are mainly due to watershed-derived inputs, highlighting the need of high temporal hydro-geochemical monitoring to establish reliable incoming fluxes. Significant correlations obtained between EFCd and EFAg, EFCu and POC and EFHg and POC revealed common behavior and/or sources. Comparison of trace element concentrations with ecotoxicological indices (Sediment Quality Guidelines) provides first standardized information on the sediment quality in the Loire Estuary. The overall mean Effect Range Median quotients (m-ERM-q) results suggested that the Loire Estuary is mainly characterized by slightly toxic sediments even if ecotoxicological impacts have been previously reported on biota.
Some of the relatively recent literature correlating morphological variation in benthic foraminifera with environmental parameters is reviewed. It appears some variables (most notably depth) are recorded more frequently, which may affect some conclusions. Although each variable is treated separately, it appears that almost no variables act independently on test morphologies. In reviewing the literature, it bcomes clear that there are many individual trends, especially with shell ornamentation, but few broad ones, and that it is almost impossible, with exception of some of the larger reef-dwelling, symbiont-bearing foraminifera, to predict how any species will react to various parameters. The broad trends concern thinning or thickening of carbonate tests with changing carbonate availability, temperature, and salinity. It appears that many observations of morphological changes within species may not be recorded in the literature. -from Authors
In this study, living (Rose Bengal stained) foraminiferal faunas from 31 stations along the entire French Mediterranean Sea coast except Corsica have been analysed. In the context of the Water Framework Directive, the aim was to develop a biotic index to evaluate the benthic ecosystem quality. Therefore, different faunal parameters (diversity indices, wall structure proportion, and indicative species groups) have been tested to determine their relevance as indicators of environmental conditions. The best results are obtained with a biotic index based on the relative proportion of stress-tolerant taxa. For ecosystem quality evaluation, it is essential to distinguish between natural and anthropogenic eutrophication phenomena. In order to do so, we applied a correction on our biotic index, using the expected percentage of stress-tolerant species in natural environments, in function of sediment grain size (percentage <63 mu m). Finally, a comparison of the different faunal parameters calculated for two different sediment intervals (0-1 and 0-4 cm) indicates clearly that the analysis of the uppermost centimetre of the sediment is sufficient to obtain relevant information needed for bio-monitoring purposes.
Coastal benthic foraminifera are widely studied as indicators of environmental disturbance. This paper presents a synthesis of the studies that showed correlations between foraminiferal assemblages and various environmental problems along the western French coasts. Pollution in coastal environments may be chronic, resulting from current activities, or may result from accidental events. All the studies show that foraminifera may be used as indicators of pollution after deconvoluting from natural impacts. The most sensitive foraminifera identified by these studies are Haynesina germanica, Ammonia tepida, Cribroelphidium excavatum, bolivinids and Eggerelloides scabrus.
A study of foraminiferal assemblages was carried out at two Egyptian Nile Delta lagoons. Analysis of surficial sediment samples from Manzalah Lagoon shows enrichment in heavy metals (Pb, Zn, Cu, Cr and Cd). The environment has become so lethal to foraminifera that no species can currently survive. Among ostracods, only one species (Cyprideis torosa) was found living and able to invade the polluted lagoon region. Samples from Edku Lagoon, which receives only agricultural drainage water, show heavy metal concentrations close to natural baseline levels, and yield living foraminifera, The frequent occurrence of deformed specimens in Manzalah Lagoon, comparable to Edku Lagoon, reveals that: (1) benthic foraminifera are more sensitive to industrial wastes containing heavy metals; (2) agricultural wastes do not significantly harm benthic foraminifera; (3) Ammonia beccarii forma parkinsoniana is less resistant to pollution than forma tepida; (4) morphological abnormalities of the foraminiferal tests depend upon the nature of the pollutant; and (5) benthic foraminifera are less tolerant to pollution than ostracods and molluscs.
The paleoecological interpretation of fossil foraminiferal assemblages depends on an understanding of the ecological processes operating at the present. This study investigates both the quality of organic matter (OM) by elemental analysis as well as the sediment grain size and clay mineralogy to understand their relative influence on distribution and abundance of benthic foraminifera. This study is carried out on 15 samples regularly spaced from the mudflat to the tidal marsh. The results indicate that grain size is the most limiting parameter. Living (stained) benthic foraminiferal density and species richness are both very low within coarser sediments. OM is the second limiting factor. The density of foraminifera is the lowest and the species richness is the highest with the lowest organic carbon (Corg) contents and C/N12, the density is high and the species richness medium. A high smectite proportion within the clay-size fraction seems to favor the development of Miliammina fusca. Trochammina inflata and Jadammina macrescens are both favored by an increase of organic carbon proportion but Trochammina inflata preferentially feeds on algal-derived OM when compared with Jadammina macrescens.
This paper presents a table of abundances of the elements in the various major units of the Earth's lithic crust with a documentation of the sources and a discussion of the choice of units and data.
Sediments are considered the sink for metals in aquatic environments because of their strong metal-binding capacity, but they are a potential source for metal ingestion by marine benthic animals as well. Sediment contamination is now a major environmental problem in many countries, including China. This study examines the bioavailability to a marine suspension-feeder (the clam Mactra veneriformis) and a deposit-feeder (the peanut worm Sipunculus nudus) of sediment-bound Cd, Cr and Zn along a gradient of metal contamination. To this end, metal assimilation efficiency and metal extraction by gut juice were quantified and compared. Metal concentrations in sediments collected from 4 sites were 5.40 to 43.7 mgCd kg(-1), 32.8 to 71.2 mgCr kg(-1), and 278 to 5 380 mgZn kg(-1). Metal assimilation by the clams was independent of the metal concentration in the sediment. In the deposit-feeding sipunculid, the bioavailability of sediment-bound Cd increased with increasing contamination of the sediment, as a result of the increasing partitioning of Cd into the easily exchangeable phase, and decreasing partitioning into the reducible phase. Cd assimilation also increased with increasing total organic carbon content in the sediments. The Cd assimilation efficiency was directly correlated to Cd extraction by gut juices collected in vitro from the peanut worm. No such relationship was found for Cr and Zn. Geochemical and biological controls on metal bioavailability therefore differ between the metals and with the extent of sediment contamination. The limitation of the radio-tracer technique to quantify metal assimilation efficiency by marine benthic invertebrates from sediments should be recognized when it is used to predict metal concentrations in target animals.
Cited By (since 1996): 39, Export Date: 4 December 2012, Source: Scopus
We investigated morphological abnormalities of Recent benthic foraminiferal tests in paralic environments of Brazil from two estuaries (Rio Guaraú and Rio Una located in the tropical forest) which are not affected by human activities in comparison to one polluted estuary (Baixada Santista), and one hypersaline lagoon (Araruama). The highest percentage of abnormal tests occurred in Rio Una (29%) and was caused by decalcification/recalcification processes resulting from natural periodical acidification. In the Rio Guaraú, percentages of abnormal tests reached 10%. The strong hydrodynamics in this estuary induced damage in living foraminiferal tests and the shape of the tests resulting from the regeneration of a damaged chamber, was often abnormal. In the lagoon of Araruama, percentages of abnormal tests reached 24%. Here, hypersalinity and strong salinity variations seem to perturb the test construction of foraminifers. In the most polluted estuary (Baixada Santista), lower percentages of abnormal tests occurred (0–7% with only one station reaching 12%). In this paralic environment, it is difficult to distinguish between the effect of natural stress and anthropogenic impact. Our study shows that higher percentages of abnormal tests occur in non-polluted areas than in polluted areas. Thus, the relative abundance of abnormal tests used as a bio-indicator of pollution in paralic environments, which are subject to strong natural stress, must be handled with care. Nevertheless, the relative abundance of abnormal tests is a useful proxy for the reconstruction of paleoecological changes in stressed paleoenvironments.
A detailed comparative study of Recent benthic foraminiferal populations was conducted at two bays (El-Mex and Miami) located along the Mediterranean coast of Alexandria, Egypt. Nine samples from each bay were studied and a total of 78 benthic foraminiferal species belonging to 19 families were identified. Porcellaneous forms were dominant, comprising 65% and 68% of the total population in El-Mex and Miami bays, respectively. El-Mex is one of the most metal-polluted areas along the Alexandrian coast. It is contaminated by industrial wastes, chiefly heavy metals, as well as agricultural and domestic effluents. Increasing pollution results in low species diversity and population density, associated with an increase in tolerant or opportunistic species. The extent to which population was found to be impoverished corresponded to the degree to which the sediment was contaminated. In this contaminated environment, foraminiferal tests were stunted and aberrant tests were frequently found. Species diversity and population density were higher in Miami Bay (domestic sewage) and deformed forms were scarce. X-ray microanalysis reveals that living deformed specimens contain higher levels of heavy metals (Pb, Zn, Cu, Cr, and Cd) than non-deformed ones. This strongly suggests that heavy metals are responsible for the abnormalities in foraminiferal tests. The study illustrates that the mode of test deformation depends upon the degree of pollution and type of pollutants. Benthic foraminifera reflect human-induced environmental perturbation and they can be used as bioindicators for monitoring coastal pollution.
Port Joinville harbor is located on an island. Thus, it receives only a few freshwater inputs, contrary to most of the areas where the influence of pollution on foraminiferal assemblages has been studied. The pollution in the harbor mainly results from the boats, including cleaning, painting and outfall of oil and motor-fuel.A total of 59 sediment samples was collected at three sampling periods (November–December 1997, May 1998 and September 1998). These samplings were supplemented by the study of algal flora and macrobenthos and by the study of water circulation by means of six stations where water was collected every hour during a tide cycle. Contaminants were analyzed in the last series of 17 samples. Total assemblages were used for this study. This choice is explained and discussed.This study shows that the main factor that determines the distribution of foraminiferal species in Port Joinville harbor is the geographical position. The correlation that occurs between heavy metals and the silt and clay fraction makes it difficult to determine whether sediment characteristics or pollution have the stronger influence on foraminiferal assemblages, except in areas heavily affected by pollution. Polluted sediments, near the careening areas, are indicated by the tolerant pioneer species Cribroelphidium excavatum and Haynesina germanica. The growth of epiphytic species depends on the presence of algae and their distribution may be favored by local conditions such as the constant immersion of the supports in the wet dock.
This paper examines the spatial and temporal distribution of heavy metals (Fe, Al, Cu, Zn, Mn, Cd, Pb and Ni) from three short sediment cores collected from Burullus lagoon of the Nile delta, Egypt. 210Pb and 137Cs measurement is applied to understand sedimentation rate and related chronology. Remarkably low isotopic activities and intensive bioturbation in the lagoonal sediments rendered age determination difficult. Samples with detectable 137Cs in the upper core sediments together with sediment lithology could help infer a sedimentation rate of about 2.0 mm yr−1, thereby indicating post-dam (after 1964) sedimentation of the upper 10-cm core sediments. Our results demonstrate that most heavy metals in the surficial sediments after normalization to Al decrease seaward, showing a function of distance to the sewerage outlet on the inland lake coast. Also, there is an upwardly increasing trend of normalized heavy metals, especially in the upper 10-cm core sediments. Relevancy analysis has identified Mn, Pb and Cd as the diagnostic heavy metals in Burullus lagoon, most likely derived from Tanta and Kafrelsheihk, the major downtowns in the central Nile delta plain, from where wastewaters are directly discharging into the lake via canal networks. Although Burullus lagoon is presently least affected by pollution as compared to other major lagoons of the Nile delta, the increasing quantities of diagnostic metals, especially Mn, are extremely toxic, as they are potentially linked to the risks of digestive issues and pancreatic cancer reportedly. The situation calls for a rational planning for sewerage treatment in the protected Burullus coast.
A study to determine total and mobile heavy metals concentrations in sediments from Algeciras Bay was performed and pollution hotspots were identified. The effects on aquatic organisms were established using sediment quality guidelines (SQGs). Ni and Cr exceeded the effect range medium and low levels, respectively, around industrial area. Potential toxicity of metals was determined by diethylenetriaminepenta-acetic acid (DTPA) extractions and low alert levels of Co, Cu, Zn, Cd, Ni and Pb were exceeded at most sampling sites. Three pollution indicators were used showing significant values for As, Ni, Cr, Pb and Cd. Sediment speciation using the sequential extraction BCR procedure was carried out, being Cd, Zn, Pb and As the most available metals. Principal component, cluster and ANOVA analyses were performed in order to assess the sources of metals and the influence of seasonality and anthropogenic activities on the sediment quality. Two principal component analysis (PCA) factors were obtained identifying the sampling sites affected by anthropogenic activities; Ni-Cr and Zn-Cu-V clusters were also obtained associated with stainless steel and petrochemical industrial activities. ANOVA showed the outstanding sites because of total metal concentration and significant differences among sampling sites by the acid extractable and reducible fractions for all metals except for Ba and V.
Living benthic foraminiferal assemblages were studied in surface samples collected from the lagoon of Venice (Italy) in order to investigate the relationship between these sensitive microorganisms and trace element pollution. Geochemical analysis of sediments shows that the lagoon is affected by trace element pollution (Cd, Cu, Ni, Pb, Zn and Hg) with the highest concentrations in its inner part, which corresponds to the Porto Marghera industrial area. The biocenosis are largely dominated by Ammonia tepida, Haynesina germanica and Cribroelphidium oceanensis and, subordinately, by Aubignyna perlucida, Ammonia parkinsoniana and Bolivina striatula. Biotic and abiotic factors were statistically analyzed with multivariate technique of cluster analysis and principal component analysis. The statistical analysis reveals a strong relationship between trace elements (in particular Mn, Pb and Hg) and the occurrence of abnormalities in foraminiferal tests. Remarkably, greater proportions of abnormal specimens are usually found at stations located close to the heaviest polluted industrial zone of Porto Marghera. This paper shows that benthic foraminifera can be used as useful and relatively speedy and inexpensive bio-indicators in monitoring the health quality of the lagoon of Venice. It also provides a basis for future investigations aimed at unraveling the benthic foraminiferal response to human-induced pollution in marine and transitional marine environments.
The main goal of this study is to determine the present heavy metal pollution state in the two gulfs of the Aegean Sea; Saros and Gökova Gulfs. The surface sediments were collected from 11 and eight locations in the Saros and Gökova during May 2001, respectively. The results showed that the sediments of Saros and Gökova gulfs were polluted with Pb, Cr, Zn, Mn, and Ni and Pb, Cr, Ni, and Mn, respectively. For various metals the contamination factor (CF) has been calculated to assess the degree of pollution in sediments. The sediments were noted to be not contaminated with Hg, Cd, and Cu in all areas. Moderate contaminations were observed for Pb, Cr, and Zn in Saros Gulf. The CF was moderate and very high for Ni in the Saros and the Gökova Gulf, respectively.