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Heavy Metals in Sediment Cores of Gao-ping Canyon Nearby AreasChen, Hung-Lin 08 September 2010 (has links)
The main purpose of this research was to analyze the distribution and accumulation of metals in sediment cores of Gao-ping Canyon nearby areas. Enrichment factor (EF) and Sediment Quality Guidelines (SQGs) were also used to assess the pollution history, sources and extent of heavy metal pollution.
The results revealed that copper and cadmium metal concentrations have not been contaminated significantly; while zinc and lead concentrations reached moderate degree of pollution, which exceeded guidelines of Low-SLG in Ontario and ERL in NOAA. The concentration of lead was higher than most found in Taiwan. Although chromium was found mild polluted, but attention should still be paid as those concentrations exceeded the values of Low-SLG¡BSevere-SLG and ERL.
Comparing results from cores in Southern and Northern shelves of Gao-ping Canyon, the trend of heavy metal concentrations in Northern shelf rose gradually but had an apparent downward trend in surface mixed layer; while distinct variation with time was observed in Southern shelf.
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The relationship between hydrological and nutrient conditions in the Dongsha AtollShen, Yi-jie 02 November 2012 (has links)
This study focuses on the relationship between hydrological and nutrient conditions in seawater surrounded by Dongsha Atoll. Dongsha Atoll is located in the northern South China Sea (NSCS), the water properties should be in coherence with the NSCS water masses. However, due to the semi-enclosed topography the water inside Dongsha Atoll is largely affected by local insolation and rainfall.
Significant relationships between SiO2 or PO43- and salinity indicate that rainfall could be a major source of these nutrients. Insignificant relationship between N+N and salinity indicates that rainfall and nitrogen fixation both might affect the distribution of N+N. Temporal variations of temperature and chlorophyll a were alike, except for which occurred in July, 2011. It was probably caused by photo inhibition on phytoplankton growth. The inventory of chlorophyll a was positively correlated with both N+N and SiO2 but not with of PO43-, indicating that phytoplankton growth in Dongsha Atoll was mainly affected by N+N and SiO2. Phytoplankton growth maybe limited by N+N but not by SiO2, as the concentration of SiO2 was mostly beyond the limitation concentration for phytoplankton. According to close relationships between chlorophyll a and TSM, POC and PN, the particulate matter maybe mainly derived from biological origins. The inventory of chlorophyll a was positively correlated with both dissolved organic carbon (DOC) and dissolved organic nitrogen (DON), manifesting the importance of biological origins for DOC and DON concentration.
The ratios of DOC/DON, DON/DOP and DOC/DOP within the atoll were in ranges of 7.34-303 (mean: 30.4), 3.00-142 (mean: 22.7) and 104-2546 (mean: 421), respectively. The ratios are higher than those values in NSCS and East China Sea, implying the excretion of carbon-enriched DOM by phytoplankton. The concentration of chlorophyll a, DOC and POC were higher in the Small Lagoon than in the Atoll Lagoon, implying a relatively high productivity in the Small Lagoon.
The fluxes of carbonate in the atoll was more than 30 times of the flux in the NSCS, due to its unique characteristics in the coral reef habitat. The organic matter of settling particulates was mainly derived from biological sources. The metal of enrichment factor of settling particulates reveals that Fe and Al are mainly derived from crustal sources, while Cu, Zn and Pb are likely influenced by anthropogenic sources.
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Investigation of pollution coming from copper, lead, and zinc mining, and factors controlling mobility and bioavailability of pollutants at Ecton Hill, Staffordshire, UKAl-Ibrahim, Zahid Omar Mustafa January 2017 (has links)
Former mining areas are well-known globally to be a significant anthropogenic source of contaminants being dispersed into the surrounding environment. Various human activities, including ore mineral mining, industrial activities, domestic waste production, and the agricultural application of fertilisers and pesticides, are likely to contribute to the release of huge amounts of potentially toxic metals into the ecosystem, which have harmful effects on the flora and fauna and on human health. Therefore, the main aim of this study is to evaluate the contamination that arises from some selected heavy metals (Cu, Pb, Zn, Mn, Cr, Ni, and V) in topsoil and floodplain samples from the Ecton mining area. Ecton Hill is located in the southern part of the Peak District, Staffordshire, England, and bounded by the River Manifold from the west. This area has been mined for sulphide minerals, which were extracted extensively from the 16th century until the mid-19th century; the area is currently being used for cattle rearing and agricultural purposes. Therefore, it would be worth finding out the extent to which the area has been polluted by the aforementioned metals. To this end, topsoil and floodplain samples were collected and analysed for their total concentrations using XRF technique and different granulometric classes (i.e. clay, silt, and sand) using a (Malvern Mastersizer Long Bed) laser granulometer with a presentation unit of MS-17. In addition, soil specific factors, including organic matter content, organic carbon, pH, Eh, and cation exchange capacity were also measured. Spatial distribution maps were constructed using a GIS approach for the metals studied over the study area. Contamination and ecological risk assessments were carried out via the geoaccumulation index (Igeo) and enrichment factors (EF) respectively. Moreover, collected soils for different land uses have been assessed using the UK government soil guidelines (i.e. ICRCL and CLEA's SGVs soil values). Furthermore, the bioavailability, leachability, and fractionation (using five-steps sequential extraction) of the metals in various soil phases were characterised using correlation matrix and principal component analysis (PCA) approaches. The GIS- based spatial analysis maps reveal that elevated concentrations of the metals are located around the sites of the mining waste in the area. The contamination assessment results indicate that Cu, Pb, Zn have a contamination degree ranging between strongly contaminated (class 4) and extremely contaminated (class 6). The results of the ecological assessment by enrichment factor (EF) show that Pb has the highest enrichment factor. The bioavailability results of the heavy metals under study, via EDTA, show that Cu, Pb, Zn have the highest bioavailable fractions. The regression analysis demonstrates that Mn gives the best fit regression equation with the highest R2 value of 0.825. The leachability results reveal that, of the seven heavy metals, Zn has the highest leachable value, whereas the lowest leachable was recorded for Cr. Speciation was measured using the five-steps procedure, and the results show that Cu, Pb and Zn are mainly associated with the organic matter fraction, whilst, Cr, Ni and V are associated with the residual fraction. The principal component analysis (PCA) revealed that oxides of Fe/Al, organic matter, and the clay and silt fractions are the main soil parameters responsible for binding heavy metals to the soil surfaces of the study area. Changing the redox potential conditions and acidification was investigated and the results indicate that such changes have significant effects on the release of heavy metals from the soil particles at Ecton Hill.
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Development of river water quality and sediment management strategiesLin, Chih-En 24 August 2010 (has links)
The river water quality management strategy involves a series of complex inter-disciplinary decisions based on speculated responses of water and sediment quality to changing controls. In the aquatic system a rapid removal of the heavy metals from the water to sediments may occur by settling particles while some of these pollutants can be mobilized by getting accumulated into the biota from the sediments sink. Thus, sediment plays a major role in the determining pollution pattern of aquatic systems. It acts as both carriers and sinks for contaminants, reflecting the history of pollution, and providing a record of catchment inputs into aquatic ecosystems.
The Yan Shuei Gang River watershed is one the river watersheds in Kaohsiung City, Taiwan. It is 5-km long, drains a catchment of more than 1,200 ha. Part of the river water is from the domestic drainage areas located in the upper catchment. In Linhai Industrial Parks, there are more than 493 registered industrial factories that discharge their wastewater into the Yan Shuei Gang River. Thus, recent water and sediments quality analysis indicates that the Yan Shuei Gang River is heavily polluted.
The major objectives of this study were to (1) perform water quality and sediments sampling and analyses, (2) perform water quality simulation and demonstrates the model application to the Yan Shuei Gang River, (3) assess the water and sediments quality, (4) provide foci for immediate remediation efforts, (5) provide benchmark levels to test outcomes of future remediation efforts, (6) design a novel extraction technique that utilizes a mildly elevated pressure in consecutive cycles with a chelating agent for the sediment slurry.
Water quality investigation results show that the biochemical oxygen demand (BOD), ammonia-nitrogen (NH3-N), and suspended solid (SS) average concentrations in water samples of the Salt-water River varied from 10.2 to 194, 8.51 to 18.3, and 7.9 to 19.5 mg/L, respectively. The results of the chemical analysis of the Salt-water River surface sediments showed that the sediments present highly elevated Cd, Cr, Ni, Cu, Pb, Zn and Fe concentrations. Investigation results reveal that sediment samples contained significant amount of iron (up to 3.6%), Cr (up to 66.5 mg/kg), Pb (up to 36.5 mg/kg), Ni (up to 43 mg/kg), and Al (up to 1.8%). All heavy metal concentrations were higher than the world average, sediments average and sediment quality guidelines (SQGs). Although all metals showed varied concentrations, the approaches of factor analysis, normalized enrichment factor (EF), and the geo-accumulation index (Igeo) proposed in this paper were effectively used to differentiate the natural and anthropogenic sources of the metals.
Both the EF and Igeo indicated similar anthropogenic contamination degree of the metals. The potential acute toxicity in sediment of Yan Shuei Gang River was observed to be mainly due to Cu contamination. Cu was the major toxicity contributor accounting for 32-46% of the total toxicity in Salt-water River, followed by Zn.
The Water Quality Analysis Simulation Program (WASP) model developed by US Environmental Protection Agency (EPA) was selected as a water quality planning tool to perform the water quality evaluation. Modeling results show that the current daily pollutant inputs were much higher than the calculated carrying capacity for nutrients and BOD of the Yan Shuei Gang River. Based on the results from this study, the following remedial strategies have been proposed to minimize the impacts of industry and domestic source pollution on the water quality of Salt-water River: (1) increase the flow by transporting 1 m3/s unpolluted surface water from other sources to dilute the polluted river water, (2) construction of the intercepting systems to effective intercept and transport the untreated wastewater to the wastewater treatment systems.
The sediments batch extracted by 150 psi pressure cycles has the most Cu removed rater (70%), much higher than without treatment (55%) or with 90 psi pressure cycles treatment (65%). Pressure-assisted extraction achieves in 60 min the amounts of Cu equal to or exceeding those achieved in 240 min without pressure cycles under the same concentration conditions. This research indicates that the advantages of pressure cycle system are increased process speed, more thorough extraction, and reduced use of the chelating agent. The heightened treatment is explained by sediments aggregate fracturing upon pressure cycles that exposes the contaminants as well as by the chelating agents. The technique is expected to accelerate extraction treatment of a wide range of heavy metal contaminants, and it may provide treatment to dredged and stored contaminated sediments.
Experience obtained from this study will be helpful in designing the sediment and river management strategies for other similar river watersheds.
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Heavy Metals in Sediment of Gao-ping Submarine CanyonChen, Ming-hung 15 February 2011 (has links)
This research investigated the accumulation of metals (Cu, Zn, Cr, Pb, Cd and Fe) in sediment of Gao-ping River and Gao-ping submarine canyon. Both Sediment Quality Guidelines (SQGs) by National Oceanic and Atmospheric Administration (NOAA) and Soil Quality Guidelines by Taiwan Environmental Protection Agency (EPA) were used to assess the extent of risk of these metals to the local ecological system.
The results found no significant correlation between concentration of metals and volatile solid as well as particle size. It is noted that significant contaminations in zinc and lead were observed in sediments from both Gao-ping River and the starting point of Gao-ping submarine canyon, which concentrations exceeded the guidelines of Effect Range-Medium (ERM) by NOAA. Very likely, this is resulted from the metal and electroplating factories in the catchment area of Gao-ping River. It also provides evidence of the role of Gao-ping submarine canyon in accumulation of terrestrial and anthropogenic pollutants.
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The seasonal trend and characteristics of heavy metals in atmospheric particulates in Nantzu Export Processing ZoneChang, Hung-Tse 15 August 2012 (has links)
To characterize the size distributions, concentrations and sources of heavy metal associated with suspended particles, a total of 12 months of sampling periods were taken by Micro-Orifice Uniform Deposit Impactor (MOUDI) in the Nantzu Export Processing Zone from January to December 2011,
The concentrations of suspended particles ranged from 54.7 to 203 £gg/m3. Both autumn and winter had significantly higher levels of suspended particles than in spring and summer. The mass concentrations of fine particles accounted for ~50% of the mass concentrations of suspended particles. The mass concentrations of PM2.5 accounted for 50.2-70% of the mass concentrations of PM10. The mass concentrations of PM1 accounted for 24-38.3% of the mass concentrations of PM10. These results indicated that fine particles dominated in atmospheric particulates in Nanzih Export Processing Zone. In addition, among the PM10, PM2.5 and PM1, significant correlations were found.
The crustal elements (Al, Fe, Ca, Mg, K and Na) and sulfate are dominant during the sampling periods, which accounting for ~95% of the total concentrations. The crustal elements were observed mainly in coarse particles, while sulfate was found mainly in fine particles. The concentrations of all crustal elements decreased in summer could be attributed to the meteorological conditions and chemical mechanism. By using the enrichment factor (EF) to distinguish the sources of heavy metals in PM10, PM2.5 and the results showed that EF values of crustal elements in PM10 ranged from 1 to 10, suggesting PM10 might come from the resuspension of soil and road dust. In addition, Pb, Zn, As, Se, Mo, Sb and sulfate were observed at higher EF values in both PM2.5 and PM1, indicating the influence of anthropogenic emissions in fine particles.
The results from Pearson¡¦s correlations indicated that PM10 in the Nantzu Processing Zone were mainly from the resuspension of soil and road dust, while fine particles (PM2.5 and PM1) may be from the traffic emissions and petrochemical industry in Nanzih and Renwu.
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Distribution of Heavy Metals and Simulation of Ocean Disposal of Harbor SedimentsChen, Chiu-Wen 18 November 2006 (has links)
The distribution, enrichment, and accumulation of heavy metals in the sediments, especially those at the vicinity of tributary estuaries of Kaohsiung Harbor, Taiwan were investigated. Sediment samples from six locations in the Kaohsiung Harbor were collected quarterly in the period from 2002 to 2005 and characterized for metal content (e.g., Hg, Pb, Cd, Cr, Cu, Zn and Al), water content, organic matter, total nitrogen, total phosphorous, total grease, and grain size. Results showed that metal concentrations varied from 0.58 mg kg-1 for Cd to 596 mg kg-1 for Zn. Metal concentrations at the vicinity of river mouths were higher than those at other locations. All heavy metals studied, except Cr, had relatively high enrichment factors and geo-accumulation indices in the estuaries. Moreover, metal concentrations correlated closely to the physical-chemical properties of the sediments, which strongly suggested the influence of industrial and municipal wastewaters discharged from the neighboring industrial parks and river basins. Results would help develop strategies for pollution control and sediment remediation of Kaohsiung Harbor.
Ocean disposal of wastes such as dredged sediments causes the concentrations of contaminants and some other water quality parameters in the water column to change. In this study, the STFATE (Short-term Fate) system, a model developed by the US Corps of Engineers for managing automatic dredging and disposal of the dredged materials, was used to model and simulate the deposition, dispersion and accumulation of the dredged material disposed at an ocean site. Additionally, aerial photographs taken from a helicopter on dispersion of the disposed sediments were used to calibrate and verify the modeling results for evaluating its applicability in predicting the influence of disposing dredged sediments on the surrounding seawater quality. Simulation results indicate that after 4 h of ocean disposal, the dredged sediment showed negligible adverse influence on the seawater quality (SS = 3 ¡V 4 mg/L). Results of simulating the dispersion of dredged sediments revealed that 20 seconds disposal duration resulted in smaller influence distance and range but a longer time for the seawater to recover to its original state. A longer disposal time of 1,200 seconds would cause a larger distance and range of influence but a shorter recovery time. The verification results demonstrate that simulated values on the dispersion length, width, area and shape generally comfort to the trends of monitored data; the average error is around 27.8%.
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Physicochemical Characteristics and Source Allocation of Asian Dusts Sampled in Penghu IslandsLiu, Yi-chi 25 August 2008 (has links)
In recent years, the Asian dust storms occurred frequently. It was estimated that approximately eight hundred million metric tons of Asian dusts transported to the atmosphere yearly. During the dust storm period, Asian dusts not only induce poor air quality, but also reduce atmospheric visibility and influence human health.
In order to investigate the physicochemical characteristics and source allocation of Asian dusts, this study collect the Asian dusts in the Pescadores Islands during the years of 2002~2006. In addition, this study collected top soils in three regions of Inner Mongolia and resuspended the soil samples in a resuspension chamber to analyze their chemical composition. Moreover, this study applied enrichment factor analysis (EF) and grey relational analysis to allocate the potential sources of Asian dusts and compare them with the transportation routes obtained from backward trajectory.
During Asian dust storm periods, the concentration of atmospheric particulate matter (PM10) in the Pescadores Islands increased significantly, probably is 3~6 times of PM10 during non-dust storm periods. Among them, coarse particles (PM2.5-10) particularly rose from 10~30 £gg/m3 to 80~130 £gg/m3 and the size distribution changed from bi-modal distribution to single modal distribution of coarse particles during Asian dust storm periods.
This study further analyzed the chemical composition of Asian dusts, including water-soluble ionic species, carbon contents, and metallic contents. For fine particles (PM2.5), the order of water-soluble ionic species was SO42- > NH4+ > NO3- > Cl- > Ca2+ > Na+ > K+ > Mg2+ > F-. For coarse particles (PM2.5-10), the order of water-soluble ionic species was Cl- > SO42- > NO3- > Na+ > Ca2+ > NH4+ > Mg2+ > K+ > F-. The carbon contents distributes mainly in fine particles. The major contents of both fine and coarse particles were crustal elements (i.e. Al, Fe, Na, Mg, K, Ca, and Sr).
In addition to the analysis of physicochemical characteristics of Asian dusts, this study applied HYSPLIT MODEL to figure out their transportation routes by backward trajectory. According to the backward trajectories, this study compartmentalized Asian dusts storm transportation routes into three categories: Eastward Transportation and Retraced (ETR), Southeasterly Transportation and Circumrotated (STC), and Straight Southeasterly Transportation (SST). Analyzing the spatial and temporary background variables to investigate the influence of transportation routes on Asian dusts¡¦ physicochemical characteristic. This study revealed that the physicochemical characteristics were very similar for same category of Asian dust storms, which can be used to allocate the source regions of Asian dust storms.
This study resuspended the soil samples collected in Inner Mongolia inside a resuspension chamber and collected the suspended particles (PM2.5, PM2.5-10) for chemical analysis. Chemical analysis results indicated that the fingerprints of chemical composition for different regions were similar but still distinguishable, which can be used to identify the source areas of Asian dusts. This study further compare and correlate the Asian dusts collected at the Pescadores Islands during Asian dust storm periods with the soils collected in Inner Mongolia chemically by enrichment factor and grey relational analysis.
This study further compared the source allocation of Asian dust storms obtained from enrichment factor, grey relational analysis, and backward trajectory and found the results of these three methods were quite similar. For enrichment factor analysis, 88% of similarity was obtained by using two separate reference elements (Al and Fe). The similarity of backward trajectory and grey relational analysis reached as high as 83%. Moreover, the backward trajectory and enrichment factor were similar up to 75%, while the grey relational analysis and enrichment factor were similar up to 69%.
Overall, two out of three aforementioned methods can effectively allocate the source regions of Asian dusts by 94%, while all three methods can successfully allocate the source regions of Asian dusts by 56%. Comparison of three aforementioned methods showed that they can be applied to allocate the source regions of Asian dusts.
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Physicochemical Characteristics and Tempospatial Variation of Suspended Particles at Inland and Offshore Sites in KaohsiungTi, Tsung-hung 27 August 2008 (has links)
Kaohsiung region with high percentage (6-8%) of poor air quality (PSI>100) has been announced officially by Taiwan Environmental Protection Administration (TEPA) as the worst air quality region among seven Air Quality Zones (AQZ) in Taiwan. Air pollutant dispersion was influenced by many factors including meteorology and topography. Particulate matter (PM) transportation caused by northeastern monsoon and/or sea land breeze might resulted in air pollution episodes. In summer, PM might be transported back and forth across the coastline of Kaohsiung region by sea land breeze. Particularly, high PM10 concentration has been observed at the inland sites in the daytime due to sea breeze. In autumn and winter, PM could be transported northeasterly to the inland range and covered a huge area of entire region. The objective of this study was to investigate the accumulation of particulate matter in the near-ocean region due to northeastern monsoon and sea-land breeze, and the spatial and temporal distribution of PM in the coastal region of Southern Taiwan.
This study investigated the effects of sea-land breeze and northeastern monsoon on the spatial distribution and temporal variation of particulate matter in the atmosphere around the coastal region of South Taiwan. Particulate matter was simultaneously sampled both inland and offshore during five intensive sampling periods on August 16-17, 2006, November 2-3, 2006, January 24-25, 2007, March 6-7, 2007 and May 2-3, 2007, respectively. Inland monitoring was conducted at two sampling sites associated with fourteen Taiwan ambient air quality monitoring stations, while offshore monitoring was conducted at the Hsiau-Liou-Chiou (HLC) island (approximately 14 km offshore) and on an air quality monitoring boat. In August and November, 2006 and May 2007, sea-land breeze was observed during sampling period and sea breeze arose from 9:00 A.M. to 24:00 P.M. The average wind velocity was 1~4 m/sec during the sampling period. In January and March, 2007, prevail wind direction was north and northeast (300 o ~30 o), that was influenced by northeastern monsoon. The average wind velocity was 2~4 m/sec during the sampling period.
The backward trajectories of air parcel transported toward the inland ambient air quality sampling sites around the coastal region of South Taiwan were plotted during the sea land breeze and northeastern monsoon periods. The results showed that distribution of PM10 was significantly influenced by sea land breezes. During the sea-land breeze periods, sea breezes blown in the early morning would transport the offshore PM10 back to the inland sites in Kaohsiung metropolitan area resulting in high PM10 concentration in the afternoon. On the contrary, high PM10 concentration observed during the northeastern monsoon periods was mainly brought from northerly wind which transported PM10 originated from the northern region (i.e. Tainan and Yunlin Counties) to Kaohsiung metropolitan area.
This study further compared the atmospheric aerosols sampled at Kaohsiung metropolitan area with the resuspended sands blown from top soils collected near the riversides. An enrichment factor (EF) was applied to correlate the downwind atmospheric aerosols at three TEPA sampling sites in Kaohsiung to top soil sources originated from Tachia river, Zhoushui river, Tesngwen river and Kaoping river, respectively. This study revealed that atmospheric aerosols sampled at Southern Taiwan can be correlated to top soil sources near the riversides. Further investigation of enrichment factors indicated that, among four rivers, Kaoping river had the highest correlation to PM10 sampled in Kaohsiung. The enrichment factors were in the order of Kaoping river (EF=0.8~1.9) > Tsengwen river (EF=0.8~2.6) > Zhuos river (EF=1.0~2.8) > Tachia river (EF=1.1~4.2). The results indicated that atmospheric aerosols (i.e. PM10) had relatively higher correlation with the nearest river, Kaoping river, than other three rivers.
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Undersökning av miljöpåverkan från järnsand i en sedimentstudie i Inre-viken, Skellefteå / Using sedimentary records to investigate iron sand’s environmental impact in Inre-viken, Skellefteå (English)Rikard, Haldebo January 2015 (has links)
With rapidly urbanizing societies, waste management needs attention. In 2008, EUs Waste Framework Directive (WFD) set new concepts, like reducing usage of natural materials. Thus, the interest for alternative materials increased. In Skellefteå, since the 1970’s, iron sand has often substituted natural gravel in road construction. But, today stricter regulations might forbid iron sand for further use. The issue is whether leachate from iron sand causes heavy metal pollution or not. This thesis tried to provide more knowledge into iron sand’s environmental impact. In order to investigate this, a sediment sample (<53 cm deep) collected in Inre-viken, a lake 50m from a road with iron sand, were analyzed for Zn, Pb and Cu concentrations. Enrichment factor (EF), national benchmarks, and reference data were used to evaluate anthropogenic impact and age-determine the sediment. The results showed: (1) Inre-viken has elevated heavy metal levels compared to pre-industrial levels, with highest Cu (133 mg/kg) and Zn(204 mg/kg) concentrations found in the surface layer. (2) Zn and Cu showed an increase between 41-0 cm depth (1970-2015), but only Cu reaches high concentrations, while Zn and Pb range between low to very low concentrations. (3) The metal enrichment is low compared to the reference lake. The findings show that there are elevated levels in Inre-viken compared to pre-industrial levels. However, identifying the main source of pollution is difficult, because many pollution sources exist in the area. To determine if iron sand is the culprit, further studies are necessary.
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