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1.
Mercury concentrations were measured in samples of peat soils, sediments and clams (Rangia cuneata) from a peatland region of the Albemarle-Panlico Peninsula of North Carolina. Total Hg concentrations in peat cores ranged from 40 to 193 ng g?1 (dw); no depth-related trends were noted. Mercury concentrations in surface sediments from canals draining the peatlands and from the Pungo River that receives this drainage ranged from 8 to 20 ng g?1 (dw). Selective extractions of these peat and sediment samples revealed that the bulk of the Hg was associated with organic matter-associated fractions (particularly humic/fulvic acid bound and organic-sulfide bound fractions). No Hg was detected in the relatively mobile and bioavailable water-soluble or ion-exchangeable fractions. Total Hg concentrations in the soft tissues of clams from the Pungo River ranged from 25 to 32 ng g?1 (ww). No concentrations of methyl Hg above the detection limit of a 25 ng g?1 were measured in soils, sediments, or clams. These data indicate that Hg concentrations in this region are at the low end of the distribution of levels reported for uncontaminated systems and that mining of these peatlands is unlikely to significantly elevate Hg concentrations in the receiving estuarine system.  相似文献   

2.
Variation of mercury (Hg) in sediments and biota from Coatzacoalcos estuary during the dry, rainy and windy seasons was estimated. In sediments, Hg concentrations ranged from 0.07 μg g?1 in site 13 (Ixhuatepec) located upstream, to 1.06 μg g?1 in site 3 (Coatzacoalcos river), located in the industrialized area. Highest enrichment factor (EF) and index of geoaccumulation (I geo) in surficial sediments were 53 and 5.1 respectively. From EF and I geo, it is considered that Coatzacoalcos estuary is from moderately contaminated to contaminated. In most fish species from Coatzacoalcos estuary, the sequence of Hg concentration was liver>muscle>gills. Average Hg concentrations in soft tissue of bivalves ranged from 0.09 μg g?1 in Corbicula fluminea to 0.18 μg g?1 in Polymesoda caroliniana. Biota-sediment accumulation factor (BSAF) ranged from 0.9 in P. caroliniana during the rainy season (site 4) to 3.8 in P. caroliniana from the same site during the windy season.  相似文献   

3.
Estuarine and riverine sediments from fourlocations showing different sediment structures wereanalysed as fresh, thawed and lyophilised samples fortotal mercury (TotHg) and methylmercury (MeHg)concentrations, and results were compared to addresseffects of sample preservation on Hg speciation. TotHg was measured by cold vapour atomic absorptionspectrometry (CVAAS). MeHg was isolated bydistillation and ion-exchange and analysed by coldvapour atomic fluorescence spectrometry (CVAFS) afterpreconcentration on a gold trap. No loss of TotHg norMeHg due to lyophilisation was found. Concentrationsof TotHg and MeHg respectively ranged from 92 to 267ng g-1 dw and 1.1 to 2.9 ng g-1 dw in freshsamples, from 94 to 215 ng g-1 dw and 1.1 to 2.8ng g-1 dw in thawed samples, and from 100 to 256ng g-1 dw and 1.2 to 3.1 ng g-1 dw inlyophilised samples. Lyophilised samples showedbetter homogeneity and better MeHg analysisreproducibility compared with wet samples.  相似文献   

4.
Metal (Cu, Mn, Ni, Zn, Fe) concentrations in marine sediment and zooplankton were investigated in Izmir Bay of the Eastern Aegean Sea, Turkey. The study aimed to assess the levels of metal in different environmental compartments of the Izmir Bay. Metal concentrations in the sediment (dry weight) ranged between 4.26–70.8 μg g?1 for Cu, 233–923 μg g?1 for Mn, 14.9–127 μg g?1 for Ni, 25.6–295 μg g?1 for Zn, 12,404–76,899 μg g?1 for Fe and 38,226–91,532 μg g?1 for Al in the Izmir Bay. Maximum metal concentrations in zooplankton were observed during summer season in the inner bay. Significant relationships existed between the concentrations of certain metals (Al, Fe, Mn and Ni) in sediment, suggesting similar sources and/or similar geochemical processes controlling such metals. Higher concentrations of Cu, Zn and percent organic matter contents were found in the middle-inner bays sediments. Based on the correlation matrix obtained for metal data, organic matter was found to be the dominant factor controlling Cu and Zn distributions in the sediment. In general, mean Cu and Zn levels in the bay were above background concentrations in Mediterranean sediments. Zooplankton metal concentrations were similar to sediment distributions.  相似文献   

5.
We studied the distribution of Hg in sediments, fish, and crayfish in a 60 km reach of the Upper Wisconsin River that formerly received Hg in discharges from pulp and paper mills. The most heavily contaminated strata of sediments were deposited during the 1950s and early 1960s and buried under subsequent deposits; however, surficial sediments remained substantially enriched at certain sites in 1981. Median concentrations of Hg in surficial sediments, adjusted for grain size, were at least 10-fold greater at the main study area than at an upstream reference site. Total concentrations exceeded 1.0 μg g?1 wet weight in axial muscle tissue in only 2 of 173 fish analyzed from the study area; however, historical comparisons revealed that Hg contamination of fish (common carp Cyprinus carpio and walleye Stizostedion vitreum vitreum) and crayfish (Orconectes) in the river had not decreased since the early 1970s. The availability of Hg to biota in this system may be enhanced by rapid methylation of the metal in surficial sediments, despite burial of the most heavily contaminated sediments. Management practices for this river should be designed to prevent conditions favoring mobilization and methylation of Hg in sediments.  相似文献   

6.
The forest floor at high elevation spruce-fir sites from southern Vermont, U.S. to the Gaspé Peninsula, Québec, Canada was sampled and analyzed in 1979 and re-sampled and analyzed in 1996 to study temporal changes in the impacts of atmospheric pollutants. We determined organic matter mass, pH, and concentrations of Al, Ca, Fe, K, Mg, Na, Cd, Cu, Hg, Pb, and Zn for the litter (L = fresh litter plus Oi horizon) and fermentation plus humic horizons (F+H) (= Oe plus Oa horizons) of the forest floor. There were no trends for Al or Fe concentrations in the 1979 or 1996 L along the transect. Several sites had significantly lower Al and Fe values in 1996 than in 1979, likely indicating less mineral soil in the 1996 samples. The 1996 concentrations of Ca in L increased along the transect from 0.22% dry weight (dw) in Vermont to 0.60% dw in Québec. Concentrations of Mg in L were relatively constant along the transect. Neither Ca nor Mg changed at sites from 1979 to 1996, indicating unchanged base status. Concentrations of Cd did not vary spatially along the transect but decreased at all sites from 1979 to 1996. Cu and Zn did not vary spatially or with time. In 1979, the concentration of Hg in L ranged between 150 and 300 μg kg?1 dw, with no spatial gradient. By 1996, Hg concentrations were 25 to 50% lower in L, with decreases generally proportional to the concentration in 1979. The concentration of Pb in 1979 L decreased significantly from 200 mg kg?1 dw in southern Vermont to 60 mg kg?1 dw in Québec. By 1996, the Pb concentration in L ranged between 32 and 66 mg kg?1 dw with no spatial trend along the transect. Decreases in Pb concentrations at sites were proportional to the absolute value in 1979. The concentrations of Cd, Hg, and Pb have declined in litter from 1979 to 1996, indicating a decline in atmospheric deposition. Higher Hg and Pb accumulation rates to the southwest are suggested for the past as indicated by (F+H) concentrations and inventories of Hg and Pb. The decline of Pb in L is consistent with the decreased use of leaded gasoline starting in the 1970s; the declines in Cd and Hg probably reflect lower emissions over the same period. Declining concentrations of Cd, Hg, and Pb in L parallel those documented in recent lake and peat sediments in the northeastern United States.  相似文献   

7.
The mobility of mercury (Hg) deposited on soils controls the concentration and toxicity of Hg within soils and in nearby streams and lakes, but has rarely been quantified under field conditions. We studied the in situ partitioning of Hg in the organic top layer (mor) of podsols at two boreal forest sites differing in Hg deposition and climatic regime (S. and N. Sweden, with pollution declining to the north). Soil solution leaching from the mor layer was repeatedly sampled using zero-tension lysimeters over 2 years, partly in parallel with tension lysimeters. Concentrations of Hg and dissolved organic carbon (DOC) were higher while pH was lower at the southern site (means ± SD: Hg?=?44?±?15 ng L?1, DOC?=?63.0?±?31.3 mg L?1, pH?=?4.05?±?0.53) than at the northern site (Hg?=?22?±?6 ng L?1, DOC?=?41.8?±?12.1 mg L?1, pH?=?4.28?±?0.43). There was a positive correlation over time between dissolved Hg and DOC at both sites, even though the DOC concentration peaked during autumn at both sites, while the Hg concentration remained more constant. This correlation is consistent with the expected strong association of Hg with organic matter and supports the use of Hg/C ratios in assessments of Hg mobility. In the solid phase of the overlying Of layer, both Hg concentrations and Hg/C ratios were higher at the southern site (means ± SD: 0.34?±?0.06 μg g?1 dw and 0.76?±?0.14 μg g?1 C, respectively) than at the northern site (0.31?±?0.05 μg g?1 dw and 0.70?±?0.12 μg g?1 C, respectively). However, concentrations in the solid phase differed less than might be expected from the difference in current atmospheric input, suggesting that the fraction of natural Hg is still substantial. At both sites, Hg/C ratios in the upper half of the mor layer were only about two thirds of those in the lower half, suggesting that the recent decrease in anthropogenic Hg deposition onto the soil is offset by a natural downward enrichment of Hg due to soil decomposition or other processes. Most interestingly, comparison with soil leachate showed that the average Hg/C ratios in the dissolved phase of the mor layers at both sites did not differ from the average Hg/C ratios in the overlying solid organic matter. These results indicate a simple mobilisation with negligible fractionation, despite differences in Hg deposition patterns, soil chemistry and climatic regimes. Such a straight-forward linkage between Hg and organic matter greatly facilitates the parameterisation of watershed models for assessing the biogeochemical fate, toxic effect and critical level of atmospheric Hg input to forest soils.  相似文献   

8.
Purpose

Run-off from industrial and agricultural activities has continued to be a major source of organohalogenated contaminants (OHCs) in the environment. Swartkops (SWE) and Sundays Estuaries (SDE) located in the city of Port Elizabeth, South Africa, were selected for this study because of their proximity to industrial and agricultural activities.

Materials and methods

In this study, we determined the levels, seasonal occurrence as well as the ecological risk monitoring of 18 organochlorine pesticides (OCPs), 17 polychlorinated biphenyls (PCBs) and six polybrominated diphenyl ethers (PBDEs) in the sediments of SWE and SDE using a gas chromatograph coupled with a micro electron capture detector.

Results and discussion

HCHs, BDE-17, tri- and tetra-CBs dominated the OHC profiles in sediments of both estuaries. The respective concentration ranges of OCPs, PCBs and PBDEs in SDE sediment were 0.06–0.93 μg g?1 dw, 0.08–1.71 μg g?1 dw and 0.08–32.41 ng g?1 dw while that of SWE in that order were 0.10–4.70 μg g?1 dw, 0.07–3.80 μg g?1 dw and 0.11–130.21 ng g?1 dw. The high concentrations of OHCs in SWE may be due to the high usage of its surrounding area for industrial activities. The concentrations of all OHCs with exception of PCBs were higher in spring for both estuaries probably due to the heavy rain experienced during spring season. Cluster analysis and spatial distribution of OHCs indicated that samples around the Motherwell Canal in the SWE were more polluted. Total organic carbon (TOC) was strongly correlated with most OHCs in SWE revealing that TOC controls the sorption of OHCs in this estuary. Risk analysis showed that most sampling points had PCBs and HCHs concentration greater than their respective sediment quality guideline (SQGL) indicating a high risk to benthic species in SDE and SWE.

Conclusions

Samples collected from the SWE were more polluted than those collected from the SDE probably due to the extensive use of the catchment of SWE for industrial activities. In comparison with SQGL, most sampling points had PCBs and HCHs concentrations greater than their respective ERL and TEL values, indicating the potential risk to biota in SDE and SWE. Thus, an urgent need to manage and mitigate the OHCs concentrations in these estuaries is recommended.

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9.
During one year, samples from eight drainage lakes, seven run-off stations and three deposition sites from various geographical areas in Sweden were collected and analyzed for methyl Hg (MeHg) and total Hg (Hg-tot). The MeHg concentrations ranged from 0.04 to 0.64 ng L?1, 0.04 to 0.8 ng L?1, and <0.05 to 0.6 ng L?1 in run-off, lake water and rain water, respectively. The corresponding Hg-tot concentrations were found in the range 2 to 12 ng L?1, 1.35 to 15 ng L?1, and 7 to 90 ng L?1, respectively. A Hg-tot level of about 60 ng Hg L?1 was found in throughfall water. The MeHg and Hg-tot concentrations are positively correlated in both run-off and lake water, but not in rain and throughfall water. A strong positive correlation between the MeHg, as well as the Hg-tot concentration, and the water color is observed in both run-off and lake waters, which suggests that the transport of MeHg and other Hg fractions from soil via run-off water to the lake is closely related to the transport of organic substances; and is a consequence of the biogeochemical processes and the water flow pathway. The ratio between the mean values of MeHg and Hg-tot seems to be an important parameter, with an indicated negative coupling to the mean value of pH for run-off water, but a strong positive correlation to Hg-content in fish, the ratio between the area of the catchment and the lake, as well as to the retention time of lake.  相似文献   

10.
Aim and Background  Little data are available on the levels of polycyclic aromatic hydrocarbons (PAHs) in the sediments of the Mediterranean Sea Coast of Egypt in general and the Alexandria coastal zone in particular. It was therefore deemed necessary to set up a monitoring programme to determine the current concentrations of PAHs in bottom sediments, and to identify any area where high concentrations of these potential hazardous contaminants were present in the Western Harbour of Alexandria. Methods  The composition, distribution and the source of PAHs in surficial sediments of the harbour were investigated. To document the spatial PAH input, surficial sediment samples from 23 locations throughout the harbour were analysed. as]Results and Discussion The total PAH load determined in the surficial sediment samples ranged from 8 to 131150 ng g1 dry wt, generally with most of the samples having total concentrations of PAHs greater than 5000 ng g1 dry weight. The highest concentration of total PAHs was recorded in sediments of the inner harbour. Ratio values of specific compounds such as phenanthrene to anthracene, fluoranthrene to pyrene, methyl-phen-anthrene to phenanthrene, methyl-dibenzothiophenes to dibenzothiophenes, alkylated to non-alkylated and high molecular weight to low molecular weight PAH, were calculated to evaluate the possible source of PAH contamination in the harbour sediments. Conclusions  Two main sources of PAH in the study area have been found: pyrolytic and petrogenic. Interferences of rather petrogenic and pyrolytic PAH contaminations were noticed for most samples. The dominant sources of PAH appear to be the combustion processes through run-off, industrial and sewage discharges, and atmospheric input. The concentrations of PAHs were generally above levels expected to cause adverse biological effects. Recommendations and outlook  Information from this study and any other relevant studies should be useful in designing future strategies for environmental protection and management of the harbour.  相似文献   

11.
The sources and concentrations of total mercury (total Hg) and methylmercury (MeHg) in the upper catchment of the Lake Gordon/Lake Pedder system in Tasmania, Australia were investigated. The catchment area, which contains over 50% wetlands, is located in a temperate region with no obvious point sources of mercury. Surface waters in the region had concentrations of total Hg ranging from 1.2 to 14.4 ng L-1 and MeHg from < 0.04 to 1.4 ng L-1. MeHg concentrations were seasonally dependent, with the highest concentrations occurring in summer. Sediments/soils in the catchment had concentrations of total Hg ranging from 4.0 to 194 ng g-1 and MeHg from <0.02 to 20.1 ng g-1. The low concentrations of total Hg confirmed that this region is pristine as regards mercury and has no geological enrichment of total Hg. The highest total Hg and MeHg concentrations in both sediment/soils and waters were found in bogs whereas the lowest concentrations typically occurred on the wetlandplains. MeHg concentrations, in bog and swamp sediments were correlatedwith the organic matter content (r = 0.942, P < 0.001). Acid volatile sulfide (AVS) measurements indicate that in most sediments AVS was greater than total Hg. Given the high reactivity of inorganic mercury and sulfide, this suggests that most of the particulate mercury in sediments is present as mercuric sulfide. The yield of MeHg from the catchment was estimated to be 3.2 mg ha-1 yr-1 and is higher than published rates measured in non-contaminated temperate catchments in the northern hemisphere. The higher yield was attributed to the generally warmer climatic conditions that favour net methylation and the relatively high rainfall (2–3 m yr-1) of the region, which supplies reactive inorganic mercury to the active zones ofmercury methylation and also flushes MeHg from the catchment.  相似文献   

12.
We analyzed surface waters from 30 Wisconsin lakes and rivers for total mercury ([Hg]T) and total suspended particulates (TSP) on a state-wide basis with trace-metal ‘ultraclean’ techniques. Mercury concentrations ranged from 0.3 to 2.9 ng L?1 in lakes and from 0.7 to 8.9 ng L?1 in rivers. TSP concentrations ranged from 0.9 to 6.6 mg L?1 in lakes and from 3.1 to 31.4 mg L?1 in rivers. Spatial trends were weak; however, [Hg] T was generally higher in the spring than in the autumn of 1991. Total mercury concentration was weakly dependent on TSP with the coefficient of determination (r 2) ranging 0.06 to 0.49 across seasonal and geophysical differences.  相似文献   

13.
A sampling and analysis program has been completed between 1995 and 1998 in order to determine mercury concentrations in water, sediments, soils and fish in the Piracicaba river basin, one of the most populated and industrialized regions in Brazil. In sediment, the average Hg concentrations varied between 33 ± 17 ng g?1 and 106 ± 78 ng g?1, in samples collected during the rainy and dry season, respectively. The same averages were also found for soil samples (35 ± 14 and 109 ± 61 ng g?1). In water, the total Hg concentration varied between < 1.1 and 24.0 ng L?1. In piscivore fish, up to 943 μ g Hg kg?1 was found. Our results show that all compartments undergo Hg contamination, in view of the levels found in pristine environments. Water contamination seems to be due mainly to diffuse processes of soil erosion and suspension of river bed sediment during the rainy season. Also untreated wastewaters generated by industrial activities and from domestic sewage appear to be potential non-point sources in the most industrialized and populated part of the basin. On the other hand, atmospheric transport of mercury originating from the Campinas Metropolitan Region could be another source of mercury contamination, especially in the basin headwaters.  相似文献   

14.
Lakes within 20 km of Sudbury, Ontario, have significantly higher Cd concentrations in surface waters (geometric mean 122 ng L?1; n = 7) than lakes elsewhere in central Ontario (10.8 ng L?1; n = 57). Cadmium concentrations in water from lakes beyond the Sudbury halo were negatively correlated (r = 0.797; p < 0.001) with pH. A weak correlation between fluoride and Cd concentrations leads to speculation that some Cd may be mobilized from watersheds with Al. Cadmium concentrations in littoral sediments are not elevated near Sudbury. The geometric mean Cd concentration of littoral sediments in central Ontario lakes is 0.08 mg Cd kg?1 dry mass (n = 75). Cadmium concentrations in littoral sediments are strongly correlated with sediment loss on ignition (r = 0.860; p < 0.001). After correction for differences in organic content, littoral sediments are less enriched with Cd than profundal sediments, as reported in the literature. The difference between littoral and profundal sediments, and the sensitivity of Cd concentrations in water to pH, may be due to the importance of Cd binding by Fe/Mn hydrous oxides in the profundal zone, while organic matter binds Cd in the littoral zone. The lack of sensitivity of Cd concentrations in littoral sediments to acidification may be due to the incorporation of much of the Cd in those sediments into organic particulates.  相似文献   

15.
Litterfall can be an important flux of mercury (Hg) to soils in forested landscapes, yet typically the only available data to evaluate Hg deposition is from precipitation Hg monitoring. Litterfall was collected at 39 sampling sites in two small research watersheds, in 2003 and 2004, and analyzed for total Hg. Four vegetation classes were designated in this study as hardwoods, softwoods, mixed and scrub. The mean litter Hg concentration in softwoods (58.8 ± 3.3 ng Hg g?1 was significantly greater than in mixed (41.7 ± 2.8 ng Hg g?1 and scrub (40.6 ± 2.7 ng Hg g?1, and significantly lower than in hardwoods (31.6 ± 2.6 ng Hg g?1. In contrast, the mean weighted litter Hg flux was not significantly different among vegetation classes. The lack of a significant difference in litter Hg flux between hardwoods and softwoods was attributable to the large autumnal hardwood litter Hg flux being balanced by the higher softwood litter Hg concentrations, along with the higher chronic litterfall flux throughout the winter and spring in softwoods. The estimated annual deposition of Hg via litterfall in Hadlock Brook watershed (10.1 μg m?2 and Cadillac Brook watershed (10.0 μg m?2 was greater than precipitation Hg deposition and similar to or greater than the magnitude of Hg deposition via throughfall. These results demonstrate that litterfall Hg flux to forested landscapes can be at least as important as precipitation Hg inputs.  相似文献   

16.
Bone fluoride concentration was measured in field voles (Microtus agrestis) trapped throughout a year at a moderately polluted site 1 km south of an Al reduction plant at Holyhead, Anglesey. Fluoride values ranged from 300 to 4800 μg g?1, with a mean of 2074 μg g?1 and increased with age as judged by dried eye-lens weight and body weight. At a heavily polluted site about 250 m from the pot-room of the reduction plant field voles had bone fluoride concentrations which ranged from 910 to 11000 μg g?1 with a mean of 7148 μg g?1. Wood mice (Apodemus sylvaticus) at this same location had a mean bone fluoride concentration of 8430 μg g?1 and ranged from 1800 to 17 200 μg g?1. The difference in mean bone fluoride concentration between these two species at this location was not significant (P > 0.1). A sample of field voles from presumed unpolluted sites in other parts of Britain had bone fluoride concentrations which ranged from 23 to 540 μg g?1 with a mean of 168 jig g?1. There was a high positive correlation (r > 0.97) between fluoride concentrations in different parts of field vole skeletons. There was no correlation between bone fluoride concentration in field voles and their femur diameters (r < 0.2).  相似文献   

17.
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18.
To help expand our global perspective on trace metal contamination, concentrations of Cu, Fe, Hg, Mn, Ni, Pb, and Zn were determined for sediments from the Ebrie Lagoon in the Ivory Coast, a developing West African nation. Excess loading of several metals, especially Hg, Pb, and Zn was found at several sites. The maximum concentration of Hg measured in sediments from the Ebrie Lagoon (2250 ng g?1) is about 30 times greater than natural levels. Similarly, Pb and Zn concentrations for the Ivorian lagoonal sediments are as high as 250 and 560 μg g?1, respectively, showing sizeable anthropogenic inputs. Trace metal sources to the Ebrie Lagoon include untreated sewage and industrial wastes.  相似文献   

19.
Fifty four samples of surface sediments (1-cm of thickness) and a gravity core of 154-cm long were collected in the Vigo Ria, NW of Iberian Peninsula. In the laboratory the sediments were oven dried at 40°C, desegregated, homogenised and analyzed for total Hg, monomethylmercury (MMHg), Al, and particulate organic carbon (POC). Mercury in sediments varied within a broad range: 0.09 to 8.9 nmol g?1 the higher concentrations being found in the shipyards and docks areas of Vigo port (southern–middle Ria zone). No correlation was found between Hg and POC. The good exponential correlation between total Hg and Al levels suggests that Hg is closely associated with the fine fraction of sediments. Monomethylmercury concentrations in surface sediments ranged between <1.4 (DL) and 8.5 pmol g?1 being the spatial distribution similar to that observed for total Hg. The lack of correlations MMHg–Al and MMHg–POC suggests that in situ processes of methylation/demethylation are responsible for MMHg distribution rather than the sediment characteristics. Additionally, these processes appear mercury-dependent only for Hg concentrations above 2.5 nmol g?1. On the basis of these results it was estimated that 155 kg of Hg (0.1% MMHg) are present in the surface sediments of Vigo Ria, being 61% of anthropogenic origin.  相似文献   

20.
Rencz  A. N.  O'Driscoll  N. J.  Hall  G. E. M.  Peron  T.  Telmer  K.  Burgess  N. M. 《Water, air, and soil pollution》2003,143(1-4):271-288
This study investigates the ranges and spatial variation ofmercury in various media in the wetland ecosystems ofKejimkujik Park, Nova Scotia. Mercury concentrations infive-year-old yellow perch (age based on regression analysesof existing data) ranged from 0.12–0.72 μgg-1(wet weight basis) in 24 lakes. Mercury concentrations inred maple ranged from 5 to 41 ng g-1 and levels inwhite pine ranged from 5 to 58 ng g-1, dry weight.Concentrations of total mercury were found to besignificantly higher in epiphytic lichens (maximum of 660 ngg-1) and in feather mosses (maximum of 395 ng g-1)compared to vascular species. The soil Ah horizon exhibitsthe highest concentrations for both mercury and gold, withmaximum values of 466 and 42.8 ng g-1 respectively;whereas the C-horizon appears to host the most Zn (maximum209.9 μg g-1). Lake water pH and dissolved organic carbon (DOC) were thevariables most highly correlated with mercury in lake watersand yellow perch. No correlations were observed betweenmercury in terrestrial components and mercury in yellowperch; however, mercury in yellow perch was correlated withP in leaf tissues of both red maple and white pine. Theimportance of understanding linkages between terrestrial andaquatic ecosystems is emphasized through this study.  相似文献   

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