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1.
Di Beneditto AP Bittar VT Camargo PB Rezende CE Kehrig HA 《Archives of environmental contamination and toxicology》2012,62(2):264-271
The present study raised the hypothesis that the trophic status in a tropical coastal food web from southeastern Brazil can
be measured by the relation between total mercury (THg) and nitrogen isotope (δ15N) in their components. The analysed species were grouped into six trophic positions: primary producer (phytoplankton), primary
consumer (zooplankton), consumer 1 (omnivore shrimp), consumer 2 (pelagic carnivores represented by squid and fish species),
consumer 3 (demersal carnivores represented by fish species) and consumer 4 (pelagic-demersal top carnivore represented by
the fish Trichiurus lepturus). The values of THg, δ15N, and trophic level (TLv) increased significantly from primary producer toward top carnivore. Our data regarding trophic
magnification (6.84) and biomagnification powers (0.25 for δ15N and 0.83 for TLv) indicated that Hg biomagnification throughout trophic positions is high in this tropical food web, which
could be primarily related to the quality of the local water. 相似文献
2.
Biomagnification of Trace Elements in the Aquatic Food Web in the Mekong Delta,South Vietnam Using Stable Carbon and Nitrogen Isotope Analysis 总被引:1,自引:0,他引:1
Ikemoto T Tu NP Okuda N Iwata A Omori K Tanabe S Tuyen BC Takeuchi I 《Archives of environmental contamination and toxicology》2008,54(3):504-515
In the present study, we report the concentrations of 21 trace elements (V, Cr, Mn, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd,
Sn, Sb, Cs, Ba, Hg, Tl, Pb, and Bi), as well as the results of the analysis of stable carbon and nitrogen isotopes, of the
various biota that make up the food web in the main stream of the Mekong Delta near Can Tho, South Vietnam. A significant
trophic level-dependent increase was found in concentrations of Se, Rb, and Hg with increasing δ15N, indicating that an overall biomagnification of these elements occurred. However, the increase of Hg concentration per trophic
level was lower than in previous studies. In contrast, the concentration of Mn showed an opposite trend in the food web of
the Mekong Delta. In addition to these overall trends, the present study revealed that the biomagnification profiles of trace
metals differ between crustaceans and fishes; concentrations of Mn, Cu, Zn, As, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, and Pb were
significantly higher in crustaceans, whereas fishes showed higher concentrations of Cr, Rb, and Hg (trophic level determined
by δ15N). The differences in the biomagnification profile between the major taxa might be attributed to differences in metal accumulation
and in detoxification abilities such as possessing a metal-binding protein, e.g., metallothionein (MT). 相似文献
3.
Salvatrice Vizzini Valentina Costa Cecilia Tramati Paola Gianguzza Antonio Mazzola 《Archives of environmental contamination and toxicology》2013,65(4):642-653
Trace element accumulation is particularly important in coastal and transitional environments, which act as contaminant buffers between the continental and marine systems. We compared trace element transfer to the biota in two locations with different open-sea exposures in a semi-enclosed marine coastal area (Stagnone di Marsala, Sicily, Italy) using isotopically reconstructed food chains. Samples of sediment, macroalgae, seagrasses, invertebrates, fish, and bird feathers were sampled in July 2006 and analysed for stable carbon and nitrogen isotopes (δ13C, δ15N) and trace elements (arsenic [As], cadmium [Cd], total mercury [THg], and lead [Pb]). Trophic magnification factors were calculated through the relationships between trace elements and δ15N in consumers. As and Pb were greater in organic matter sources (sediments and primary producers), whereas Cd and THg were greater in bird feathers. At the food chain level, an insignificant trophic transfer was found for all elements, suggesting biodilution rather than biomagnification. Sediments were more contaminated in the location with lower open-sea exposure. Macroalgae and seagrasses overall mirrored the spatial pattern highlighted in sediments, whereas differences between the two locations became further decreased moving toward higher trophic levels, indicating that trophic transfer of sediment and macrophyte-bound trace elements to the coastal lagoon food chain may be of relatively minor importance. 相似文献
4.
Cheng Z Liang P Shao DD Wu SC Nie XP Chen KC Li KB Wong MH 《Archives of environmental contamination and toxicology》2011,61(3):491-499
This is the first study to investigate the rate of mercury (Hg) biomagnification in the aquaculture pond ecosystem of the
Pearl River Delta (PRD), China, by analyzing total mercury (THg) and methyl mercury (MeHg) concentrations in various species
of fish at different trophic levels (TLs). Species representing a gradient of trophic positions in the aquaculture pond food
chains were chosen for analyzing THg and MeHg concentrations. In this study, there were two kinds of the aquaculture pond
food chains: (1) omnivorous (fish feeds, zooplankton, grass carp [Ctenopharyngodon idellus], and bighead carp [Aristichthys nobilis]) and (2) predatory (zooplankton, mud carp [Cirrhina molitorella], and mandarin fish [Siniperca kneri]). Bighead carp and mandarin fish had the highest MeHg and THg concentrations, i.e., an order of magnitude higher than other
species, in their respective food chains. More than 90% of the THg concentrations detected in bighead carp, mandarin fish,
and mud carp were in the methylated form. In this study, %MeHg increased with TLs and MeHg concentrations, reflecting that
MeHg is the dominant chemical species of Hg accumulated in higher concentrations in biota, especially biota associated with
higher TLs in the food chains. The trophic magnification factors were 2.32 and 2.60 for MeHg and 1.94 and 2.03 for THg in
omnivorous and predatory food chains, respectively, in PRD. Hg concentrations in fish tissue correlated to Hg levels in the
ambient environment, and sediment seemed to be the major source for Hg accumulated in fish. In addition, feeding habit also
affected Hg accumulation in different fish species. Four significant linear relationships were obtained between log-THg and
δ15N and between log-MeHg and δ15N. The slope of the regression equations, as biomagnification power, was smaller in magnitude compared with those reported
for temperate and arctic marine and freshwater ecosystems, indicating that THg and MeHg biomagnifications were lower in this
PRD subtropical aquaculture pond ecosystem. This was probably due to low Hg bioavailability at lower TLs as well as individual
feeding behavior of fish. 相似文献
5.
Kojadinovic J Le Corre M Cosson RP Bustamante P 《Archives of environmental contamination and toxicology》2007,52(3):418-430
This work aimed to use seabirds as bioindicators of trace element levels in the tropical waters and food webs of the Western
Indian Ocean. The accumulation patterns of selected toxic (Cd and Hg) and essential (Cu, Fe, Mn, Se, and Zn) elements were
determined in liver, kidney, and pectoral muscle of 162 marine birds belonging to 3 species collected in Reunion Island between
2002 and 2004. These pelagic seabirds belong to the following species: Barau’s Petrel (Pterodroma baraui), Audubon’s Shearwater (Puffinus lherminieri bailloni), and White-Tailed Tropicbird (Phaethon lepturus). Hg levels were also measured in breast feathers. Highest mean kidney Cd and liver Hg levels (respectively, 27.79 ± 13.78 μg.g
−1 dry weight (dw) and 24.31 ± 14.13 μg.g
−1 dw) were found in the squid-eating Barau’s Petrel. Barau’s Petrel feather Hg levels fell in the range of 0.6 to 2.7 μg.g−1 dw previously reported for other petrels and shearwaters. The values of the other elements were also in the same range as
those previously reported in the published literature concerning related seabirds, although Se and Zn burdens in the Reunion
birds were among the highest values. Levels of Zn, Fe, and, to a lesser extent, Cu appeared to be regulated in seabird tissues.
Uptake and pathways of metabolism and storage seemed to be similar for the five essential elements. The reproductive status
of the bird did not seem to affect element levels, which, moreover, were not significantly different between male and female
birds. However, trace elements in sampled birds varied according to the tissue considered, the age of the animal, and its
species. Diet was seemingly a major influencing factor. Health status also appeared to have an impact on element levels. 相似文献
6.
Effects of Diet Composition and Trophic Structure on Mercury Bioaccumulation in Temperate Flatfishes
Eric J. Payne David L. Taylor 《Archives of environmental contamination and toxicology》2010,58(2):431-443
The summer flounder Paralichthys dentatus and winter flounder Pseudopleuronectes americanus support valuable fisheries along the northeastern United States. The importance of these flatfish as a human dietary resource
indicates they are potential sources of mercury (Hg) to fish-consuming citizens. In this study, summer flounder (SF) and winter
flounder (WF) were collected from the Narragansett Bay (Rhode Island, USA) and were measured for total Hg burden in whole-body
or dorsal muscle tissue. Interspecies differences in Hg contamination were analyzed relative to flounder body size, age, and
Hg content of preferred prey. Stable isotope signatures were also used to elucidate the effect of trophic processes on Hg
accumulation in the estuarine food web. The mean Hg content of SF exceeded concentrations measured in WF across multiple life-history
stages (0.039–0.100 and 0.016–0.029 mg Hg/kg wet weight for SF and WF, respectively), and observed values for both species
were lower than the US Environmental Protection Agency regulatory threshold of 0.3 mg Hg/kg wet weight. Total Hg concentrations
were also positively correlated with flounder age and length, verifying that both flatfish bioaccumulate Hg. SF accumulate
Hg at an accelerated rate, however, owing to this species consuming Hg-enriched prey (teleosts, squid, and macrocrustaceans;
mean Hg content = 0.023 mg Hg/kg wet weight), whereas WF feed on prey with low Hg levels (amphipods and polychaetes; mean
Hg content = 0.013 mg Hg/kg wet weight). The positive correlation observed between mean biota Hg content and stable nitrogen
(δ15N) isotope signatures further indicates that Hg is trophically transferred through the food web, and higher trophic level
organisms (i.e., enriched δ15N) have increased Hg concentrations. Therefore, results from this study suggest that dietary preference and trophic structure
are the main factors affecting Hg bioaccumulation in the estuary. Total Hg concentrations of flatfish from the Narragansett
Bay, however, do not necessarily reflect coastwide contamination patterns. This reinforces the importance of having research
conducted at sufficiently small spatial scales, including the local assessment of Hg contamination for the purpose of issuing
state consumption advisories. 相似文献
7.
Kojadinovic J Bustamante P Le Corre M Cosson RP 《Archives of environmental contamination and toxicology》2007,52(3):431-440
Seabird tissues collected between 2002 and 2004 from Barau’s Petrel (Pterodroma baraui), Audubon’s Shearwater (Puffinus lherminieri bailloni), and White-Tailed Trop icbird (Phaethon lepturus) colonies on Reunion Island were analyzed for metallothioneins (MTs) and trace element content. The subcellular distribution
between soluble and insoluble fractions of Cd, Cu, Fe, Mn, Se, and Zn was determined in liver and kidney. In both, the soluble
fraction of the cell concentrated most of the Cd and Se, whereas Fe, Mn, and Zn were preferentially accumulated in the insoluble
fraction. The distribution of these elements varied with the tissue, age of the bird, and species. Furthermore, the distributions
of Fe and Mn were somewhat influenced by the bird’s physical condition. MT levels were measured in the soluble fraction after
heat denaturation. The levels of these proteins varied from 5.5 ± 2.7 mg.g−1 dry weight (dw) to 11.4 ± 6.2 mg.g−1 dw depending on the species and the tissue considered. MT levels were significantly different between liver and kidney only
in the White-Tailed Tropicbird. In the three species, MT levels in kidney were significantly higher in adult than juvenile
birds. The bird’s weight also had an influence on hepatic and renal MT levels, but not the sex nor the reproductive status.
The implication of MTs in Cu and Zn homeostasis and Cd and Hg detoxification are discussed. In addition, clues on Hg regulation
by Se were found, especially in Barau’s Petrel, where the levels of these two elements were significantly correlated. 相似文献
8.
Xiaoyu Xu Michael C. Newman Mary C. Fabrizio Lian Liang 《Archives of environmental contamination and toxicology》2013,65(3):510-520
Total mercury (THg) and methylmercury (MHg) concentrations and determents of mercury (Hg) accumulation were examined for muscle tissues of 10 finfish from the lower Chesapeake Bay (LCB) and its tributaries. There was no suggestion of potential human harm from Hg due to LCB fish consumption: None of the sampled fish had THg concentrations approaching the United States Environmental Protection Agency human health screening value. Hg concentrations in different fish species generally increased with the increasing stable isotope of nitrogen 15 (δ15N) but not the stable isotope of carbon 13 (δ13C), thus suggesting that trophic position but not dietary carbon source is a dominant determinant. An MHg biomagnification model was built to estimate a food web magnification factor of approximately 10-fold increase per trophic level. Based on otolith strontium-to-calcium ratios, Atlantic croaker inhabiting less saline waters might accumulate more Hg than those inhabiting more saline waters. The SAS mixed procedure identified significant positive intraspecies relationships between MHg concentration and δ13C for summer flounder, weakfish, American eel, Atlantic croaker, and spot. 相似文献
9.
Ruiz-Fernández AC Frignani M Tesi T Bojórquez-Leyva H Bellucci LG Páez-Osuna F 《Archives of environmental contamination and toxicology》2007,53(2):159-167
210Pb-derived sediment accumulation rates, as well as a suite of geochemical proxies (Al, Fe, δ13C, δ15N), were used to assess the time-dependent variations of C, N, and P fluxes recorded in two sediment cores collected at Ohuira
Lagoon, in the Gulf of California, Mexico, during the last 100 years. Sedimentary C, N, and P concentrations increased with
time and were related to land clearing, water impoundment, and agriculture practices, such as fertilization. C:N:P ratios
and δ13C suggested an estuarine system that is responsive to increased C loading from a N-limited phytoplankton community, whereas
δ15N values showed the transition between an estuarine-terrestrial to an estuarine-more marine environment, as a consequence
of the declining freshwater supply into the estuary due to the channeling and impoundment of El Fuerte River between 1900
and 1956. The recent increases in nutrient fluxes (2- to 9-fold the pre-anthropogenic fluxes of C and N, and 2 to 13 times
for P) taking place in the mainland from the 1940s, were related to the expansion of the intensive agriculture fields and
to the more recent development of shrimp farming activities. 相似文献
10.
J Yoshinaga T Suzuki T Hongo M Minagawa R Ohtsuka T Kawabe T Inaoka T Akimichi 《Ecotoxicology and environmental safety》1992,24(1):37-45
The relationships among element concentrations (Na, Mg, Al, P, K, Ca, Cr, Fe, Mn, Cu, Zn, Sr, total Hg, organic Hg, inorganic Hg, Pb) and stable carbon and nitrogen isotope ratios (13C/12C and 15N/14N) in animals consumed by the people called Gidra, who inhabit the lowland of Papua New Guinea, were examined. Animals analyzed included mammal, bird, fish, shellfish, reptile, crustacean, and insect. Highly significantly positive correlations were observed between total Hg concentrations and 15N/14N (r = 0.796), between organic Hg concentrations and 15N/14N (r = 0.781), and between inorganic Hg concentrations and 15N/14N (r = 0.739). This was interpreted to indicate that Hg was an element which accumulates in animals along the food chain. Based on the regression function of Hg on delta 15N, the bioconcentration factor for total, organic, and inorganic Hg was estimated to be 5. 相似文献
11.
Xu J Xie P Zhang M Zhou Q Zhang L Wen Z Cao T 《Bulletin of environmental contamination and toxicology》2007,79(3):323-326
We investigated differences in δ15N of seston and icefishes from seven freshwater ecosystems with different trophic states in China. An increase of seston δ15N values was accompanied by an increase of total nitrogen and phosphorus concentrations. Significantly positive correlations
were observed between δ15N of icefishes and δ15N of seston, total nitrogen and phosphorus concentrations. This study demonstrated that icefishes could be preferred indicators
of anthropogenic contamination in test systems because they integrated waste inputs over long time periods and reflected the
movement of waste through the pelagic food chain. 相似文献
12.
L. Bendell-Young J. Chouinard F. R. Pick 《Archives of environmental contamination and toxicology》1994,27(2):186-194
Concentrations of Zn, Cu, Al, Fe, and Mn were determined in Chironomidae (Diptera) larvae sampled from three sites within eight peatlands, located in south-central Ontario, Canada. The eight peatlands displayed a range in pH and alkalinity and were classified abiotically (i.e., chemically, hydrologically) and biotically (i.e., dominant vegetation present) as mineral-poor, moderately poor, or as mineral-rich fen. Surface peats of mineral-poor fens were distinct from those of moderately poor and mineral-rich fens; mineral-poor fens contained higher concentrations of organic matter with low concentrations of easily reducible Mn vs. the moderately poor and mineral rich fens. A one-way nested ANOVA indicated that chironomid metal concentrations were peatland dependent (P<0.05). To determine if differences in chironomid metal concentrations among the peatlands could be related to peat geochemistry, an R2 MAX procedure using peat geochemistry as the independent variable and chironomid metal concentrations as the dependent variable was applied. Peat geochemistry was defined as concentrations of peat organic matter, reducible Fe (Fe oxides), reducible Mn (Mn oxides) and easily reducible metal (where metal = Zn, Cu, Al, Mn and Fe), and reducible metal and organically bound metal. Chironomids from mineralrich peatlands, i.e., peatlands low in organic matter with high concentrations of reducible Mn and Fe or easily extractable metal contained greater concentrations of Zn, Mn, and Fe vs. chironomids sampled from mineral poor peatlands, i.e., peatlands with high concentrations of peat organic matter and low concentrations of reducible Mn or easily extractable metal. In contrast, Cu concentrations were greatest in larvae sampled from mineral-poor vs. mineral-rich peatlands. Aluminum larvae concentrations were independent of peat geochemistry. We suggest that bioavailability of metals such as Zn, Fe, and Mn will be greater to invertebrates inhabiting mineral rich vs. mineral poor fens, whereas greater chironomid Cu concentrations will be found in chironomids sampled from mineral poor fens. Differences in metal availability to invertebrates among peatland types has important implications when comparing the impact of contaminant transfer to higher trophic levels among different types of peatlands. 相似文献
13.
Antonio Rodríguez Martin Acosta Lourdes Mugica Sergi Ferrer Carolina Sanpera Lluis Jover 《Archives of environmental contamination and toxicology》2013,65(1):24-32
The Birama Swamp is the second largest wetland in the Caribbean region and it is inhabited by large populations of waterbirds. Here we report, for the first time, the foraging ecology and pollutant levels of three Ardeidae species: Cattle egret (Bubulcus ibis), Snowy egret (Egretta thula), and Tricolored heron (E. tricolor) breeding in this wetland using stable-isotope (δ 15N and δ 13C) and trace elements [mercury (Hg), lead (Pb), and selenium (Se)] analysis of chick feathers. Our results showed that individuals from all species occupied similar trophic levels. However, we found significant differences for δ 13C, with the highest values in cattle egret indicating its use of terrestrial habitats and a generalist and opportunist behavior. No significant differences were found for Pb among species. Yet, Hg levels were greater and similar in tricolored heron and snowy egret than in cattle egret, which was associated with their greater use of aquatic environments. Snowy egret had the lowest values of Se differing significantly with the other two species suggesting a different relative use of prey type. Modeling log-Hg concentration in relation to δ 15N and δ 13C showed an independent and significant relationship among species but without interaction with species level indicating that within a particular species, higher Hg levels were associated with higher δ 15N values. There was no interaction between δ 15N and δ 13C in the general linear models for Se and Pb in all species. We found an association between δ 15N and species in Pb for snowy egret. The foraging habitat use of these species and the low levels of pollutants, which are lower than in other similar habitats in other areas of the world, indicated that there is not risk of negative effects in juvenile birds of the Birama Swamp colony that may impair their survival. Our results can be used as a baseline to achieve management regulations. 相似文献
14.
Azibar Rodríguez-Iruretagoiena Ranju Chowdhury Ainara Gredilla Silvia Fdez-Ortiz deVallejuelo Alberto de Diego Santosh Kumar Sarkar Gorka Arana Juan Manuel Madariaga Perumal Venkatachalam 《Bulletin of environmental contamination and toxicology》2016,97(5):721-727
Absorption, accumulation and translocation of 12 trace elements in nine dominant mangrove plants in the Indian Sundarban Wetland revealed both organ-specific and site-specific characteristics. An overall enrichment of elements was recorded in rhizosediment, exceeding the prescribed effects range-low (ER-L) of consensus based sediment quality guidelines (SQGs) for Cu and Pb. Avicennia officinalis, A. alba, Ceriops decandra and Excoecaria agallocha exhibited unique potential for accumulating Al, Cd, Co, Cr, Cu, Ni, Mn and Zn and could be considered efficient accumulators. Maximum element accumulation in trunk bark (As 6.16, Cr 49.9, Co 2.67, Cu 91.00 and Zn 85.5 mg kg?1) and root/pneumatophore (Al 1000 and Fe 2430 mg kg?1) was recorded. Maximum bioconcentration factor (6.23) in A. officinalis and translocation factor (17.5 for Mn) in C. decandra distinguished their phytoremediation capacity. These halophytes could be used for trace element phytoremediation in stressed sites of Sundarban. 相似文献
15.
Watanabe I Kunito T Tanabe S Amano M Koyama Y Miyazaki N Petrov EA Tatsukawa R 《Archives of environmental contamination and toxicology》2002,43(1):109-120
Concentrations of heavy metals (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Co, and Hg) were determined in the muscle, liver, and kidney of
42 Caspian seals and fishes collected from the Caspian Sea in 1993. Higher Mn and lower Fe and Cu concentrations were found
in the liver in comparison with other marine pinnipeds. Lower Cu concentrations in the liver appear to be a common feature
in small seals belonging to subgenus Pusa, which include ringed, Baikal, and Caspian seals. However, low Fe and high Mn in livers were specific to Caspian seal. Concentrations
of toxic metals such as Hg and Cd were relatively low. Pinniped species can be divided into two groups, based on accumulations
of Cd or Hg in the liver. Interestingly, it was found that Cd-accumulating groups feed on invertebrates, whereas the preferred
diet of Hg accumulators is fish. Caspian seals seemed to belong to the Hg-accumulating group.
Cd and Hg concentrations in the liver and kidney of young animals increased with age. Mercury concentrations in adult animals
increased with age continuously, whereas Cd concentrations in adult animals decreased. This trend might be due to preferential
feeding habits and shift in ratio of Hg and Cd in the diet (i.e., invertebrates to fish).
Received: 10 July 2001/Accepted: 7 January 2002 相似文献
16.
Mora MA 《Archives of environmental contamination and toxicology》2008,55(3):488-495
Although concentrations of organochlorine compounds (OCs) in birds from most of the United States and Canada have decreased
over the last 30 years, there is still concern that migrant birds might be exposed to elevated concentrations of OCs during
migration in Latin America. The Lerma-Chapala Basin in west-central Mexico is an important migration corridor and wintering
area for many species. The objectives of this study were to assess if resident and migrant birds wintering in western Michoacán,
Mexico accumulated elevated concentrations of OCs during fall and spring and to determine if the stable isotopes δ15N, δ13C, and δD could be used to predict burdens and origins of DDE accumulation. Resident and migrant passerine insectivorous birds
were collected during fall and spring (2001–2002) in northwest Michoacán, near Chapala Lake, Mexico. The carcasses were analyzed
for OCs and tail feathers were analyzed for stable isotopes δ15N, δ13C, and δD. The OCs detected in more than 50% of the samples were: oxychlordane (79%), p,p’-DDE (100%), p,p′-DDT (57%), and total PCBs (100%). p,p′-DDE was the OC detected at the highest concentrations, whereas residues of other OCs were near or below detection limits.
Overall, there were no significant differences in concentrations of OCs between seasons or between resident and migrant birds.
Concentrations of DDE and oxychlordane were somewhat higher in migrant and resident birds during spring than in fall; however,
concentrations were significantly different only for oxychlordane. Two resident birds collected in fall and spring had DDE
residues >10 μg/g wet weight in carcass. There were no significant differences in δ13C and δ15N values among species, between seasons, or between migrant and resident birds. However, δD values were clearly different
between species and helped differentiate migrant from resident birds. δD values also were negatively and significantly correlated
with DDE concentrations in carcass. Birds with more depleted δD values in feathers tended to have higher DDE concentrations
than those with less depleted δD values, suggesting a potential latitudinal accumulation of DDE. Overall, our results suggest
that during fall and spring, there is not a significant buildup of persistent OCs in migrant and resident passerine insectivorous
birds in northwest Michoacán, Mexico. 相似文献
17.
Yureidy Cabrera Páez Consuelo Aguilar Betancourt Gaspar González-Sansón Karen A. Kidd Kelly R. Munkittrick R. Allen Curry 《Archives of environmental contamination and toxicology》2012,63(4):523-533
The Almendares River is the largest river draining the area around Havana City, Cuba. The watershed is heavily populated and industrialized, which has had a significant impact on the flow and water quality of the river. The main goal of this study was to analyze the spatial variability in dietary habits, nutrient flow (using stable isotope ratios δ15N and δ13C), and mercury (Hg) levels along the Almendares River upstream and downstream of point-source discharges using localized fish Gambusia puncticulata. Stomach contents of G. puncticulata were similar among these sites. However, mean δ15N values ranged from 6 to 18 ‰ across sites and were lower in fish from downstream than upstream sites, suggesting localized influences of nutrient inputs along the river. δ13C values were between –22 and –25 ‰, except at a mid-basin site (–26 to –27‰), indicating that fish relied on similar carbon sources at most sites. Total mercury concentrations ranged from 0.04 to 0.49?μg/g wet weight whole body and were unrelated to the among-site differences in δ15N, but Hg exceeded the threshold considered to be protective of fish health (0.2?μg/g ww whole body) in the majority of fish from all sites but one. Results of this study indicate that although the dietary habits of this species do not vary across sites, tissue differences in δ15N, δ13C and Hg show little movement of this species among sites. Localized effects of human activities on nutrients and metals may be affecting the health of this species and posing a risk to other consumers in the ecosystem. 相似文献
18.
Aastha Pandey Chhatra Mani Sharma Shichang Kang Qianggong Zhang Lekhendra Tripathee Junming Guo Xiaofei Li Shiwei Sun Rukumesh Paudyal Prakash Acharya Mika Sillanpää 《Bulletin of environmental contamination and toxicology》2017,99(4):500-505
This study quantified concentrations of mercury (Hg) and its trophic transfer along the fish community in the Indrawati River, Nepal. Stable isotope ratios of nitrogen (δ15N) and carbon (δ13C), complemented by stomach contents data were used to assess the food web structure and trophic transfer of Hg in 54 fishes; 43 Shizothorax richardsonii and 11 Barilius spp. [B. bendelisis (1), B. vagra (3) and B. barila (7)]. Sixty-one muscle samples (including six replicates) were used for the analysis of total mercury (THg) and stable isotopes. Mean THg concentrations in B. spp. and the more common species S. richardsonii was observed to be 218.23 (ng/g, ww) and 90.82 (ng/g, ww), respectively. THg versus total length in both S. richardsonii and B. spp. showed a decreasing tendency with an increase in age. Regression of logTHg versus δ15N among the fish species showed a significant positive correlation only in S. richardsonii indicating biomagnification along the trophic level in this species. 相似文献
19.
E. Głowacka P. Migula S.-L. Nuorteva P. Nuorteva E. Tulisalo 《Archives of environmental contamination and toxicology》1997,32(4):376-382
Contents of Al, Fe, Zn, Cu, Cd, Mn, Ni, and Hg were determined in 14 species of psyllids and in leaves of their host plants
from unpolluted sites (Finland) and industrially polluted sites in Poland. Generally, psyllids accumulated low amounts of
metals, but their metal burdens increased with age. Exuvia were important for the elimination of Al, Ni, and Mn, and larval
wax for Al, Cu, and Ni. Biomagnification of metals, expressed as the concentration factor (cf) was low (cf: 0.56–1.08) for
Mn, Al, and Ni, but high for Cd (cf: 5.86). Trioza chenopodii, Cacopsylla ulmi, and Psylla betulae represented the microconcentrators (cf: 0.9–1.25); the remaining species were the macroconcentrators (cf: 2.0–4.9). In polluted
areas Psyllopsis fraxini eliminated large amounts of Al, Fe, Cu, Mn, and Cd with honeydew. This way of metal elimination was of less importance in
species from unpolluted sites. Adults of Cacopsylla mali, P. fraxini, P. betulae, and Cacopsylla sorbi fall a prey to ants and may be important in transfer of Zn, Fe, Cu, Cd, and Ni. In comparison with aphids their role in metal
transfer is marginal, due to better self-defence mechanisms and higher mobility, which protect them from potential predators
and parasites.
Received: 15 March 1996/Revised: 31 August 1996 相似文献
20.
Michael C. Newman Xiaoyu Xu Charles F. Cotton Kyle R. Tom 《Archives of environmental contamination and toxicology》2011,60(4):618-625
The relative contributions of proximity to mercury sources and trophic ecology to realized axial muscle mercury concentrations
were explored for three deep-water chondrichthyans (Etmopterus princeps, Centroscymnus coelolepis, and Hydrolagus affinis), two species of which are harvested for human consumption. Samples were taken at three North Atlantic Ocean locations: the
Azores, the Charlie Gibbs Fracture Zone, and the Bear Seamount. Despite the long distances between anthropogenic sources and
the sampling locations, all species from all locations had muscle mercury concentrations exceeding the United States human
health screening value of 0.3 mg/kg wet weight. Proximity to anthropogenic sources was not an obvious determinant of these
elevated concentrations. Generally, mercury concentrations appeared to increase with increased dependence on benthic versus
pelagic food sources (as indicated by interspecies differences in δ13C), and with higher position in the trophic web (as indicated by differences in δ15N). 相似文献