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1.
Castello M 《Environmental monitoring and assessment》2007,133(1-3):267-276
Transplants of the mosses Hypnum cupressiforme and Pseudoscleropodium purum used as active biomonitors of airborne trace elements were compared in a survey carried out at Trieste (NE Italy). Twelve
elements were considered: Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, Ti, V, Zn. Water-washed materials of H. cupressiforme and P. purum, collected in a remote area to prepare transplants, showed comparable content of all elements, excluding Pb. Transplants
of P. purum showed a significantly higher accumulation of Al, Fe, Pb and Ti; higher levels of Cu and V were accumulated in H. cupressiforme. Losses of some elements occurred in some samples of both species; the most consistent losses regarded Cr and Mn. Accumulation
data of Al, As, Cd, Hg, Zn found in the two transplanted sets were not correlated. Differences in element uptake in the two
mosses are likely to depend mainly on morphology, and probably on the different forms of emission and deposition types of
the elements. The two mosses showed an overall accordance in discriminating sites highly and scarcely affected by trace element
depositions, although they accumulated some elements, in particular Hg and Zn, in different ways. P. purum proved to be a better accumulator than H. cupressiforme, showing similar or higher accumulation and lower loss of almost all elements, especially those related to particulate, dry
depositions; H. cupressiforme could be effective in detecting large-scale patterns, related to wet depositions. These results indicate that these mosses
cannot be used interchangeably for monitoring particular elements, and are able to provide complementary information on different,
local and long-range deposition patterns. 相似文献
2.
Madejón P Murillo JM Marañón T Cabrera F 《Environmental monitoring and assessment》2006,114(1-3):169-189
In this paper, we surveyed the concentration of nine trace elements (As, Cd, Cu, Fe, Mn, Ni, Pb, Tl and Zn) in bermudagrass (Cynodon dactylon) 3 years after the mine spill in Aznalcóllar (south Spain). The results were compared with those that had been obtained for the same species in a previous study, 18 months after the accident. Three types of soil condition were determined: i) unaffected soils (UN, control); ii) cleaned up and amended soils (A, amended); and (iii) non-amended soils, inaccessible to the clean-up and remediation operations (NA, non-amended). The trace element concentrations in the plants were lower than those reported in the first sampling for both washed (plant tissues) and unwashed plants (as consumed by herbivores). Apart from Cd, trace elements concentrations (plant tissues) were similar in the A and the UN soils. In the NA soils, the Cd, Fe, Mn, Zn and Pb levels in unwashed plants were excessive for animal consumption. This wild grass seems to be suitable as a soil stabilizer for spill affected soils and as a biomonitor for soil pollution by some trace elements (As, Cu and Zn); however, its potential for phytoextraction is negligible. 相似文献
3.
Trace element contamination in industrial regions of Poland studied by moss monitoring 总被引:2,自引:0,他引:2
Grodzińska K Frontasyeva M Szarek-Lukaszewska G Klich M Kucharska-Fabiś A Gundorina SF Ostrovnaya TM 《Environmental monitoring and assessment》2003,87(3):255-270
The use of terrestrial mosses as biomonitors in large-scalemulti-element studies of heavy metal deposition from theatmosphere is a well established technique in Europe. Insuch studies it is advantageous to determine as many elements as possible in order to distinguish betweendifferent source categories. A combination of INAA and AAShas been found very useful in this respect, in particularwhen epithermal activation is used for instrumental neutronactivation analysis. A total of 33 elements (Al, Cl, Sc, V,Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Ag, Cd, Sb,I, Cs, Ba, La, Ce, Tb, Yb, Hf, Ta, W, Au, Pb, Th, and U) inPleurozium schreberi (Brid.) Mitt. moss samples fromthe Silesia-Kraków Industrial Region and Legnica-GogówCopper Basin and from the control (background) area inNortheast Poland were identified. The highest concentrationsof the majority of trace elements were found in mossesgrowing in the Silesia-Kraków Industrial Region, only Cu andAs concentrations were higher in mosses in the Legnica-Gogów Copper Basin. These results are in conformity withthe load of trace elements emissions in these areas. 相似文献
4.
A survey is given of the possibilities and restrictions of (bio)monitoring trace metals in the salt marsh as exemplified for the Scheldt estuary. The objectives for monitoring in the salt marsh are enumerated as well as the requirements they should meet. Previous studies on monitoring trace metals in the salt marsh are reviewed.Problems in monitoring trace metals in the soil subsystem are due to variations in the input of these metals, the type of esturine circulation and the distribution of physical and chemical conditions in the salt-marsh deposits. The degree of metal enrichment and the spectrum of chemical speciation of the metals by means of a sequential extraction procedure is shortly discussed.Problems in monitoring trace metals in salt-marsh plants are discussed with respect to the bioavailability of these metals from soil and inundation water as sources of contamination, the allocation and seasonal variation in metal accumulations, and the role of adhesive particulate matter carried on the shoots by the floods. Aster tripolium seems to be a good species for biomonitoring trace metals in the vegetational component of the salt-marsh ecosystem.Communication Nr. 346. 相似文献
5.
Trace Element Concentrations and Bioindicator Responses in Tree Swallows from Northwestern Minnesota 总被引:5,自引:0,他引:5
Custer CM Custer TW Warburton D Hoffman DJ Bickham JW Matson CW 《Environmental monitoring and assessment》2006,118(1-3):247-266
Extremely high concentrations of cadmium (3.5 μg/g dry wgt.) and elevated concentrations of chromium (>10 μg/g dry wgt.) and mercury (1.6 μg/g dry wgt.) were reported in waterbird tissues at Agassiz National Wildlife Refuge in northwestern Minnesota in 1994. Tree
swallows (Tachycineta bicolor) were studied during 1998–2001 at three drainages into the Refuge, two pools on the Refuge, and at a nearby reference location
to document whether high levels of contaminants were still present, and if so to quantify the source and severity of the contamination.
Trace elements were measured in tree swallow eggs, livers, and diet. Reproductive success and bioindicator responses were
monitored. In 2000, water was drawn down on Agassiz Pool, one of the main pools on the Refuge. This presented an opportunity
to evaluate the response of trace element concentrations in the diet and tissues of tree swallows after reflooding. High concentrations
of trace elements were not detected in swallow tissues, nor were there differences among locations. Less than 20% of swallow
samples had detectable concentrations of cadmium or chromium. Mercury concentrations were low and averaged <0.25 μg/g dry wgt. in swallow tissues. Trace elements, including mercury, did not increase in tree swallows following the 2000 drawdown
at Agassiz Pool. Hatching success and survival of nestlings to 12 days-of-age for tree swallows on the Refuge were similar
to the national average and consistent with background trace element concentrations. Bioindicator measurements were within
the normal ranges as well. 相似文献
6.
This is the first comprehensive study of sources of variation in metal concentrations within the whole tissues of a shallow burrowing, filter-feeding intertidal clam, Austrovenus stutchburyi. Samples were collected from 12 sites in April, August, November and February in 1993–1994 in the vicinity of Otago Harbour and Peninsula, New Zealand. Total tissue trace metal concentrations (μg g−1 dry weight) were measured in individual animals for the essential metals : Mn, Cu, Zn, Ni and the non-essential Cr using trace-metal clean acid-digestion and ICP-OAES techniques. Average metal concentrations were 3–60 μg g−1 for Cu, 40–118 μg g−1 for Zn, 2–12 μg g−1 for Mn, 5–35 μg g−1 for Ni and 1–44 μg g−1 for Cr. These levels decreased with body weight and differed amongst sites except for Cr in February (mid-summer). Highest concentrations occurred at sites close to a city (Dunedin) and within the central harbour region although the Cu, Zn, Ni and Cr concentrations did not correlate with the environmental gradient or season. At one coastal site, samples of both the blue mussel Mytilus galloprovincialis and cockles gave similar trends in trace metal levels. These results suggest that the cockle could be a useful trace metal biomonitor within NZ estuaries. 相似文献
7.
Contribution to biomonitoring of some trace metals by deciduous tree leaves in urban areas 总被引:1,自引:0,他引:1
Tomasević M Vukmirović Z Rajsić S Tasić M Stevanović B 《Environmental monitoring and assessment》2008,137(1-3):393-401
Leaves of the deciduous tree species, horse chestnut (Aesculus hippocastanum L.) and Turkish hazel (Corylus colurna L.) were used as accumulative biomonitors of trace metal pollution in the urban area of Belgrade. Using differential pulse
anodic stripping voltametry, trace metal concentrations (Pb, Cu, Zn, Cd) were determined at the single leaf level (ten leaves
per species, per month), during two successive years with markedly different atmospheric level of trace metals. Increased
trace metal concentrations in the leaves of A. hippocastanum reflected elevated atmospheric trace metal pollution, whereas C. colurna L. did not respond accordingly. The contents of Pb and Zn in soil over the same period also followed this trend. Anatomical
analyses, in young as well as in old leaves of both species, indicated typical foliar injuries of plants exposed to stressful
air conditions. Water relations that correspond to leaf age may have contributed to the considerable trace metal accumulation
in leaves. 相似文献
8.
Clifford A. Hui John Y. Takekawa Sarah E. Warnock 《Environmental monitoring and assessment》2001,71(2):107-121
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05). 相似文献
9.
Balachandran KK Jayalakshmy KV Laluraj CM Nair M Joseph T Sheeba P 《Environmental monitoring and assessment》2008,139(1-3):217-226
The interaction effects of abiotic processes in the production of phytoplankton in a coastal marine region off Cochin are
evaluated using multiple regression models. The study shows that chlorophyll production is not limited by nutrients, but their
physiological regulations (responses to nutrients, pH, temperature and salinity) are mainly responsible for the increased
biological production. The model explaining 77% of variability for chlorophyll a production is indicative of preconditioning of the coastal waters. The phytoplankton production is found to be sensitive
to the environment, which varies seasonally. Further, the study suggests that supply of organic matter and grazing of zooplankton
(not included) would improve the model efficiency. Despite this, the good agreement in the computed and measured chlorophyll
a values shows that step-up multiple regression model is a useful tool to understand the influence of environmental variables
on the production of phytoplankton in these coastal waters. 相似文献
10.
Two cage designs and fingernail clams(Sphaerium fabale) were evaluated for theirsuitability for use in in situ bioassays toassess the ecological condition of a stream andpredict ecological recovery potential. One design(referred to as tray design) was a modified plastictray about one-fourth full of small gravels andcovered with 1 mm fiberglass mesh. The second design(referred to as tube-plates) consisted of shortplexiglass tubes about one-third full of small gravelsand attached horizontally to a plexiglass plate. Oneend of each tube faced into the current; both endswere covered with mesh. Cages containing clams weredeployed at reference and impacted (test) sites forperiods of 70 to 135 d. Growth and survival were theprimary endpoints evaluated, but the tube-platesallowed isolation of individual clams so that natalityalso could be evaluated as an endpoint. Results ofbenthic macroinvertebrate surveys, performed foranother study, were included to help validate bioassayresults. Both cage designs yielded good quantitative,site-specific results for clam survival and growth;results for natality, though, were less conclusive. Clam survival and growth results were in good generalagreement with the results for the benthicmacroinvertebrate community surveys. At a site wherethe macroinvertebrate community was the mostdepauperate, clam mortality was always rapid. At asite where the condition of the macroinvertebratecommunity was only slightly less impacted than themost impacted site, clam growth was almost alwayssignificantly lower than at reference sites. Survivalof clams was significantly reduced in <25 d at thissite in some trials, but in other trials there waslittle mortality. At a minimally impacted site, clamsurvival was similar to that found at reference sites,and differences in clam growth were not detectableuntil after 40 to 50 d of exposure. The tube-platedesign was easier to use, allowed more flexibility inselection of response parameters, and required lesshandling time of test animals, thus, this was thepreferred design. Our results demonstrated thateither in situ bioassay design can be used toaugment monitoring and assessment programs. Their useas a predictor of ecological recovery, however,requires further evaluation. 相似文献
11.
Rashed MN 《Environmental monitoring and assessment》2001,68(1):75-89
Cadmium and lead were determined in different tissues (muscle,gill, stomach, intestine, liver, vertebral column and scales) of Tilapia nilotica from the High Dam Lake, Aswan (Egypt) to assess the lake water pollution with those toxic metals. Fish samples were chosen from different ages and weights to be analyzed along with samples of the aquatic plant(Najas armeta), sediment and lake water.The results showed that cadmium and lead concentrations were higher in fish scales and vertebral column than in the other parts of the fish. Cadmium and lead levels in High Dam lake water and fish (Tilapia nilotica) were a result of the pollution which uptakes from aquatic plants, sediments andgasoline containing lead that leaks from fishery boats. Tilapia nilotica fish was used as a good bio-assay indicator for the lake pollution with cadmium and lead. The fish musclesin this study were in the safety baseline levels for man consumption. 相似文献
12.
Trace elements used in animal feed additives can be introduced to aquatic environments through application of manures from
animal feeding operations to agricultural land as fertilizer. The use of poultry feed additives containing arsenic (As) is
of particular concern in the Shenandoah River watershed (Virginia, USA), an agricultural landscape with a high density of
poultry operations. This study investigated the relationship between watershed characteristics of Shenandoah River tributaries
and trace element concentrations in streambed sediment and tissue of resident mollusks, including: Asian clams (Corbicula fluminea), which are commonly used biomonitors, and pleurocerid snails (Leptoxis carinata), which are generally understudied. Results failed to support the primary hypothesis of a predictive relationship between
watershed densities of poultry operations and As concentrations in sediment and mollusk tissue. However, there were statistical
relationships between land use in tributary watersheds and other trace elements in sediment (Cu, Mn, Pb, Zn) and tissue (Cd,
Hg, Pb). Principal components analysis of the sediment data suggested a possible geologic source of As at some sites. Tissue
concentrations of As were significantly higher in snails than in clams, but clams accumulated higher concentrations of other
trace elements (Cd, Cr, Hg, Pb, Se). Snails may be useful biomonitors of environmental As, but appear to be less suitable
than clams for studies of landscape sources of other trace elements. 相似文献
13.
Conti ME Iacobucci M Cecchetti G Alimonti A 《Environmental monitoring and assessment》2008,141(1-3):27-34
Fifty seven samples of Mytilus galloprovincialis (Lamarck, 1819) collected along the breakwater barriers of Fano (station 1) and Pesaro (station 2), Adriatic Sea, Marche
Region, central Italy, were analyzed by atomic absorption spectrometry and Cd, Cu, Pb and Zn concentrations in the soft tissues
were measured. The aims of this work were the statistical analysis of Cd-weight, Cu-weight, Pb-weight, Zn-weight relationships,
and the building of a tendency function that allows assessing with a good approximation the concentrations of a metal in different
weight organisms. In Mytilus galloprovincialis the content of Cd proportionally grew with the weight and therefore its concentration was independent from this factor; while
the concentration of Pb decreased as the weight increased. In both cases the accuracy of multiple regression models improved
considering the variable ‘site’, while the same approach appeared not reliable for Cu and Zn, that were two essential metals.
Our results showed that a tendency function was reliable, solid and able to predict to a very satisfying extent the concentration
of non-physiological metals, like Cd and Pb; while it did not show a good approximation with real Cu and Zn contents. 相似文献
14.
This paper reports the utilization of 4-(2-pyridylazo) resorcinol (PAR) as a chelating reagent for in-column derivatization
and the determination of trace Co, Fe, and Ni ions by reversed-phase high-performance liquid chromatography with photodiode
array detector. A good separation of Co, Fe, and Ni chelates were achieved by using an Inertsil ODS-3 column and a mobile
phase, consisted of methanol–THF–water mixture (50:5:45) containing ammonium acetate buffer (pH 5.0) and PAR. After full optimization,
good repeatability of retention times (relative standard deviation (RSD) < 0.05%) and peak areas (RSD < 1.7%) was achieved
as well as a good linearity (r
2 > 0.9991). The detection limits (S/N = 3), expressed as micrograms per liter, were 0.50 (Co), 9.07 (Fe), and 2.00 (Ni). The applicability and the accuracy of
the developed method were estimated by the analysis of spiked water samples and certified reference material BCR 715 wastewater-SRM. 相似文献
15.
Nagler P Glenn EP Hursh K Curtis C Huete A 《Environmental monitoring and assessment》2005,109(1-3):255-274
A vegetation mapping system for change detection was tested at the Havasu National Wildlife Refuge (HNWR) on the Lower Colorado
River. A low-cost, aerial photomosaic of the 4200 ha, study area was constructed utilizing an automated digital camera system,
supplemented with oblique photographs to aid in determining species composition and plant heights. Ground-truth plots showed
high accuracy in distinguishing native cottonwood (Populus fremontii) and willow (Salix gooddingii) trees from other vegetation on aerial photos. Marsh vegetation (mainly cattails, Typha domengensis) was also easily identified. However, shrubby terrestrial vegetation, consisting of saltcedar (Tamarix ramosissima), arrowweed (Pluchea sericea), and mesquite trees (Prosopis spp.), could not be accurately distinguished from each other and were combined into a single shrub layer on the final vegetation
map. The final map took the form of a base, shrub and marsh layer, which was displayed as a Normalized Difference Vegetation
Index map from a Landsat Enhanced Thematic Mapper (ETM+) image to show vegetation intensity. Native willow and cottonwood
trees were digitized manually on the photomosaic and overlain on the shrub layer in a GIS. By contrast to present, qualitative
mapping systems used on the Lower Colorado River, this mapping system provides quantitative information that can be used for
accurate change detection. However, better methods to distinguish between saltcedar, mesquite, and arrowweed are needed to
map the shrub layer. 相似文献
16.
Hsu BM Wu NM Jang HD Shih FC Wan MT Kung CM 《Environmental monitoring and assessment》2005,104(1-3):155-162
The flow cytometry (FC) has been used to detect Giardia cysts and Cryptosporidium oocysts quantitatively and instantaneously in this study. The experimental results showed that FC is potential to become a more precise method for the detection of Giardia and Cryptosporidium in water. This study also evaluated the staining efficiencies for three commercial antibodies. After staining Cryptosporidium oocysts with direct immunofluorescent antibodies in water samples, two populations were detected in the scatter-plots (FL1 versus SSC) of the FC. The Cryptosporidium oocysts and Giardia cysts are significantly separated from other particles while stained with direct immunofluorescent antibodies produced by Meridian Diagnostics and WaterborneTM Inc. 相似文献
17.
Microbial risk was quantified to assess human health risk as a result of exposure to E. coli in reclaimed wastewater irrigation. Monitoring data on E. coli were collected from pond water in paddy rice plots during the growing season. Five treatments were used and each was triplicated
to evaluate the changes in E. coli concentrations in experiments performed in 2003 and 2004. The Beta-Poisson model was used to estimate the microbial risk
of pathogen ingestion among farmers and neighboring children. A Monte Carlo simulation (10,000 trials) was conducted to estimate
the risk associated with uncertainty. In this study, risk values ranged from 10−4 to 10−8. UV-disinfected irrigation water showed a lower risk value than others, and its level was within the range of the actual
paddy rice field with surface water. Agricultural activity was thought to be safer after 1–2 days, when the paddy field was
irrigated with reclaimed wastewater. Also, children were found to have a greater risk of infection with E. coli. This paper should be viewed as a first step in the application of quantitative microbial risk assessment of wastewater reuse
in paddy rice culture. 相似文献
18.
Introduction of the Factor of Partitioning in the Lithogenic Enrichment Factors of Trace Element Bioaccumulation in Plant Tissues 总被引:1,自引:0,他引:1
Bioindicators are widely used in the study of trace elements inputs into the environment and great efforts have been conducted to separate atmospheric from soil borne inputs on biomass accumulation. Many monitoring studies of trace element pollution take into account the dust particles located in the plant surface plus the contents of the plant tissues. However, it is usually only the trace element content in the plant tissues that is relevant on plant health. Enrichment factor equations take into account the trace element enrichment of biomasses with respect soil or bedrocks by comparing the ratios of the trace element in question to a lithogenic element, usually Al. However, the enrichment equations currently in use are inadequate because they do not take into account the fact that Al (or whichever reference element) and the element in question may have different solubility-absorption-retention levels depending on the rock and soil types involved. This constrain will become critical when results from different sites are compared and so in this article we propose that the solubility factors of each element are taken into account in order to overcome this constrain. We analysed Sb, Co, Ni, Cr, Pb, Cd, Mn, V, Zn, Cu, As, Hg, and Al concentration in different zones of Catalonia (NE Spain) using the evergreen oak Quercus ilex and the moss Hypnum cupressiforme as target species. We compared the results obtained in rural and non industrial areas with those from the Barcelona Metropolitan Area. We observed differences in Al concentrations of soils and bedrocks at each different site, together with the differences in solubility between Al and the element in question, and a weak correlation between total soil content and water extract content through different sites for most trace elements. All these findings show the unsuitability of the current enrichment factors for calculating lithospheric and atmospheric contributions to trace element concentrations in biomass tissues. The trace element enrichment factors were calculated by subtracting the part predicted by substrate composition (deduced from water extracts from soils and bedrock) from total concentrations. Results showed that for most of the trace elements analysed, trace elements enrichment factors were higher inside the Barcelona Metropolitan Area than outside, a finding that indicates that greater atmospheric inputs occur in urban areas. The results show that the most useful and correct way of establishing a reference for lithospheric and atmospheric inputs into the plant tissues is, first, to analyse samples of the same plant species collected from a number of sites possessing similar environmental conditions (climate, vegetation type, soil type) and, second, to use this new enrichment factor obtained by subtracting from the total concentration in plant tissue the predicted contribution of soil or bedrock extracts instead of that of total soil or bedrock concentrations. 相似文献
19.
Delta-aminolevulinate dehydratase (ALAD) activity has been used in prokaryotes and eukaryotes as a biomarker for environmental
lead (Pb) exposure and toxicity. Microorganisms are sensitive indicators of toxicity at the fundamental level of ecological
organization, but bacterial biomarker studies are focused on the Pseudomonas strains in Group I and E coli. The objectives of the present work were to determine if Burkholderia gladioli belonging to group II, due to its 16SrRNA similarity, can be used as biomarker in metal contamination and compare its possible
usage with Pseudomonas aeruginosa and Citrobacter freundii (previously known as Esherichia freundii) and Bacterium freundii which are classified in Group I. In this study, ALAD activity in an environmental strains of Burkholderia gladioli, Pseudomonas aeruginosa, Citrobacter freundii were investigated to evaluate potential inhibition by Pb and other toxic metals. When the ALAD activity of Burkholderia gladioli was tested, Co and Pb decreased activity by 27 and 71%, respectively. In addition to these findings, Zn increased the activity
up to 26%. These effects were found to be statistically meaningful (p < 0.05). It was determined that the increase of lead concentration inhibites the ALAD activity at each of the three strains.
There was a statistically significant dose–response relationship between ALAD activity in cells of Burkholderia gladioli and Pb (Pearson correlation coefficent = −0.665; r
2 = 0.665, and p < 0.001). The strongest ALAD inhibition which was measured was 90% at Burkholderia gladioli when protein extracts were incubated with 750 μM of Pb. The relationship between Pb and ALAD activity was statistically described
by [ALAD Activity] = 0.476−0.000597 × [Pb]. According to the obtained results, we suggest that the ALAD of Burkholderia gladioli can be used as a biomarker for lead contamination in the environment. 相似文献
20.
Zhang Y Ruan L Fasola M Boncompagni E Dong Y Dai N Gandini C Orvini E Ruiz X 《Environmental monitoring and assessment》2006,118(1-3):355-368
The rapidly developing Asian countries may face threatening environmental contamination, that however remains largely unassessed.
We studied persistent trace elements in three wetlands, Poyang Lake, relatively unpolluted, and Tai Lake, and Pearl River
Delta, selected as hotspots of pollution in Central China. We adopted as indicator the Little Egret, a widespread colonial
waterbird, and during 1999 and 2000 we collected and analysed the same samples as for a parallel study we conducted in Pakistan,
e.g. eggs, body feathers of chicks, prey spontaneously regurgitated by the chicks, and sediments at the areas most used by
foraging egrets. The levels of trace-metals at our three study areas were similar, or within the range, of those found in
the few other studies for East Asia, with few exceptions. The concentrations of the various elements were below the threshold
that may affect the survival or reproduction of the birds, and even the highest concentrations relative to background, i.e.
Se in eggs, and Hg in feathers at Pearl Delta, do not pose toxic hazards. In sediments, the levels of trace elements were
lower than the critical levels assumed for contaminated soil, except for alarming high levels of As at Poyang. These results
do not confirm our expectation, that Poyang was relatively uncontaminated, while Tai and Pearl were polluted. Although trace
metal concentration differed significantly among the three study areas, these differences were minor and were not consistent
among elements and samples. The bioaccumulation ratios from sediments through prey, feather and egg, were consistent with
our previous findings for Pakistan. Only Hg exhibited high bioaccumulation, while Se and Zn had low accumulation, and the
other elements no accumulation. This reasserts that feathers of predators such as egrets, may be more sensitive indicators
of environmental contamination for the elements subject to bioaccumulation, whereas the sediments or the organisms low in
the food chain are better indicators for the other elements. 相似文献