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1.
The technique of diffusion gradient in thin films (DGT) for assessing bioavailable metals has not been tested under field
conditions. We assessed the relationships of DGT- and cation exchange resin-membrane-measured concentrations of Cd, Cu, Pb,
and Zn with plant uptake of the metals under greenhouse and field conditions. In the greenhouse, the effective concentrations
of Cu, Pb, and Zn by DGT correlated significantly with uptake by sorghum (Sorghum bicolor), but cation exchange resin-membrane-measured concentrations of Cd, Pb, and Zn did not correlate with sorghum uptake. In
the field, the DGT-measured concentrations of Cd, Pb, and Zn were not linearly related to uptake Cd, Pb, and Zn by lettuce
(Lactuca sativa) except for Cu uptake (r = 0.87, p < 0.05). Similarly, it was only the resin-membrane-extractable Pb that correlated with Pb uptake by lettuce (r = 0.77; p < 0.05). However, fitting non-linear regression models improved the plant metal uptake predictions by DGT-measured bioavailable
Cd, Cu, Pb, and Zn under field conditions. In conclusion, the DGT technique was fairly predictive of bioavailability in the
greenhouse, but not in the field. 相似文献
2.
Health risk assessment of heavy metals for edible parts of vegetables grown in sewage-irrigated soils in suburbs of Baoding City,China 总被引:1,自引:0,他引:1
Zhan-Jun Xue Shu-Qing Liu Yan-Ling Liu Yong-Lu Yan 《Environmental monitoring and assessment》2012,184(6):3503-3513
With the long-term application of wastewater to vegetable production fields, there is concern about potential health risks
of heavy metals contaminating the edible parts of vegetables grown in contaminated soils in the suburban areas of Baoding
City, China. The average concentration of elemental Zn in sewage-irrigated soil was the highest (153.77 mg kg−1), followed by Pb (38.35 mg kg−1), Cu (35.06 mg kg−1), Ni (29.81 mg kg−1), and Cd (0.22 mg kg−1) which were significantly higher (P < 0.05) than those in the reference soil. The results showed that long-term sewage irrigation had led to a growing accumulation
of heavy metals in the soils, especially for Cd, Zn, and Pb. Furthermore, the concentrations of elemental Cd, Zn, and Ni in
vegetables (e.g., Beassica pekinensis L., Allium fistulosum L., Spinacia oleracea L.) collected from the wastewater-irrigated soils exceeded the maximum permissible limits, and this also increased the daily
intake of metals by food. However, compared with the health risk index of <1 for heavy metals, the ingestion of vegetables
from the soils irrigated with sewage effluent posed a low health risk. Nevertheless, heavy metal concentrations should be
periodically monitored in vegetables grown in these soils together with the implementation effective remediation technologies
to minimize possible impacts on human health. 相似文献
3.
A field study was conducted in the fly ash lagoons of Santandih Thermal Power Plant located in West Bengal (India) to find
out total, EDTA and DTPA extractable metals in fly ash and their bioaccumulation in root and shoot portion of the naturally
growing vegetation. Fly ash sample has alkaline pH and low conductivity. The concentration of total Cu, Zn, Pb and Ni were
found higher than weathered fly ash and natural soil, where as Co, Cd and Cr were found traces. Five dominant vegetation namely,
Typha latifolia, Fimbristylis dichotoma, Amaranthus defluxes, Saccharum spontaenum and Cynodon dactylon were collected in the winter months (November–December). Bioaccumulation of metals in root and shoot portions were found
varied significantly among the species, but all concentration were found within toxic limits. Correlation between total, DTPA
and EDTA extractable metals viz. root and shoot metals concentration were studied. Translocation factor (TF) for Cu, Zn and
Ni were found less than unity, indicates that these metals are immobilized in the root part of the plants. Metals like Mn
have TF greater than unity. The study infers that natural vegetation removed Mn by phytoextraction mechanisms (TF > 1), while
other metals like Zn, Cu, Pb and Ni were removed by rhizofiltration mechanisms (TF < 1). The field study revealed that T. latifolia and S. spontaenum plants could be used for bioremediation of fly ash lagoon. 相似文献
4.
Barman SC Singh R Negi MP Bhargava SK 《Environmental monitoring and assessment》2008,137(1-3):495-504
The present study deals with the effect of fireworks on ambient air quality during Diwali Festival in Lucknow City. In this
study, PM10, SO2, NO
x
and 10 trace metals associated with PM10 were estimated at four representative locations, during day and night times for Pre Diwali (day before Diwali) and Diwali
day. On Diwali day 24 h average concentration of PM10, SO2, and NO
x
was found to be 753.3, 139.1, and 107.3 μg m−3, respectively, and these concentrations were found to be higher at 2.49 and 5.67 times for PM10, 1.95 and 6.59 times for SO2 and 1.79 and 2.69 for NO
x
, when compared with the respective concentration of Pre Diwali and normal day, respectively. On Diwali day, 24 h values for
PM10, SO2, and NO
x
were found to be higher than prescribed limit of National Ambient Air Quality Standard (NAAQS), and exceptionally high (7.53
times) for PM10. On Diwali night (12 h) mean level of PM10, SO2 and NO
x
was 1,206.2, 205.4 and 149.0 μg m−3, respectively, which was 4.02, 2.82 and 2.27 times higher than their respective daytime concentrations and showed strong
correlations (p < 0.01) with each other. The 24 h mean concentration of metals associated with PM10 was found to be in the order of Ca (3,169.44) > Fe (747.23) > Zn (542.62) > Cu (454.03), > Pb (307.54) > Mn (83.90) > Co
(78.69) > Cr (42.10) > Ni (41.47) > Cd (34.69) in ng m−3 and all these values were found to be higher than the Pre Diwali (except Fe) and normal day. The metal concentrations on
Diwali day were found to be significantly different than normal day (except Fe & Cu). The concentrations of Co, Ni, Cr and
Cd on Diwali night were found to be significantly higher than daytime concentrations for Pre Diwali (control). The inter correlation
of metals between Ca with Pb, Zn with Ni and Cr, Cu with Co, Co with Mn, Ni with Cd, Mn with Cd, Ni with Cd and Cr, and Cr
with Cd showed significant relation either at p < 0.05 or P < 0.01 levels, which indicated that their sources were the same. The metals Cu, Co, Ni, Cr and Cd showed significant (p < 0.01) association with PM10. These results indicate that fireworks during Diwali festival affected the ambient air quality adversely due to emission
and accumulation of PM10, SO2, NO
x
and trace metals.
ITRC Communication Number 2538 相似文献
5.
Pasture selection by livestock is an essential topic for rangeland management, especially in trace element-contaminated soils.
We have studied the composition (nutrients and trace elements) of a grass-based diet from soils affected by a mine spill at
different growth stages (October 2008 to May 2009). A diet based on other plants (mainly Compositae species) was also studied (May 2009) for comparison. Faeces and mane hair of horses feeding on these pastures were also analysed.
Micronutrient (Cu, Fe, Mn and Zn) and potentially toxic trace element (As, Cd, Pb, Tl) concentrations were below the maximum
tolerable levels (MTL) for horses, except for Fe (at early growth of pastures) and Cd (in the diet based on ‘other’ plants).
Values of potential ingestion of Fe by horses were higher than 10 mg kg body weight − 1 day − 1. Cadmium concentrations in some pasture samples (those composed of Compositae species) were higher than 3 mg kg − 1. Potential toxicity of such Cd levels in pastures is uncertain, since a high disparity of criteria about MTL by cattle exists
(between 0.5 and 10 mg kg − 1 diet). Nutrient concentrations were adequate for horses, which could counteract possible harmful effects derived from trace
element ingestion. The analyses of excreta and mane hair point to the low risk of toxicity derived from the consumption of
these contaminated pastures. However, the ingestion of regenerating pastures (autumnal samples) should be avoided due to the
greater risk of ingestion of contaminated soil attached to the plant material. Management of these pastures by grazing requires
periodic monitoring. Special attention should be given to Fe and particularly Cd (non-essential element) which accumulates
in animal organs, where it could provoke uncertain long-term effects. 相似文献
6.
Statistical source identification of metals in groundwater exposed to industrial contamination 总被引:1,自引:0,他引:1
Tariq SR Shah MH Shaheen N Jaffar M Khalique A 《Environmental monitoring and assessment》2008,138(1-3):159-165
Levels of selected metals Na, Ca, Mg, K, Fe, Mn, Cr, Co, Ni, Cd, Pb and Mn were estimated by flame atomic absorption spectrophotometry
in groundwater samples from Kasur, a significant industrial city of Pakistan. Salient mean concentration levels were recorded
for: Na (211 mg/l), Ca (187 mg/l), Mg (122 mg/l), K (87.7 mg/l), Fe (2.57 mg/l) and Cr (2.12 mg/l). Overall, the decreasing
metal concentration order was: Na > Ca > Mg > K > Fe > Cr > Zn > Co > Pb > Mn > Ni > Cd. Significantly positive correlations
were found between Na–Cr (r = 0.553), Na–Mn (r = 0.543), Mg–Fe (r = 0.519), Mg–Cr (r = 0.535), Pb–K (r = 0.506) and Pb–Ni (r = 0.611). Principal Component Analysis and Cluster Analysis identified tannery effluents as the main source of metal contamination
of the groundwater. The present metal data showed that Cr, Pb and Fe levels were several times higher than those recommended
for water quality by WHO, US-EPA, EU and Japan. The elevated levels of Cr, recorded as 21–42 fold higher compared with the
recommended quality values, were believed to originate from the tanning industry of Kasur. 相似文献
7.
Metal release from serpentine soils in Sri Lanka 总被引:2,自引:0,他引:2
Meththika Vithanage Anushka Upamali Rajapaksha Christopher Oze Nishanta Rajakaruna C. B. Dissanayake 《Environmental monitoring and assessment》2014,186(6):3415-3429
Ultramafic rocks and their related soils (i.e., serpentine soils) are non-anthropogenic sources of metal contamination. Elevated concentrations of metals released from these soils into the surrounding areas and groundwater have ecological-, agricultural-, and human health-related consequences. Here we report the geochemistry of four different serpentine soil localities in Sri Lanka by coupling interpretations garnered from physicochemical properties and chemical extractions. Both Ni and Mn demonstrate appreciable release in water from the Ussangoda soils compared to the other three localities, with Ni and Mn metal release increasing with increasing ionic strengths at all sites. Sequential extraction experiments, utilized to identify “elemental pools,” indicate that Mn is mainly associated with oxides/(oxy)hydroxides, whereas Ni and Cr are bound in silicates and spinels. Nickel was the most bioavailable metal compared to Mn and Cr in all four soils, with the highest value observed in the Ussangoda soil at 168?±?6.40 mg kg?1 via the 0.01-M CaCl2 extraction. Although Mn is dominantly bound in oxides/(oxy)hydroxides, Mn is widely dispersed with concentrations reaching as high as 391 mg kg?1 (Yudhaganawa) in the organic fraction and 49 mg kg?1 (Ussangoda) in the exchangeable fraction. Despite Cr being primarily retained in the residual fraction, the second largest pool of Cr was in the organic matter fraction (693 mg kg?1 in the Yudhaganawa soil). Overall, our results support that serpentine soils in Sri Lanka offer a highly labile source of metals to the critical zone. 相似文献
8.
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
9.
Assessment of phenanthrene bioavailability in aged and unaged soils by mild extraction 总被引:2,自引:0,他引:2
Khan MI Cheema SA Shen C Zhang C Tang X Shi J Chen X Park J Chen Y 《Environmental monitoring and assessment》2012,184(1):549-559
It has become apparent that the threat of an organic pollutant in soil is directly related to its bioavailable fraction and
that the use of total contaminant concentrations as a measure of potential contaminant exposure to plants or soil organisms
is inappropriate. In light of this, non-exhaustive extraction techniques are being investigated to assess their appropriateness
in determining bioavailability. To find a suitable and rapid extraction method to predict phenanthrene bioavailability, multiple
extraction techniques (i.e., mild hydroxypropyl-β-cyclodextrin (HPCD) and organic solvents extraction) were investigated in soil spiked to a range of phenanthrene levels (i.e.,
1.12, 8.52, 73, 136, and 335 μg g − 1 dry soil). The bioaccumulation of phenanthrene in earthworm (Eisenia fetida) was used as the reference system for bioavailability. Correlation results for phenanthrene suggested that mild HPCD extraction
was a better method to predict bioavailability of phenanthrene in soil compared with organic solvents extraction. Aged (i.e.,
150 days) and fresh (i.e., 0 day) soil samples were used to evaluate the extraction efficiency and the effect of soil contact
time on the availability of phenanthrene. The percentage of phenanthrene accumulated by earthworms and percent recoveries
by mild extractants changed significantly with aging time. Thus, aging significantly reduced the earthworm uptake and chemical
extractability of phenanthrene. In general, among organic extractants, methanol showed recoveries comparable to those of mild
HPCD for both aged and unaged soil matrices. Hence, this extractant can be suitable after HPCD to evaluate risk of contaminated
soils. 相似文献
10.
Herrero-Hernández E Andrades MS Rodríguez-Cruz MS Arienzo M Sánchez-Martín MJ 《Environmental monitoring and assessment》2012,184(5):3359-3371
The long-term variability of total Cu content from fungicides applied in a certified wine region of Spain (La Rioja) and of
other metals (Cd, Cr, Ni, Pb, and Zn) was evaluated in three young vineyard soils and subsoils unamended and amended with
spent mushroom substrates (SMS) over a 3-year period (2006–2008). SMS is a promising agricultural residue as an amendment
to increase the soil organic matter content but may modify the behaviour of metals from pesticide utilisation in vineyards.
Fresh and composted SMS was applied each year at a rate of 25 t ha−1 (dry-weight). Copper concentrations in the three unamended soils were 21.2–88.5, 25.5–77.1, and 29.4–78.4 mg kg−1. They exceeded natural Cu concentrations of the region and reference sub-lethal hazardous concentration for soil organism.
The concentrations of Cd, Ni, Pb, and Zn were largely below the sub-lethal limits. Thus, although Cu levels were lower than
those of established vineyards, vine performance, and productivity might be affected. The variation in behaviour between different
amendments for each soil was high, so a generic conclusion could not be drawn. The amendment practice seemed to have caused
temporarily Cu mobilization respect to untreated soils. Total zinc concentrations fall within the range of the natural soil
of La Rioja and were significantly affected (p < 0.05) especially by fresh state SMS addition, with increasing up to 75% respect to untreated specimen. The results indicated
a build-up of fresh sites for metal retention at both surface and subsurface level, although no accumulation of metals was
observed in the short-term period. However, the benefit for soils and the negative effects need to be monitored in the long
run. 相似文献
11.
Metal fractionation provides information on mobility and stability of various metal species which can be used to evaluate
the movement of such metals in soils. The effect of wastewater irrigation on the fractions, spatial distribution, and mobility
of cadmium (Cd) and zinc (Zn) was investigated in five urban gardens in Kano, Nigeria. Concentration of total Zn in the surface
soils (0–20 cm) ranged from 121 to 207 mg kg − 1 while Cd concentration was 0.3–2.0 mg kg − 1. Speciation of both heavy metals into seven operationally defined fractions indicated that the most reactive forms extracted
with ammonium nitrate and ammonium acetate, also considered as the bioavailable fractions, accounted for 29–42% of total Cd
and 22–54% of total Zn, respectively. The weakly bound fractions of Cd and Zn reached up to 50% of the total Cd and Zn concentrations
in the soils. Such high proportions of labile Cd and Zn fractions are indicative of anthropogenic origins, arising from the
application of wastewater for irrigation and municipal biosolids for soil fertility improvement. Thus, given the predominance
of sandy soil textures, high concentrations of labile Cd and Zn in these garden soils represent a potential hazard for the
redistribution and translocation of these metals into the food chain and aquifer. 相似文献
12.
Chl. a, Chl. b, total Chl., Carotenoid, Protein and OD 435/OD 415 ratio were measured to estimate the possible damage caused
by the metallic pollutants in the lichen, Pyxine subcinerea Stirton collected from four different sites of Srinagar Garhwal, Uttaranchal, India. Multiple correlation analysis revealed
significant correlation (P < 0.001) among the Fe, Ni, Cu, Cr, Zn and Pb metals analysed. Cd did not correlate with any other metals except Fe (P < 0.05). Cu, Pb and Zn, are the main constituents of the vehicular emissions had significant positive correlation (P < 0.001) with protein content while, the OD 435/OD 415 ratio values decreased statistically (P < 0.001) with increase in amount of Cu, Pb and Zn. 相似文献
13.
Thompson ID 《Environmental monitoring and assessment》2006,116(1-3):263-273
A pilot scale study was conducted to find out the different forms of metals if fly ash (FA) and bioaccumulation of these metals
in the naturally growing vegetation on FA dumps. The total, acid extractable, bioavailable and water soluble fraction of metals
of Fe, Cu, Mn, Zn, Ni, Co and Pb, and their bioaccumulation coefficients (BAC) on naturally growing vegetation were determined.
FA samples had a neutral pH, low electrical conductivity, low organic C and trace amounts of N and P. The relative abundance
of total metals in FA were found in the order Fe ≤ ≤ Zn ≤ Ni ≤ Co ≤ Cu. The concentration of bioavailable (DTPA) metals depend
on the type and nature of coal used in thermal power stations. In the water the extract solution, only Fe and Zn were found
above detection limits. After one year only four species of naturally occurring herbaceous vegetation were found growing and
Cynodon dactylon (grass) covered almost entire surface of the FA. Iron accumulated to the greatest extent in vegetation followed by Mn, Zn,
Cu, Pb, Ni and Co. The sequence of BAC for different metals were Fe (202) ≤ Mn (90) ≤ Zn (63) ≤ Pb (49) ≤ Ni (41) ≤ Cu (24).
The experimental study revealed that Cynodon grass could be used for remediation of fly ash without any amendments, as this grass species act as metal excluder type. 相似文献
14.
Accumulation and tolerance characteristics of cadmium in Chlorophytum comosum: a popular ornamental plant and potential Cd hyperaccumulator 总被引:3,自引:0,他引:3
The effects on the growth, physiological indexes and the cadmium (Cd) accumulation in Chlorophytum comosum under Cd stress were examined by pot-planting. The results showed that the tolerance index (TI) of C. comosum were all above 100 in soil Cd concentration of 100 mg kg − 1. The O2·-_{2^{\bullet}}^{-} production rate and electrical conductivity of C. comosum were significantly positively correlated to Cd adding-concentration while the MDA content increased and had significant differences
with the control. The activities of SOD, CAT, and POD all rose significantly in lower Cd concentration and the Cd threshold
of them were around 10, 50 and 20 mg kg − 1, respectively. The Cd in C. comosum root and aboveground part reached 1,522 and 865·5 mg kg − 1, respectively, in Cd concentration of soil up to 200 mg kg − 1. For the advantages of high tolerance, high accumulation, and high ornamental value, C. comosum may have tremendous application value in the treatment of Cd-contaminated soils. 相似文献
15.
The purpose of this study was to predict quantitative changes in evaporation from bare soils in the Mediterranean climate
region of Turkey in response to the projections of a regional climate model developed in Japan (hereafter RCM). Daily RCM
data for the estimation of reference evapotranspiration (ET
r) and soil evaporation were obtained for the periods of 1994–2003 and 2070–2079. Potential evaporation (E
p) from bare soils was calculated using the Penman–Monteith equation with a surface resistance of zero. Simulation of actual
soil evaporation (E
a) was carried out using Aydin model (Aydin et al., Ecological Modelling 182:91–105, 2005) combined with Aydin and Uygur (2006,
A model for estimating soil water potential of bare fields. In Proceedings of the 18th International Soil Meeting (ISM) on Soils Sustaining Life on Earth, Managing Soil and Technology,
Sanliurfa, 477–480pp.) model of predicting soil water potential at the top surface layer of a bare soil, after performances of Aydin
model (R
2 = 94.0%) and Aydin and Uygur model (R
2 = 97.6) were tested. The latter model is based on the relations among potential soil evaporation, hydraulic diffusivity,
and soil wetness, with some simplified assumptions. Input parameters of the model are simple and easily obtainable such as
climatic parameters used to compute the potential soil evaporation, average diffusivity for the drying soil, and volumetric
water content at field capacity. The combination of Aydin and Aydin and Uygur models appeared to be useful in estimating water
potential of soils and E
a from bare soils, with only a few parameters. Unlike ET
r and E
p projected to increase by 92 and 69 mm (equivalent to 8.0 and 7.3% increases) due to the elevated evaporative demand of the
atmosphere, respectively, E
a from bare soils is projected to reduce by 50 mm (equivalent to a 16.5% decrease) in response to a decrease in rainfall by
46% in the Mediterranean region of Turkey by the 2070s predicted by RCM, and consequently, to decreased soil wetness in the
future. 相似文献
16.
Remeteiová D Rusnák R Kucanová E Fióová B Ružičková S Fekete I Horváth M Dirner V 《Environmental monitoring and assessment》2012,184(2):1121-1130
In this work are presented results of the complex study of two significant solid environmental samples: gravitation dust sediments
(industrial pollutants, potential source of risk elements input to soils) and soils (component of the environment, potential
source of risk elements input to food web). The first phase of this study was focused on the study of the significant chemical
properties (phase composition, content of organic and inorganic carbon) of the dust and soil samples. In the second phase,
the fractionation analysis was used on the evaluation of the mobility of chosen risk elements (Cu, Ni, Pb, Zn) in the studied
samples. The single-step extractions were applied in the order of the isolation of the element forms (fractions), with different
mobilities during defined ecological conditions by utilization of the following reagents: 1 mol dm − 3 NH4NO3 for isolation of the “mobile” fraction, 0.05 mol dm − 3 ethylenediaminetetraacetic acid and 0.43 mol dm − 3 CH3COOH for isolation of the “mobilizable” fraction, and 2 mol dm − 3 HNO3 for isolation of all releasable forms. On the basis of the results obtained in this study, it is possible to state that different
origins and positions of solid environmental samples in the environment reflect in different chemical properties of their
matrix. The different properties of the sample matrix result in different mobilities of risk elements in these kinds of samples.
The fractionation analysis with single-step extraction for isolation element fractions is the method most suitable for easy
checking of environmental pollution and for evaluation of risk elements cycle in the environment. 相似文献
17.
Wigand C McKinney RA Cole ML Thursby GB Cummings J 《Environmental monitoring and assessment》2007,131(1-3):71-81
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this
study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ
15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ
15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ
15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ
15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas,
the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ
15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R
2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ
15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ
15N of Spartina relates with the integrated, watershed-sea nitrogen inputs. 相似文献
18.
Fecal source tracking by antibiotic resistance analysis on a watershed exhibiting low resistance 总被引:2,自引:0,他引:2
The ongoing development of microbial source tracking has made it possible to identify contamination sources with varying accuracy,
depending on the method used. The purpose of this study was to test the efficiency of the antibiotic resistance analysis (ARA)
method under low resistance by tracking the fecal sources at Turkey Creek, Oklahoma exhibiting this condition. The resistance
patterns of 772 water-isolates, tested with nine antibiotics, were analyzed by discriminant analysis (DA) utilizing a five-source
library containing 2250 isolates. The library passed various representativeness tests; however, two of the pulled-sample tests
suggested insufficient sampling. The resubstitution test of the library individual sources showed significant isolate misclassification
with an average rate of correct classification (ARCC) of 58%. These misclassifications were explained by low antibiotic resistance
(Wilcoxon test P < 0.0001). Seasonal DA of stream E. coli isolates for the pooled sources human/livestock/deer indicated that in fall, the human source dominated (P < 0.0001) at a rate of 56%, and that human and livestock respective contributions in winter (35 and 39%), spring (43 and
40%), and summer (37 and 35%) were similar. Deer scored lower (17–28%) than human and livestock at every season. The DA was
revised using results from a misclassification analysis to provide a perspective of the effect caused by low antibiotic resistance
and a more realistic determination of the fecal source rates at Turkey Creek. The revision increased livestock rates by 13–14%
(0.04 ≤ P ≤ 0.06), and decreased human and deer by 6–7%. Negative misclassification into livestock was significant (0.04 ≤ P ≤ 0.06). Low antibiotic resistance showed the greatest effect in this category. 相似文献
19.
Kontas A 《Environmental monitoring and assessment》2012,184(5):2605-2616
The concentrations of trace metals (Cu, Zn, Mn, Ni, and Fe) from suspended particulate matter (SPM) and biota in Izmir Bay
(Eastern Aegean Sea) were studied in order to evaluate the environmental impact of the anthropogenic metals before building
of Wastewater Treatment Plant. SPM samples were collected in wet and dry periods from Izmir Bay. Metal concentrations in SPM
(Cu, 0.36–2.19; Mn, 0.07–11.3; Ni, 0.43–7.81; Zn, 7.33–269; Fe, 1.00–266 μgdm − 3) were comparable to those reported for other moderately polluted bays. Maximum metal concentrations in SPM were observed
during summer season. SPM metal concentrations displayed a clear spatial trend with values increasing with proximity to urban
centers. Cu and Zn concentrations in SPM were especially high in the inner bay. SPM were found to be contaminated by Zn. The
vertical profile of Mn, Zn, and Ni concentrations in SPM had a maximal value at the upper layer and decreased to minimal value
at the bottom layer of the inner bay in summer, in contrast to the observed pattern of Fe and Cu. Maximum Cu concentrations
were obtained in Penaeus kerathurus. Also, maximum Zn and Fe concentrations were found in Mytilus galloprovincialis. Relatively high Cu levels were found in Sardina pilcardus and Mullus barbatus than other fish species. Besides, Cu levels were lower in Diplodus annularis and Merluccius merluccius. Finally, metal levels in biota tissues were lower than the limits of European Dietary Standards and Guidelines. 相似文献
20.
Hosseini Alhashemi A Karbassi A Hassanzadeh Kiabi B Monavari SM Sekhavatjou MS 《Environmental monitoring and assessment》2012,184(4):1865-1878
In the present research, accumulation of Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn were determined in sediments and fillet, liver,
kidney, gonads, and gills of three commonly fish species in the largest wetland ecosystem that is located in southwest of
Iran; Shadegan wetland. Shadegan is one of the most important wetland that posses various fauna and flora but suffers inputs
from agricultural and industrial activities. So, sediment samples and fish species including Barbus grypus, Barbus sharpeyi, and Cyprinus carpio were collected during winter 2009. Results showed that mean concentrations of trace elements (except Ni and Co) were high
in liver and gills of B. grypus. Also trace elements had the most accumulation in liver of B. sharpeyi except for Cd (0.26 mg kg − 1 d.w.) and Mn (13.45 mg kg − 1 d.w.) that were high in gills. Beside, kidney is determined as target tissue for Ni and V in B. grypus and for Pb in C. carpio, due to their high concentration. Zn levels in all tissues of C. carpio showed the highest concentrations in comparison to other fish species. Generally, accumulations of most of the studied elements
in B. grypus and B. sharpeyi were higher in females than in males, while in fillet and gonads of C. carpio, this trend was inverted. Bioaccumulation factors (BAFs) were determined for different tissues of fish species with respect
to elemental concentrations in sediment. BAFs results indicated that Zn, Pb, and Cu have higher BAF than other elements. Also
this investigation demonstrated that trace elements have different affinities with condition factor of studied fish species.
Gonadosomatic index (GSI) and Pb showed positive correlation together in both B. sharpeyi and B. grypus, respectively, in females and males. Moreover, females of C. carpio showed significantly positive relation of GSI and all studied elements. 相似文献