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1.
Detection and assessment of the impact of pollution on biological resources imply increasing research on early-warning markers such as metallothioneins (MTs) in metal exposure. In this paper, we have collated published information on the use of metallothioneins and metallothionein-like proteins (MTLPs) as biomarkers for environmental quality assessment in the Gulf of Gabès. In this area, some species of fish and bivalve were used as bioindicators of pollution. In these species, an induction of MTs/MTLPs by the essential metals such as Cu and Zn and the non-essential metals such as Cd was observed by different authors who suggest the potential use of these proteins as biomarkers. However, MT concentrations can be influenced by many biotic (sex, maturity stages, and tissues) and abiotic factors (temperature, salinity, and pH). This is essentially the case in field studies where many parameters can randomly affect MT levels, so the endogeneous regulation of MTs must be considered before using MTs as an indicator of heavy metal exposure. Moreover, the use of biomarker cannot be examined independently of the evaluation of techniques that enable its quantification. Therefore, the approach to the use of MTs/MTLP as biomarkers of exposure for an assessment of the physiological status of aquatic organisms is discussed in this paper.  相似文献   

2.
The geochemistry of coastal sediments of southern India was altered after the tsunami in 2004. A five-step sequential extraction procedure was applied to assess the effects of tsunami on mobility and redistribution of selected elements (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn). Ten surface sediments and three cores were analyzed for different metal fractions (exchangeable, carbonate, reduced, oxidized, and residual). Total metal concentrations increased in mangrove sediments after the tsunami, but their spatial distribution did not show significant variation (except Mn). The sediments were mixed by the tsunami, and there was lack of variation in metal concentrations in different fractions with depth (except Pb and Mn). High concentrations of Pb and Zn occurred in the oxide fractions, whereas Cu, Cr, Cd, and Ni were high in the organic and sulfide-rich fractions. Metals in the residual fraction (lattice bound) had the highest concentration suggesting their non-availability and limited biological uptake in the system. Most of the metals (except Mn) do not constitute a risk based on the different geochemical indices.  相似文献   

3.
The geochemical behavior of zinc, lead and copper from sulfidic tailings in a mine site with potential to generate acidic drainage (pyrite (55%) and sphalerite (2%)) is reported in this paper. The mining area is divided in two zones, considering the topographic location of sampling points with respect to the tailings pile: (a) outer zone, out of the probable influence of acid mine drainage (AMD) pollution, and (b) inner zone, probably influenced by AMD pollution. Maximum total ions concentrations (mg/L) measured in superficial waters found were, in the outer zone: As (0.2), Cd (0.9), Fe (19), Mn (39), Pb (5.02), SO4(2-) (4650), Zn (107.67), and in the inner zone are As (0.1), Cd (0.2), Fe (88), Mn (13), Pb (6), SO4(2-) (4,880), Zn (46). The presence of these ions that exceeding the permissible maximum limits for human consume, could be associated to tailings mineralogy and acid leachates generated in tailings pile.  相似文献   

4.
Surface soil samples collected from a Pb and Zn mining area in India were subjected to multi-elemental analysis by using inductively coupled plasma-atomic emission spectrometry. Multivariate statistical methods such as principal component analysis and cluster analysis, coupled with correlation coefficient analysis, were used to analyze the data and to apportion the possible sources of elements in soils of a metal mining area. Soils in this area have elevated heavy metal concentrations especially Pb, Zn, Mn, Cu, As, and Tl. Using principal component (PC) analysis, six components were extracted, out of which two PCs explaining 50.12% of total variance are more important. The first principal component with a high contribution of Ag, As, Be, Cd, Co, Cu, Mg, Mn, Ni, Pb, and Zn was deemed to be technogenic/anthropogenic component, and the second principal component, with high loadings for the five discerning variables (Al, Be, Cr, K, Li), was considered as lithogenic component. The third component having strong loadings of Ba, Ca, K, and Na is supposed to have a mixed origin (lithogenic as well as technogenic). Electrical conductivity and total organic matter were not correlated with any element and also have a strong loading in the fifth component which is probably the biomass and ions present in these soils. The findings of the principal component analysis were also substantiated by the cluster analysis. The present study would not only enhance our knowledge regarding the soil pollution status in the study area but would also provide us information to manage the sources of these elements in the study area.  相似文献   

5.
Soil quality assessment provides a tool for evaluating the sustainability of alternative soil management practices. Our objective was to develop the most sensitive soil quality index for evaluating fertilizer, farm yard manure (FYM), and crop management practices on a semiarid Inceptisol in India. Soil indicators and crop yield data from a long-term (31 years) fertilizer, manure, and crop rotation (maize, wheat, cowpea, pearl millet) study at the Indian Agricultural Research Institute (IARI) near New Delhi were used. Plots receiving optimum NPK, super optimum NPK and optimum NPK + FYM had better values for all the parameters analyzed. Biological, chemical, and physical soil quality indicator data were transformed into scores (0 to 1) using both linear and non-linear scoring functions, and combined into soil quality indices using unscreened transformations, regression equation, or principal component analysis (PCA). Long-term application of optimum inorganic fertilizers (NPK) resulted in higher soil quality ratings for all methods, although the highest values were obtained for treatment, which included FYM. Correlations between wheat (Triticum aestivum L.) yield and the various soil quality indices showed the best relationship (highest r) between yield and a PCA-derived SQI. Differences in SQI values suggest that the control (no NPK, no manure) and N only treatments were degrading, while soils receiving animal manure (FYM) or super optimum NPK fertilizer had the best soil quality, respectively. Lower ratings associated with the N only and NP treatments suggest that one of the most common soil management practices in India may not be sustainable. A framework for soil quality assessment is proposed.  相似文献   

6.
Anticipating the European Water Framework Directive (2000/60/EC), the Italian Government issued Legislative Decree n.152/99 which sets out rules for classifying the environmental status of national water bodies in order to achieve specific qualitative objectives by 2016. The most recent European Groundwater Directive (2006/118/EC), which was only recognized by Italy in early 2009 (Legislative Decree 30/09), requires such resources to be characterized from a qualitative standpoint and the risk of their being polluted by individual pollutants or groups of pollutants to be evaluated. This paper reports a simple methodology, based on easy-to-apply rules, for the rapid classification of groundwater, and the results of its application to the shallow aquifer of the plain of Tavoliere delle Puglie located in south Italy. Data collected during well-water monitoring campaigns carried out from 2002 to 2003 made it possible to assess the environmental status of the Tavoliere which, unfortunately, was found to be characterized by ??significant anthropic pressures on quality and/or quantity of groundwater and necessitating specific improvement actions??.  相似文献   

7.
8.
Accumulation dynamics and cellular locations of lead (Pb), zinc (Zn) and cadmium (Cd) were studied in Flavocetraria nivalis lichens near the former Black Angel Pb–Zn Mine in West Greenland. Natural resident thalli were collected from four dust-contaminated sites near the mine. In addition, thalli were taken from an uncontaminated reference site and transplanted to the contaminated sites followed by a collection 1 year after. Total thalli metal contents were determined, and thalli were subjected to a sequential extraction procedure. After 1 year of transplantation, total Pb thalli contents were significantly elevated compared with initial concentrations at all sites (for Zn and Cd contents only at the two sites closest to the mine). However, transplanted thalli contained significantly less Pb (26?±?12 %), Zn (64?±?13 %) and Cd (34?±?7 %) compared with resident thalli from these sites. Results from the sequential extraction procedure showed marked differences among Pb, Zn and Cd in the extracellular, intracellular and residual fraction. The lower total metal concentrations in transplanted compared with resident thalli at the contaminated sites were mostly due to a larger metal content bound in the residual fraction in resident thalli. In contrast, the metal content bound in the extracellular fraction were not significantly different in transplanted and resident thalli. The results indicate that extracellular-bound Pb, Zn and Cd in F. nivalis can be used as a proxy for recent (annual) atmospheric metal deposition whereas the large residual metal fraction in resident lichens indicate an accumulation of metal-containing particles in the thalli over time that includes several years of uptake.  相似文献   

9.
The growing population number and traffic loads, increasing environmental pressures, agricultural intensification, and the establishment of Mount Cameroon National Park demand farsighted environmental management in the region and the definition of a favorable ecological status. Since plants grow in the interface between soils and the atmosphere they can be used as passive biomonitors for the environmental quality. At the same time, the accumulation of nutrients and pollutants in crops is linked to human health, so that foliar elemental levels can be used as an integrative measure for environmental pollution and impact assessment. In the present study, we collected leaf samples of plantain, cassava, cocoyam, and maize on 28 sites at the southern flanks of Mt. Cameroon and determined 20 chemical elements. Air pollution in the study area comes from biomass and waste burning mainly, but emissions from traffic and a large refinery were believed to also play a significant role. However, spatial patterns in foliar elemental concentrations reflected the geochemistry rather than specific sources of pollution. Significant differences in foliar metal and nutrient levels were observed between the four species, indicating a different demand and uptake of specific elements. The results were compared to published data on nutrient concentrations in the tested species and the so-called reference plant. The data can be used as a baseline for future studies in plant nutrition and the environmental monitoring in inner tropical regions where these crops are grown.  相似文献   

10.
11.
This article presents the results of an investigation carried out on the Nilüfer stream located in the southern part of Marmara region in Turkey 1999–2003. It evaluates water quality and proposes local requirements to prevent aquatic pollution problems. The study took into account the seasonal influences of point and non-point discharges on the organic pollution levels of the stream. The results indicated sub-standard water quality in most parts of the stream. Untreated domestic wastewaters, industrial discharges and agricultural activities contributed to the total annual organic loading. This study reveals the importance of construction, operation, maintenance and legislation of wastewater collection and treatment programmes, as well as the need for strict control of point and non-point nutrient loads for the preservation of the Nilüfer stream's water quality. Appropriate strategies for the control of point and non-point pollution sources, amendments and enforcement of legislation should be developed.  相似文献   

12.
The environmental effects of the mining of lead–zinc mineralization in Enyigba area, Southern Benue trough were examined. The samples used for this study were obtained from abandoned mine sites, mine tailings, streams, hand-dug wells, mine pond and borehole. Collected samples were subjected to X-ray fluorescence, X-ray diffraction analyses, atomic absorption spectrometry and permeability tests. These were done using standard laboratory equipment and procedures. The concentrations of heavy metals present in analysed water samples fall below the world health organizations’ (WHO) acceptable limits. Conversely, the soil, mine tailings and stream sediments indicate appreciable pollution level by some potential toxic metals (PTMs). Consequently, the habitual use of these soils for construction purpose by inhabitants has possible health hazards. The shaly lithology underlying the area is increasingly affected by weathering and lateritization, thus improving its permeability and the easiness with which PTMs can be conducted to the water table by leachate. Regular monitoring assessment is recommended to ensure adherence of miners operating in the area to existing environmental laws.  相似文献   

13.
Linear alkylbenzene sulfonate (LAS) is a group of anionic surfactants employed in the formulation of laundry and cleaning products, with a global production rate of 4 million metric tons. Sediments from the Polish coast of the southern Baltic Sea were collected at ten stations. Total LAS concentrations, measured by high-performance liquid chromatography, were between 0.04 and 0.72 mg LAS·kg(-1) dry weight. Highest LAS concentrations were found in suspended matter collected from the Vistula River, sediment collected close to the Vistula River mouth and from the Gdańsk Deep, known as the depositional area. With the obtained environmental LAS concentrations, a risk assessment for this surfactant has been carried out, based on publicly available acute and chronic toxicity data in target organisms. The results indicated that LAS could pose a low risk for the existing benthic community applying worst case scenario assessment. This is the first time that levels of LAS have been measured in environmental samples of the southern Baltic Sea.  相似文献   

14.
The Yamaska River drainage basin in Quebec, Canada, is intensively farmed and heavily polluted with poorly treated domestic and industrial wastes. We investigated the responses of the resident and colonizing components of the benthic macroinvertebrate community to municipal/industrial versus agricultural pollution in the basin, and evaluated the performances of seven diversity and biotic indices for assessing water quality. Samples of riffle-dwelling, infaunal and colonizing invertebrates were collected from 13 stations representing a wide range of types and degrees of pollution using Surber, scoop and artificial substrate samplers. The data were summarized using the indices S (number of taxa), N (number of individuals), H (Shannon-Wiener's diversity index), D (Simpson's diversity index), BBI (Belgian Biotic Index), TBI (a modification of Hilsenhoff's Biotic Index), % CHIR (percentage of arthropods consisting of Chironomidae) and %OLIGO (percentage of total organisms consisting of Oligochaeta). Different components of the community generated somewhat different assessments and were, therefore, complementary. Community composition, expressed as the percentage of individuals contributed by major taxonomic groups, reflected the kinds of stresses at a station more consistently than did any of the indices. S and TBI came closest to ranking control, agricultural and municipal/industrial sites in accordance with our a priori classification, both between months and among sampling methods. %OLIGO usually separated municipal/industrial sites from control sites. Other indices were found to be less sensitive, accurate or temporally stable, or were otherwise inappropriate for use with certain sampling methods or for certain types of pollution. With most of our samples, all of the summary indices suggested that the impact of agricultural practices on stream ecosystems may be as severe as the impacts of municipal and industrial wastes.  相似文献   

15.
Noise mapping has been used as an instrument for assessment of environmental noise, helping to support decision making on urban planning. In Brazil, urban noise is not yet recognized as a major environmental problem by the government. Besides, cities that have databases to drive acoustic simulations, making use of advanced noise mapping systems, are rare. This study sought an alternative method of noise mapping through the use of geoprocessing, which is feasible for the Brazilian reality and for other developing countries. The area chosen for the study was the central zone of the city of Sorocaba, located in São Paulo State, Brazil. The proposed method was effective in the spatial evaluation of equivalent sound pressure level. The results showed an urban area with high noise levels that exceed the legal standard, posing a threat to the welfare of the population.  相似文献   

16.
Changes in the phytoplankton biomass (chlorophyll a), production rate, and species composition were studied over two seasons using the time series measurements in the northern limb of the Cochin estuary in relation to the prevailing hydrological conditions. The present study showed the significant seasonal variation in water temperature (F = 69.4, P < 0.01), salinity (F = 341.93, P < 0.01), dissolved inorganic phosphorous (F = 17.71, P < 0.01), and silica (F = 898.1, P < 0.01) compared to nitrogen (F = 1.646, P > 0.05). The uneven input of ammonia (3.4–224.8 μM) from upstream (Periyar River) leads to the inconsistency in the N/P ratio (range 6.8–262). A distinct seasonality was observed in Si/N (F = 382.9, P < 0.01) and Si/P (F = 290.3, P < 0.01) ratios compared to the N/P ratio (F = 1.646, P > 0.05). The substantial increase in chlorophyll a (average, 34.8 ± 10 mg m???3) and primary production (average, 1,304 ± 694 mg C m???3 day???1) indicated the mesotrophic condition of the study area during the premonsoon (PRM) and it was attributed to the large increase in the population of nanoplankton (size < 20 μ ) such as Skeletonema costatum, Thalassiosira subtilis, Nitzschia closterium, and Navicula directa. In contrast, during the post monsoon (PM), low chlorophyll a concentration (average, 9.3 ± 9.2 mg m???3) and primary production (average, 124 ± 219 mg C m???3 day???1) showed heterotrophic condition. It can be stated that favorable environmental conditions (optimum nutrients and light intensity) prevailing during the PRM have enhanced the abundance of the nanoplankton community in the estuary, whereas during the PM, the light limitation due to high turbidity can reduce the nanoplankton growth and abundance, even though high nutrient level exists.  相似文献   

17.
Section 303(d) of the Clean Water Act requires States and Tribes to list waters not meeting water quality standards. A total maximum daily load must be prepared for waters identified as impaired with respect to water quality standards. Historically, the management of pollution in Minnesota has been focused on point-source regulation. Regulatory effort in Minnesota has improved water quality over the last three decades. Non-point source pollution has become the largest driver of conventional 303(d) listings in the 21st century. Conventional pollutants, i.e., organic, sediment and nutrient imbalances can be identified with poor land use management practices. However, the cause and effect relationship can be elusive because of natural watershed-system influences that vary with scale. Elucidation is complex because the current water quality standards in Minnesota were designed to work best with water quality permits to control point sources of pollution. This paper presents a sentinel watershed-systems approach (SWSA) to the monitoring and assessment of Minnesota waterbodies. SWSA integrates physical, chemical, and biological data over space and time using advanced technologies at selected small watersheds across Minnesota to potentially improve understanding of natural and anthropogenic watershed processes and the management of point and non-point sources of pollution. Long-term, state-of-the-art monitoring and assessment is needed to advance and improve water quality standards. Advanced water quality or ecologically-based standards that integrate physical, chemical, and biological numeric criteria offer the potential to better understand, manage, protect, and restore Minnesota’s waterbodies.  相似文献   

18.
Cd, Co, Cr, Cu, Mn, Ni, Zn, and Pb were measured in feather samples of adult, subadult, and juvenile of Larus dominicanus, sampled in the Florianólis, SC, in the south of Brazil in December 2005, by flame atomic absorption spectrophotometry. The average of the distribution of Cd concentration in adult feathers (0.072 μg g???1) was significantly different than that found in juvenile feathers (0.021 μg g???1). Cu concentration averages were not significantly different between adults (13.30 μg g???1), subadults (9.67 μg g???1), and juveniles (13.76 μg g???1). For adults and juveniles there was significant difference in feather concentrations for Cd, Co, Cr, Ni, and Pb. The distribution of Mn concentration averages in feathers differs between adults (11.36 μg g???1) and juveniles (1.184 μg g???1). Ni concentration averages of adults (5.92 μg g???1) were significantly higher than those of juveniles (2.23 μg g???1). For Pb, concentration averages were significantly higher in adults (7.53 μg g???1) than in juveniles (1.47 μg g???1). The concentration of Co and Cr in juvenile and subadults are statistically different when compared with the adults. In the present study, levels of Cd, Co, Cr, Mn, Ni, Zn, and Pb increased with age. The concentrations of essential trace elements in L. dominicanus were generally comparable to values reported in other studies. With non-essential metals (Cd, Pb, and Ni), in our study, L. dominicanus had lower values than those reported for their northern Atlantic counterparts.  相似文献   

19.
20.
Activities of 21?Po and 21?Pb in whole-body and in various tissues of brachyuran crabs collected along the Kudankulam coast were studied. A non-uniform distribution of these radionuclides was observed between the various tissues. Of all the tissues, 21?Po and 21?Pb were found to accumulate more in the hepatopancreas and intestine. Among the crabs studied, Charybdis lucifera registered higher 21?Po and 21?Pb activity. Muscle tissue in all the species registered lower activity. The 21?Po/21?Pb activity ratio was found to be greater than unity. The biological concentration factor for organs varied between ~ 10? and 10? for 21?Po and ~102 and 10? for 21?Pb. A significant variation in the accumulation of 21?Po and 21?Pb was noted between species and between seasons (p < 0.05). The mean whole-body internal dose ranged from 1.42 to 6.86 μGy h?1 for 21?Po and from 3.0 × 10?3 to 8.0 × 10?3 μGy h?1 for 21?Pb. The external dose for 21?Po and 21?Pb was 2.41 × 10?? to 5.76 × 10?? μGy h?1 and 4.14 × 10?? to 8.26 × 10?? μGy h?1, respectively. The activity levels recorded are in agreement with values recorded in related organisms in other parts of the world. The total committed effective dose due to the intake of both radionuclides ranged from 80.3 to 871.7 μSv y?1. The median dose calculated due to 21?Po and 21?Pb in certain crabs in Kudankulam is less and would not pose any significant radiological impact on health or a cancer risk to the public, and the seafood is considered safe for human consumption.  相似文献   

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