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1.
Methodologies for the environmental analysis of total antimony and aqueous chemical speciation are critically reviewed, including preparation techniques for aqueous and solid matrices and the determination of solid state partitioning and recommendations are given for future research directions. Concentrations of total antimony commonly present in aqueous and solid environmental samples are readily determined using present day analytical techniques. This has resulted primarily from technological advances in microwave digestion for solid matrices and the development of plasma based analyte detection systems. ICP-AES and ICP-MS techniques are both utilised for the environmental analysis of total antimony concentrations. However, ICP-MS is increasingly favoured as a result of reduced spectral interferences and the potential for analyte detection in the pg mL(-1) range. Determination of aqueous antimony speciation presents a number of complex analytical challenges and highly selective separation and identification techniques are required prior to detection. The majority of published techniques including common applications of hydride generation are insufficiently selective for the determination of intrinsic chemical speciation and often only oxidation state data are obtained. The recent in-line applications of HPLC-ICP-MS offer the potential for highly selective separations of aqueous antimony species and determination of detailed chemical speciation data. However, considerable development work is required to optimise chromatographic separations and identify uncharacterised species resident in environmental systems. Analytical techniques to aid the determination of antimony's associations with solid environmental matrices include the application of chemical extraction procedures and leaching experiments. To date, this area of analytical research has received little attention and further studies are required to elucidate this aspect of antimony's environmental chemistry.  相似文献   

2.
Biomonitoring and environmental management   总被引:2,自引:0,他引:2  
The advantages of biological monitoring of the environment have been long recognised. Direct measurements on biota of importance rather than the use of chemical surrogates, integration over time and the ability to measure the perhaps subtle changes brought about by minor or intermittent pollution have all been propounded as adantages.There appear to be a variety of barriers to the wider adoption of biomonitoring approaches. The perception that biomonitoring takes longer and is more expensive than chemical monitoring. The idea that chemical measurements are an adequate surrogate for direct measurements of biological change. The belief that interpretation of biological data is complex and uncertain in comparison with chemical data. These widely held myths are addressed and some broad principles to guide the development of biomonitoring programs are developed.  相似文献   

3.
The environmental restoration of terrestrial ecosystems helps to protect the natural world and enhances sustainable land resource development. Modern and efficient approaches for the conservation of ecological functions must be established for more severe land degradation. In this paper, artificial intelligence assisted intelligent planning framework has been proposed to manage the environmental restoration of the terrestrial ecosystem. Facilitating balance of ecosystem service provision, demand, and using machine learning to dynamically build Biological Retreat Configuration (BRCs) that helps better to apprehend the influence of urban growth on environment-related procedures. Such factors can be used as a theoretical reference in the combination of commercial development and eco-friendly conservation. The BRC of the metro area of Changsha Zhuzhou Xiangtan (CZX) has been developed in this study to classify ecological sources using the Bayesian network model efficiently. Using the Least Collective Resistance (LCR) model and circuit theory, the environmental passage and environmental strategy points were established. The BRC was developed by integrating seven environmental factors with 35 ecological policy points. The results showed that the supply and demand of organic unit services (EUS) were spatially decoupled with the deterioration in locations with a significant EUS trend. The urban agglomeration's environmental sources and ecological corridors have been primarily located in forests and waters. The terrestrial environmental pathway has been scattered around the outer edge of the region, while the aquatic green corridor has been extended over the whole town. The environmentally sensitive areas were located primarily around the borders of the growing region and the intersections between land development and forest area. Finally, environmental components have been mainly identified in existing zones of biological defense, which support the effectiveness of Machine Learning (ML) in green sources forecasting and offer novel insight into the development of urban BRCs. The proposed approach has proven to be effective for the planning of assessing environmental restoration in terrestrial ecosystems.  相似文献   

4.
Asian clam Corbicula fluminea, the amphipod Dikerogammarus villosus and the macrophyte Nuphar lutea were tested for investigating spatial and temporal variability in the bioavailability of tin and arsenic in the River Lippe, Germany. Samples were collected from September 2002 to May 2003 at a tin polluted site (source pollution) and a reference site. Additional screening sampling was carried out twice in April 2003 to test the extent of As and Sn concentration in periphyton (aufwuchs) samples. Accumulated Sn and As concentrations were measured with ICP-MS after sample processing (dissection, cryo-milling) and digestion. Quality control was performed by parallel analysis of three certified reference materials. Measurable As and Sn contents in plant tissues were only detectable in roots (below 30 microg kg(-1) and 20 microg kg(-1) for As and Sn, respectively). Homogenates from C. fluminea and D. villosus tissues showed site-dependent trace metal contents. Elevated bioavailability of Sn is present downstream of the sewage discharge of the world's biggest producer of tributyltin (TBT) at Luenen (northern Ruhr region). In comparison to C. fluminea, D. villosus shows higher concentrations of tin in samples from both sites. Arsenic concentrations in C. fluminea remain constant with increasing shell size, whereas tin shows a size-dependent accumulation. The results indicate that Corbicula fluminea and Dikerogammarus villosus are suitable passive biomonitoring organisms for Sn, but As levels might be actively regulated. The concentration of tin in the periphyton (aufwuchs) samples was found to be much higher in samples from a contaminated site (428 +/- 63 vs. 1949 +/- 226 microg kg(-1)).  相似文献   

5.
A survey of the methods of boindication of heavy metals in terrestrial ecosystems and their effectiveness for predicting the consequences of environmental stress on organisms is presented. Two main inputs of heavy metals for terrestrial ecosystems have been considered: airborne and soil-borne. Airborne metals can be monitored due to physical adsorption on plant surfaces or due to chemical exchange processes in cell walls. Active biomonitoring widely uses both aspects, however, without predictive values. Meaningful bioindication of soilborne heavy metals can only be achieved by passive monitoring. Due to the different functions of heavy metals in organisms-micronutrients and trace elements-the knowledge of natural background values is important, considering the qualitative aspects of metals in the soil. In exceptional situations morphological and anatomical changes of plant organs will facilitate bioindication; in every case chemical analysis of the concentration of heavy metals is an essential part of the monitoring program. A long-term exposure of organisms to heavy metals will influence the genetic structure of populations. Therefore measurement of heavy metal tolerance of plants has to be a standard procedure in monitoring programs.  相似文献   

6.
An attempt is made to determine the bioavailability of persistent organic pollutants (POP's) in environmental matrices. The approach is based on the use of the Hildebrand Solubility Parameter, and its individual parameters of hydrogen bonding, dispersion and polarity to select weak and strong solvents to extract POP's from soil matrices. The approach has been applied to both spiked soils and certified reference materials. Initial results indicate that it is possible to fractionate POP's from soil matrices based on their ability to be extracted from soil by particular solvents.  相似文献   

7.
Intact natural ecosystems are fairly stable objects. In the course of natural selection proceeding against the background of synecological interactions (trophic, competitive, symbiotic, etc.), a respective complex of coadapted species forms, each being maximally accommodated to its habitat. Such a complex is of specific composition and possesses stable structural characteristics. Fairly regular processes of changes in these characteristics, specific to the given type of environmental conditions, are observed in non-stationary cases.We analyze probable causes of the loss of stability in natural systems exposed to man made impacts of a global scale, in particular structural instability, landscape (distributive) instability, and conductive instability.The study of the mechanisms ensuring biosphere sustainability and stability of its elements is a vital ecological problem. There are applied aspects in the problem solution since identification of man-induced instability is feasible only on the basis of precise knowledge of the natural mechanisms of weak points of the relevant natural process. This circumstance makes the problem of stability one of the focal questions of applied ecology.  相似文献   

8.
Assessment of the food chain mobility of heavy metals inthe natural ecosystem receives more attention nowadays. Inthe present study, mulberry-silkworm food chain has beenfocused as a templet to assess the biomobility of heavymetals in soil-higher plant-insect hierarchy. Both in thecase of Cd and Cu treatments, higher mobility wasobserved in the level-1 (soil–root) followed by level-3(leaf–larva), level-4 (larvae–faecal) and level-2(root–leaf). Consequently, roots accumulated more amountsof Cd and Cu, with a limited transport to the leaves.Among the two metals (Cd and Cu) tested, in the plant,the transfer potential of Cd exceeds that of Cu. Whereasin the case of leaf–larval transfer, Cu precedes overCd. Accumulation of Cd and Cu in all the levels (1–4)tested showed a concentration dependent increase, except inthe level 4 (larva–faecal) of Cd treatment where adeclining trend was noticed.  相似文献   

9.
The Croatian part of the Danube River extends over 188 km and comprises 58 % of the country’s overall area used for commercial freshwater fishing. To date, the heavy metal contamination of fish in the Croatian part of the Danube has not been studied. The main purpose of this study was to determine heavy metal levels in muscle tissue of sampled fish species and to analyze the measured values according to feeding habits of particular groups. Lead ranged from 0.015 μg?1 dry weight in planktivorous to 0.039 μg?1 dry weight in herbivorous fish, cadmium from 0.013 μg?1 dry weight in herbivorous to 0.018 μg?1 dry weight in piscivorous fish, mercury from 0.191 μg?1 dry weight in omnivorous to 0.441 μg?1 dry weight in planktivorous fish and arsenic from 0.018 μg?1 dry weight in planktivorous to 0.039 μg?1 dry weight in omnivorous fish. Among the analyzed metals in muscle tissue of sampled fish, only mercury exceeded the maximal level (0.5 mg kg?1) permitted according to the national and EU regulations determining maximum levels for certain contaminants in foodstuffs, indicating a hazard for consumers of fish from the Danube River.  相似文献   

10.
Trace transition metals (Fe3?+?, Mn, Cu, Cd, Co, Zn, Ni) in environmental samples were analyzed by chelation ion chromatography using a mixed bed ion-exchange column with pyridine-2,6-dicarboxylic acid (PDCA) and oxalic acid as eluent and large volume direct injection (1,000 ??l). The two eluents, PDCA and oxalic acid, were tested, and repeatability and detection limits were compared. The total analysis time was ~15 min. The separation with PDCA was more successful than that obtained with acid oxalic. It was observed that utilizing PDCA resulted in lower detection limits, higher repeatability, and a quantitative detection of Cd and Mn, which coelute as a single peak when using the oxalic acid. At last, the PDCA calibration graphs resulted linear (r 2?>?0.999) in the range 0.4?C1,000 ??g/L. The procedure was applied to the analysis of metals in soils and in water samples. The results obtained from the analysis of natural waters have demonstrated that the method is simple and efficient, therefore, can be used for the determination of metals in natural waters using a continuous and automatic monitoring system.  相似文献   

11.
This paper describes the measurement of total antimony and antimony species in "real world" mine contaminated sediments using ICPMS and HPLC-ICPMS. Low and high temperature microwave extraction procedures (90 degrees C and 150 degrees C, respectively) using a range of nitric-hydrochloric acid combinations were examined as to their efficacy to extract antimony from six mine contaminated soils and a certified reference material. The use of the higher temperature with nitric-hydrochloric acid (1:2 (v/v)) was suitable to release antimony from sediments and the certified reference material, NIST 2710 Montana soil. Antimony concentrations obtained using this acid mixture were similar to those obtained using a more aggressive extraction with nitric, hydrochloric, perchloric and hydrofluoric acid mixture. A 25 mM citric acid solution at 90 degrees C for 15 min extracted 47-78% of antimony from soils. A Hamilton PRP X-100 anion exchange column with 20 mM EDTA mobile phase, pH 4.5, flow rate 1.5 mL min(-1) and column temperature of 50 degrees C was used to separate antimony species. Column recoveries ranged from 78-104%. The predominant form of antimony was Sb(5+). Little conversion of Sb(5+) occurred (<5%) during extraction, however, significant conversion of Sb(3+) occurred (approximately 36%). The extraction of antimony species with citric acid should be useful in the determination of inorganic antimony available to plants, as plants commonly excrete carboxylic acids, including citric acid, into their rhizospheres to mobilise trace elements for nutritional purposes.  相似文献   

12.
Pentachlorophenol (PCP) has been used as a herbicide, biocide and preservative worldwide since the 1930s and as a result, extensive and prolonged contamination exists. The environmental impact increases when its many degradation products are taken into consideration. A number of chloroanisols and their related chlorophenols have been found in cork slabs collected from Portuguese oak tree forests before stopper manufacturing, and contamination by PCP and polychlorinated anisole (PCA) has been detected in Canadian forests. It is suggested that the use of polychlorinated phenols, in particular PCP, is thought to be a cause of the cork taint problem in wine, a major socio-economic impact not only for industry but on sensitive and highly biodiverse ecosystems. It also highlights particular issues relating to the regional regulation of potentially toxic chemicals and global economics world wide. To fully understand the impact of contamination sources, the mechanisms responsible for the fate and transport of PCP and its degradation products and assessment of their environmental behaviour is required. This review looks at the current state of knowledge of soil sorption, fate and bioavailability and identifies the challenges of degradation product identification and the contradictory evidence from field and laboratory observations. The need for a systematic evaluation of PCP contamination in relation to cork forest ecosystems and transfer of PCP between trophic levels is emphasised by discrepancies in bioaccumulation and toxicity. This is essential to enable long term management of not only transboundary contaminants, but also the sustainable management of socially and economically important forest ecosystems.  相似文献   

13.
In order to control the quality of rare earth determinations in environmental matrices, the Standards, Measurements and Testing Programme (formerly Community Bureau of Reference, BCR) of the European Commission has started a project, the final aim of which is to certify four types of matrices (tuna muscle, mussel tissue, aquatic plant and estuarine sediment) for their contents of a range of rare earth elements (Sc, Y and the lanthanides: La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu). The elements U and Th were added to the study. The first part of this project consisted of an interlaboratory study which aimed to test the feasibility of preparation of environmental reference materials and to detect and remove most of the pitfalls observed in rare earth determinations. This paper presents the preparation of the four matrices for the intercomparison study and for the candidate reference material. The main results are presented of the interlaboratory study that was carried out prior to the certification campaign. This collaborative trial is the first attempt ever carried out at this scale to evaluate the state-of-the-art of rare earth determinations in the environment. Its impact on the improvement of chemical measurements will have positive effects on the comparability of data necessary for environmental monitoring.  相似文献   

14.
Up to now only very few studies in biomonitoring of organic air pollutants have been published taking into account the strong influence mean temperatures have on the accumulation process into plants during the course of the exposition. Temperature governed sorption as well as the plants vitality pose a major source of uncertainty making inter-study comparisons difficult. Different surface-to-volume ratios of plant foliage lead to strongly varying concentration effects in different plant species. Moreover a plants content of waxes and lipids must be considered in order to relate xenobiotic concentrations to the compounds being most efficient in the bioaccumulation process. Some of these factors are evaluated in regard to the use of plants as biomonitors for organic air pollutants. Another aim is to deduce the mean ambient gas phase concentrations from PAH concentrations determined in the biomonitor plants using vegetation-air partitioning coefficients which have been corrected for temperature dependent sorption as well as the plants lipid content. Restrictions of such approaches and methods of biomonitoring in general are discussed.  相似文献   

15.
生物监测在跨界河流中的应用进展   总被引:1,自引:0,他引:1  
综合分析了生物监测在跨界河流流经国家间的协调管理、生物类群的选择以及监测技术的选择方面所面临的问题;选择欧洲多瑙河、亚洲湄公河以及非洲尼日尔河等跨界河流作为典型案例,对比分析使用不同生物类群(例如底栖动物、浮游藻类以及鱼类)进行跨界河流生物监测的技术方法,阐述了跨界生物监测项目中的资金来源、管理办法和运行机制等;并对未来的跨界河流生物监测提出建议,以期为中国的跨界河流生物监测提供实践依据。  相似文献   

16.
Using clean lab methods and protocols developed for measuring Sb in polar snow and ice, we report the abundance of Sb in fifteen brands of bottled water from Canada and forty-eight from Europe. Comparison with the natural abundance of Sb in pristine groundwaters, water bottled commercially in polypropylene, analyses of source waters prior to bottling, and addition of uncontaminated groundwater to PET bottles, provides unambiguous evidence of Sb leaching from the containers. In contrast to the pristine groundwater in Ontario, Canada containing 2.2 +/- 1.2 ng l(-1) Sb, 12 brands of bottled natural waters from Canada contained 156 +/- 86 ng l(-1) and 3 brands of deionized water contained 162 +/- 30 ng l(-1); all of these were bottled in PET containers. Natural water from Ontario bottled in polypropylene contained only 8.2 +/- 0.9 ng l(-1). Comparison of three German brands of water available in both glass bottles and PET containers showed that waters bottled in PET contained up to 30 times more Sb. To confirm that the elevated Sb concentrations are due to leaching from the PET containers, water was collected in acid-cleaned LDPE bottles from a commercial source in Germany, prior to bottling; this water was found to contain 3.8 +/- 0.9 ng l(-1) Sb (n = 5), compared with the same brand of water purchased locally in PET bottles containing 359 +/- 54 ng l(-1) (n = 6). This same brand of water in PET bottles, after an additional three months of storage at room temperature, yielded 626 +/- 15 ng l(-1) Sb (n = 3). Other German brands of water in PET bottles contained 253-546 ng l(-1) Sb (n = 5). The median concentration of Sb in thirty-five brands of water bottled in PET from eleven other European countries was 343 ng l(-1) (n = 35). As an independent check of the hypothesis that Sb is leaching from PET, the pristine groundwater from Canada (containing 2.2 +/- 1.2 ng l(-1) Sb) was collected from the source using PET bottles from Germany: this water contained 50 +/- 17 ng l(-1) Sb (n = 2) after only 37 days, even though it was stored in the refrigerator, and 566 ng l(-1) after six months storage at room temperature.  相似文献   

17.
This paper describes our experiences with undertaking measurements of total antimony and antimony speciation in algae, plant and animal tissues. Digestion with nitric acid alone is suitable to release antimony from animal tissues. When organisms have high silica contents, e.g. some plants and algae, the addition of tetrafluorboric acid is required to dissolve silica as some antimony is retained by silica in extracts. Antimony in digested extracts is present as Sb5+ and hydride generation procedures can be used to determine total antimony concentrations, as total antimony in extracts will not be under estimated. Relatively non-aggressive solvents such as water, dilute nitric acid, sodium hydroxide and enzymes remove highly variable amounts of antimony (2-84%) from algae, plant and animal tissues. Addition of Sb3+ and Sb5+ to NIST CRM 1572 Citrus Leaves, pre- and post-extraction with water showed that Sb3+ is oxidised to Sb5+ while Sb5+ is redistributed amongst binding sites giving rise to artefacts. DOLT-2 and algae extracts indicated the presence of only inorganic antimony. A moss sample had inorganic antimony and a number of unknown antimony species in extracts. Future studies should explore the nature of the binding of antimony in tissues as solvents commonly used to extract metals and metalloids from algae, plant and animal tissues are not appropriate.  相似文献   

18.
19.
The purpose of the biomonitoring project in the Nature Conservancy in the Czech Republic is to obtain information on long-term development of some selected living components of ecosystems in protected areas. A survey of methods was conducted to select the monitoring areas as well as to study birds, epigean, vegetation and water communities (a minimal programme). A system for the monitoring areas and data storage and processing (to gather a body of evidence) was established. Simultaneously, close linkage with abiotic factor monitoring is planned. The project has been carried out by the Czech Institute for Nature Conservation.  相似文献   

20.
The aim of this study was to detect the presence and determine the residue levels of DDT, lindane, endrin and polychlorinated biphenyls (PCBs) in the liver of wild boars from the area of West Pomerania, NW Poland; to determine the activity of glutathione S-transferase (GST) as a biomarker of biological response and to assess the toxicological risk for consumers of the wild boar offal. The presence of pesticide residues and PCBs was found in all examined liver samples. The highest concentration was observed for endrin, and then, the descending order was PCBs >DDTs >lindane >dl-PCBs. The mean hepatic concentrations of endrin, PCBs, DDTs and lindane were 117.28, 78.59, 67.95 and 7.24 ng/g lipid weight, respectively. Among the dioxin-like PCB congeners, 118 and 156 were dominant in liver samples. The mean toxic equivalent (TEQ) level calculated for dl-PCBs was 2.10?±?1.11 pg WHO-PCB-TEQ/g. There was a statistically significant (p?<?0.05) negative correlation between the concentration of lindane, DDTs and PCBs (as a sum of indicator congeners) in the liver and in the activity of GST. However, GST activities showed no significant correlation with any of the dl-PCBs. In five boar liver samples, the levels of certain organochlorine compounds exceeded the maximum residue levels (MRLs). In one sample, the MRLs were exceeded simultaneously for PCBs, endrin and DDTs and in another one—for endrin and DDTs. In the remaining three samples, only PCB levels were exceeded.  相似文献   

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