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1.
Duplicate samples of the two terrestrial moss species Hylocomium splendens and Pleurozium schreberi, which are widely used to monitor airborne heavy metal pollution, have been collected from eight catchments spread over a 1,500,000 km2 area in northern Europe. These were analysed for a total of 38 elements by inductively coupled plasma-mass spectrometry, inductively coupled plasma-atomic emission spectrometry and cold vapour-atomic absorption spectometry techniques. Results show that the moss species can be combined without interspecies calibration for regional mapping purposes. For the majority of elements the observed within-catchment variation is large--big composite samples over a large area should thus be collected when moss is to be used for monitoring purposes. For the majority of elements the input of dust governs moss chemistry. For a reliable 'contamination' signal over a sizeable area a major source is needed. Some elements show a dependence on climate/vegetation zone. In coastal areas the input of marine aerosols will alter the chemical signal obtained from moss samples.  相似文献   

2.
S-concentrations were determined in 9 different sample materials (precipitation (rain and snow), vegetation, O-, E-, B- and C- horizon pf podzols, streams water and ground water) collected in eight small catchments (10-30 km2) at different distances from major SO2 point-source emitters on the Kola Peninsula, Russia. Comparison of the results from these materials, representing different compartments of the ecosystems under varying natural conditions leads to a better understanding of sources, cycling and fate of S in the Arctic environment. More than 300,000 t of SO2 emitted annually from the Kola smelters affect the air quality over a large area. Arctic climatic conditions (cold and dry) and the remote location of the emitters results in considerably lower S-deposition values than those observed in central Europe. The pathways of atmospheric S-deposition in the terrestrial environment vary significantly from summer to winter because different compartments of the ecosystems, with a different capability to accumulate S, are active. The actual S-flux is altered by every component of the ecosystem. When estimating the total S-deposition this effect must be considered.  相似文献   

3.
This study aims to determine the source apportionment of surfactants in marine aerosols at two selected stations along the Malacca Straits. The aerosol samples were collected using a high volume sampler equipped with an impactor to separate coarse- and fine-mode aerosols. The concentrations of surfactants, as methylene blue active substance and disulphine blue active substance, were analysed using colorimetric method. Ion chromatography was employed to determine the ionic compositions. Principal component analysis combined with multiple linear regression was used to identify and quantify the sources of atmospheric surfactants. The results showed that the surfactants in tropical coastal environments are actively generated from natural and anthropogenic origins. Sea spray (generated from sea-surface microlayers) was found to be a major contributor to surfactants in both aerosol sizes. Meanwhile, the anthropogenic sources (motor vehicles/biomass burning) were predominant contributors to atmospheric surfactants in fine-mode aerosols.  相似文献   

4.
A P Deshmukh  B Chefetz  P G Hatcher 《Chemosphere》2001,45(6-7):1007-1022
Chemical composition of coastal marine sedimentary organic matter (SDOM) is a function of natural and anthropogenic inputs to the system. In this study a combination of analytical techniques: 13C nuclear magnetic resonance (NMR), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and tetramethylammonium hydroxide thermochemolysis-gas chromatography/mass spectrometry (TMAH thermochemolysis-GC/MS) were used to study the contribution of hydrophobic organic contaminants and terrestrial OM to the SDOM. Sediments were collected from two sites in the San Diego Bay: Paleta Creek, which is contaminated, and Coronado Cayes, which is relatively pristine. Concentrations of polycyclic aromatic hydrocarbons (PAHs) at both sites, as determined by ultrasonically assisted lipid extraction are found to be higher in the surface layer, to generally decrease with depth, and to be present at about two orders of magnitude higher concentration at the contaminated site as compared to the pristine site. The sediment samples were partially deashed with HF/HCI treatment before further analysis. 13C-NMR spectra of the Paleta Creek samples show a higher aromatic carbon content and a distinct phenolic carbon peak. This suggests a large input from terrestrial carbon (lignin). Data from both Py-GC/MS and TMAH thermochemolysis-GC/MS support this and indicate the presence of lignin-derived residues, primarily of the guaiacyl type at the contaminated site. In contrast, SDOM at the Coronado Cayes site exhibits less terrestrial input. In general, the SDOM resembles soil OM rather than typical marine SDOM. Chemical analyses of the lipid-extracted, partially deashed sediments, does not reveal the presence of any PAHs.  相似文献   

5.
Fine particulate matter (PM2.5) concentrations at the Middle Adriatic coastal site of Croatia were affected by different air-mass inflows and/or local sources and meteorological conditions, and peaked in summer. More polluted continental air-mass inflows mostly affected the area in the winter period, while southern marine pathways had higher impact in spring and summer. Chemical characterization of the water-soluble inorganic and organic ionic constituents is discussed with respect to seasonal trends, possible sources, and air-mass inputs. The largest contributors to the PM2.5 mass were sea salts modified by the presence of secondary sulfate-rich aerosols indicated also by principal component analysis. SO42− was the prevailing anion, while the anthropogenic SO42− (anth-nssSO42−) dominantly constituted the major non-sea-salt SO42− (nssSO42−) fraction. Being influenced by the marine origin, its biogenic fraction (bio-nssSO42−) increased particularly in the spring. During the investigated period, aerosols were generally acidic. High Cl− deficit was observed at Middle Adriatic location for which the acid displacement is primarily responsible. With nssSO42− being dominant in Cl− depletion, sulfur-containing species from anthropogenic pollution emissions may have profound impact on atmospheric composition through altering chlorine chemistry in this region. However, when accounting for the neutralization of H2SO4 by NH3, the potential of HNO3 and organic acids to considerably influence Cl− depletion is shown to increase. Intensive open-fire events substantially increased the PM2.5 concentrations and changed the water-soluble ion composition and aerosol acidity in summer of 2015. To our knowledge, this work presents the first time-resolved data evaluating the seasonal composition of water-soluble ions and their possible sources in PM2.5 at the Middle Adriatic area. This study contributes towards a better understanding of atmospheric composition in the coastal Adriatic area and serves as a basis for the comparison with future studies related to the air quality at the coastal Adriatic and/or Mediterranean regions.  相似文献   

6.
Coastal habitats are situated on the border between land and sea, and ecosystem structure and functioning is influenced by both marine and terrestrial processes. Despite this, most scientific studies and monitoring are conducted either with a terrestrial or an aquatic focus. To address issues concerning climate change impacts in coastal areas, a cross-ecosystem approach is necessary. Since habitats along the Baltic coastlines vary in hydrology, natural geography, and ecology, climate change projections for Baltic shore ecosystems are bound to be highly speculative. Societal responses to climate change in the Baltic coastal ecosystems should have an ecosystem approach and match the biophysical realities of the Baltic Sea area. Knowledge about ecosystem processes and their responses to a changing climate should be integrated within the decision process, both locally and nationally, in order to increase the awareness of, and to prepare for climate change impacts in coastal areas of the Baltic Sea.  相似文献   

7.
The geochemistry of PM10 filter samples collected at sea during the Scholar Ship Atlantic–Mediterranean 2008 research cruise reveals a constantly changing compositional mix of pollutants into the marine atmosphere. Source apportionment modelling using Positive Matrix Factorization identifies North African desert dust, sea spray, secondary inorganic aerosols, metalliferous carbon, and V–Ni-bearing combustion particles as the main PM10 factors/sources. The least contaminated samples show an upper continental crust composition (UCC)-normalised geochemistry influenced by seawater chemistry, with marked depletions in Rb, Th and the lighter lanthanoid elements, whereas the arrival of desert dust intrusions imposes a more upper crustal signature enriched in “geological” elements such as Si, Al, Ti, Rb, Li and Sc. Superimposed on these natural background aerosol loadings are anthropogenic metal aerosols (e.g. Cu, Zn, Pb, V, and Mn) which allow identification of pollution sources such as fossil fuel combustion, biomass burning, metalliferous industries, and urban–industrial ports. A particularly sensitive tracer is La/Ce, which rises in response to contamination from coastal FCC oil refineries. The Scholar Ship database allows us to recognise seaborne pollution sourced from NW Africa, the Cape Verde and Canary islands, and European cities and industrial complexes, plumes which in extreme cases can produce a downwind deterioration in marine air quality comparable to that seen in many cities, and can persist hundreds of kilometres from land.  相似文献   

8.
Sedimentary hydrocarbons have been studied quantitatively and qualitatively in 16 stations of the Bay of Fort de France (Martinique). Hydrocarbon levels ranged from 54 to 1045 mg kg(-1) sed. dry weight. Origin of hydrocarbons are multiple: biogenic (terrestrial inputs), pyrolytic (residues of natural or anthropogenic combustions), diagenetic and anthropogenic (petroleum contamination). Generally high levels of hydrocarbons are not associated to a petroleum contamination. The main source of hydrocarbons in the mangrove coastal zones of the Bay of Fort de France seems to be the early diagenetic degradation products of 3-oxytriterpenoids. Excepted two stations, petroleum contamination is very low or absent.  相似文献   

9.
Rainwater contains a complex mixture of organic compounds which may influence climate, terrestrial and maritime ecosystems and thus human health. In this work, the characteristics of DOM of bulk deposition at a coastal town on the southwest of Europe were assessed by UV–visible and three-dimensional excitation–emission matrix fluorescence spectroscopies and by dissolved organic carbon (DOC) content. The seasonal and air mass trajectory effects on dissolved organic matter (DOM) of bulk deposition were evaluated. The absorbance at 250 nm (UV250nm) and integrated fluorescence showed to be positively correlated with each other, and they were also positively correlated to the DOC in bulk deposition, which suggest that a constant fraction of DOM is likely to fluoresce. There was more chromophoric dissolved organic matter (CDOM) present in summer and autumn seasons than in winter and spring. Bulk deposition associated with terrestrial air masses contained a higher CDOM content than bulk deposition related to marine air masses, thus highlighting the contribution of terrestrial/anthropogenic sources.  相似文献   

10.
A biomonitoring of airborne trace elements was performed in 2006 in Naples urban area through the exposure of devitalised Hypnum cupressiforme for 10 weeks at 4 m height. In one street, the moss was exposed at different heights to assess vertical gradients of element concentrations. Results were compared with those of a 1999 biosurvey. Correlations among Al, Fe and Ti suggested a soil particles contribution to element uptake. Cu, Mo and Fe were related with traffic flows. Long-range transport contributed to Cd, Cu and Mo accumulation in moss at higher heights. As in 1999, the airborne element load was higher in coastal sites, more affected by marine aerosols and traffic. In all sites, contents of Cd, Fe, Pb, Ni and V in moss were remarkably lower than in 1999, indicating a positive effect of actions set up in recent years to reduce the traffic and to improve the city air quality.  相似文献   

11.
Air quality data obtained at the Jerusalem municipal air monitoring station, during the years 1979–1983, was analyzed to determine seasonal and long-term trends in air quality. The results of this study provide further support to previous findings indicating that ambient air quality levels in Jerusalem are influenced not only by local sources but also by transport of air pollution from Israel's coastal area.The annual and monthly averages of most pollutants indicated that in 1981 record high levels of pollutants were measured. Since total suspended paniculate (TSP) level also peaked in 1981, and since TSP is mostly associated with natural sources, it was concluded that air pollutant levels in the city are influenced more by multiannual change in dispersion conditions than by the combination of all local anthropogenic sources.  相似文献   

12.
Asia is one of the major sources of not only mineral dust but also anthropogenic aerosols. Continental air masses associated with the East Asian winter monsoon always contain high contents of mineral dust and anthropogenic species and transported southeastward to Taiwan, which have significant influences on global atmospheric radiation transfer directly by scattering and absorbing solar radiation in each spring. However, few measurements for the long-range transported aerosol and its optical properties were announced in this area, between the Western Pacific and the southeastern coast of Mainland China. The overall objective of this work is to quantify the optical characteristics of different aerosol types in the Eastern Asian. In order to achieve this objective, meteorological parameters, concentrations of PM10 and its soluble species, and optical property of atmospheric scattering coefficients were measured continuously with 1 h time-resolved from 11 February to 7 April 2004 in Taipei Basin (25°00′N, 121°32′E). In this work, the dramatic changes of meteorological parameters such as temperature and winds were used to determine the influenced period of each air mass. Continental, strong continental, marine, and stagnant air masses defined by the back-trajectory analysis and local meteorology were further characterized as long-range transport pollution, dust, clean marine, and local pollution aerosols, respectively, according to the diagnostic ratios. The aerosol mass scattering efficiency of continental pollution, dust, clean marine, and local pollution aerosols were ranged from 1.3 to 1.6, 0.7 to 1.0, 1.4 and 1.4 to 2.3 m2 g−1, respectively. Overall, there are two distinct populations of aerosol mass scattering efficiencies, one for an aerosol chemical composition dominated by dust (<1.0 m2 g−1) and the other for an aerosol chemical composition dominated by anthropogenic pollutants (1.3–2.3 m2 g−1), which were similar to the previous measurements with high degree of temporal resolution.  相似文献   

13.
This paper provides the first quantitative information on mercury in soil, coastal sediment, and in characteristic organisms of terrestrial and shallow coastal marine ecosystems from Admiralty Bay (King George Island, Antarctica). As expected for a remote area, mercury content is low in abiotic components of the ecosystem, and probably similar to natural levels. Mercury also occurs in very low concentrations in the vegetation, invertebrates and fish. These low mercury levels may be due to sulphide formation in reducing sediments of this environment. Higher concentrations of mercury occurred in bird feathers and mammal hair, indicating biomagnification. This was not found for Zinc. These results may be useful as a reference background to detect future inputs of trace elements in this remote area of the earth. Terrestrial vegetation and bird feathers are suggested as target regional biomonitors.  相似文献   

14.

Coastal areas are frequently influenced by direct and/or indirect multiple anthropogenic pressures, which impacts marine life. Those perturbations may act in a heterogeneous way with a different intensity and are related to the complexity of coastal ecosystems. To visualize all these interactions at a local scale, a methodology inspired from many researches has been implemented in order to search, identify, and classify coastal ecosystems according to their sensitivity to anthropic pressure exerted by coastal cities. Thus, producing vulnerability maps will be essential tools to local coastal managers. We have applied this methodology on five coastal municipalities in Algiers. Firstly, the environmental sensitivity of coastal ecosystems was assessed by analyzing these four sub-indices: biological sensitivity, geomorphological sensitivity, hydrodynamic characteristics, and pollution intensity. Secondly, an assessment of the anthropogenic pressures presented by each municipality was carried out. Five sub-indexes have been taken into consideration when conducting this assessment: human activities, infrastructures, vectors of pollution, urbanization, and regulatory protection. Then, vulnerability maps were produced by the overlapping of sensitivity and anthropic pressure maps. The results assessed for the environmental vulnerability indicated that most areas are moderately to highly vulnerable, especially in the municipalities of Bab El Oued, Rais Hamidou, and Ain Bénian. The analysis of the obtained results shows the potential applicability of this methodology because they accurately reflect the reality. Therefore, these results can be useful to decision-makers by providing them with a relatively rational decision-making tool to prioritize future management and planning efforts.

  相似文献   

15.
Contents of Cd and Zn in the blue mussel, Mytilus edulis, collected on the coast of the southern Bothnian Sea and the northern Baltic proper, were determined using flame AAS. The observed concentrations ranged from 4.7 to 10.8 mg kg(-1) dw for Cd and from 121 to 215 mg kg(-1) dw for Zn. The Zn/Cd ratio was around 20 at a majority of the investigated locations. Cd exhibited an approximate two-fold gradual increase from south to north in the study area. It is likely that this increase was due largely to enhanced bioavailability for Cd at lower salinity. However, it is not possible to eliminate the influence from a generally elevated overall concentration of cadmium in the southern Bothnian Sea caused by natural and anthropogenic input. Compared to mussels from marine waters on the west coast of Sweden, Cd concentrations were 5-10 times higher, similarity indicating an influence of low salinity. Zn did not show these salinity correlated differences. The high Zn content found south of the outlet of the river Dal?lven and gradually decreasing southwards was possibly caused by the high riverine input.  相似文献   

16.
There is still a long-term debate concerning the relative contributions of naturally emitted and anthropogenic Se at the regional and local scales. Here, Se and heavy metal concentrations are reported for epiphytic lichens collected in coastal and inland areas from the USA, Canada and France for assessing atmospheric Se source. Correlations found between Se and Cl in lichens confirmed the major marine biogenic source for atmospheric Se. Continental samples do not show systematic relationships between Se and other metal (Pb, Cu, In …) contents, even for lichens collected in the vicinity of smelters or close to urban areas. Our results suggest that, although anthropogenic Se may be present, the marine biogenic Se source is a major contributor to atmospheric Se for our sampling locations. The contribution of naturally emitted atmospheric Se may be significant in urban and industrial areas and should be taken into account for further studies.  相似文献   

17.
The Persian Gulf is a semi-enclosed marine system surrounded by eight countries, many of which are experiencing substantial development. It is also a major center for the oil industry. The increasing array of anthropogenic disturbances may have substantial negative impacts on marine ecosystems, but this has received little attention until recently. We review the available literature on the Gulfs marine environment and detail our recent experience in the United Arab Emirates (U.A.E.) to evaluate the role of anthropogenic disturbance in this marine ecosystem. Extensive coastal development may now be the single most important anthropogenic stressor. We offer suggestions for how to build awareness of environmental risks of current practices, enhance regional capacity for coastal management, and build cooperative management of this important, shared marine system. An excellent opportunity exists for one or more of the bordering countries to initiate a bold and effective, long-term, international collaboration in environmental management for the Gulf.  相似文献   

18.
For many years, the planning and management of terrestrial areas has been supported by a detailed knowledge of the distribution of habitats and their associated species. However, the detailed mapping of biological resources in extent coastal areas, such as the Norwegian coastal zone, is unrealistic due to its enormous coastline. Here, we present a useful and feasible approach and a set of simple, cost-effective methods which are suitable for providing a broad-scale overview of marine habitats and fish resources. This approach was developed in conjunction with a pioneer study conducted along the southern coast of the Skagerrak, where we combined knowledge gathered from local fishermen with scientific knowledge of important species and nature types to establish a coastal sea mapping program. GIS modeling tools were used in both the mapping program and to integrate local and scientific knowledge into digital maps made available to local area management. This multi-faceted approach, which combines local knowledge and scientific methods, provides valuable information with respect to marine biodiversity, and has been used extensively by local environmental management.  相似文献   

19.
Lake Van in Turkey is the world's largest soda lake (607 km(3)). The lake's catchment area is estimated to be ~12,500 km(2), and the terrestrial input is carried through eolian, riverine, snowmelt and anthropogenic paths. Extent and seasonality of the terrestrial inputs to the lake have not been studied, but it is essential to evaluate its environmental status and to assess the use of environmental proxies to estimate the lake's response to climate changes. This study aims to measure seasonal changes in terrestrial input of natural and anthropogenic origin as recorded by the fluxes of pollen and biomarkers of soil bacteria and vascular or higher plants, as well as petrogenic biomarkers in monthly resolved sediment traps from August 2006 to July 2007. Fluxes of pollen, soil and higher plant biomarkers seem to be related to precipitation and snowmelt in autumn and spring. In addition, dust storms, which are common during the summer months, may have resulted in long-distance transport. Anthropogenic biomarker fluxes indicate year-round petrogenic contamination although some mature biomarker fluxes are higher in summer and in late winter-spring. The relative changes between petrogenic markers indicate variations in the pollutant sources.  相似文献   

20.
Aerosols from urbanized areas of the western United States and Nigeria, as well as from rural air basins with elevated vehicular traffic, contain extractable organic matter composed mainly of petroleum residues, with subordinate waxes from vascular plants and minor polynuclear aromatic hydrocarbons. Petroleum residues can be distinguished from the natural background by their unique compound distributions and molecular marker signatures. The predominant source of the atmospheric petroleum residues is from vehicular exhaust in the form of lubricants. A minor component of PAH is found in aerosols receiving an input of smoke from wood combustion. These anthropogenic constituents are a significant part of urban aerosols and their molecular signature may prove of utility as tracers for air parcels from particular geographic regions and as specific tags for vehicular (especially diesel) emissions.  相似文献   

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