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91.
Szopka K  Karczewska A  Kabała C 《Chemosphere》2011,83(11):1507-1512
The study was aimed to examine total concentrations and pools of Hg in surface layers of soils in the Karkonosze Mountains, dependent on soil properties and site locality. Soil samples were collected from a litter layer and the layers 0-10 cm and 10-20 cm, at 68 sites belonging to the net of a monitoring system, in two separate areas, and in three altitudinal zones: below 900 m, 900-1100 m, and over 1100 m. Air-borne pollution was the major source of mercury in soils. Hg has accumulated mainly in the litter (where its concentrations were the highest), and in the layer 0-10 cm. Hg concentrations in all samples were in the range 0.04-0.97 mg kg−1, with mean values 0.38, 0.28, and 0.14 mg kg−1 for litter and the layers 0-10 cm and 10-20 cm, respectively. The highest Hg concentrations in the litter layer were found in the intermediate altitudinal zone, whereas Hg concentrations in the layer 0-10 cm increased with increasing altitude. Soil quality standard for protected areas (0.50 mg kg−1) was exceeded in a few sites. The pools of Hg accumulated in soils were in the range: 0.8-84.8 mg m−2, with a mean value of 16.5 mg m−2, and they correlated strongly with the pools of stored organic matter.  相似文献   
92.
In this work, possible relationships between global DNA methylation and metal/metalloid concentrations in earthworms have been explored. Direct correlation was observed between soil and tissue As, Se, Sb, Zn, Cu, Mn, Ag, Co, Hg, Pb (p < 0.05). Speciation results obtained for As and Hg hint at the capability of earthworms for conversion of inorganic element forms present in soil to methylated species. Inverse correlation was observed between the percentage of methylated DNA cytosines and total tissue As, As + Hg, As + Hg + Se + Sb (β = −0.8456, p = 0.071; β = −0.9406, p = 0.017; β = −0.9526, p = 0.012 respectively), as well as inorganic As + Hg (β = −0.8807, p = 0.049). It was concluded that earthworms would be particularly helpful as bioindicators of elements undergoing in vivo methylation and might also be used to assess the related risk of epigenetic changes in DNA methylation.  相似文献   
93.
Source apportionment of air pollution due to particulate matter with an aerodynamic diameter <10 μm (PM10) was investigated in Central Eastern European urban areas. A combination of four methods was developed to distinguish long-range transport (LRT) and regional transport (RT) from local pollution (LP) sources as well as to discern the involvement of traffic or residential sources in LP. Sources of PM10 events of pollution were determined in January 2006 in representative Polish cities using monitored air quality and meteorological data, backward air mass trajectories, correlation and principal component analysis (PCA). Daily patterns of PM10 levels show that several peak episodes were registered in Poland; January 21–30th being the most polluted days. Air mass back-trajectory analysis shows that all cities were under the influence of LRT from North-eastern origins (Russia–Belarus–Ukraine), most were also under LRT from Southern origin (Slovakia, Czech Republic), and northern cities were under national RT influence. PCA analysis shows that ion-sums of secondary inorganic aerosols account for LRT pollution while arsenic and chromium represents markers of RT (industrial) and LP (residential) sources of PM10, respectively. Determination of several ratios (REG/UB, REG/TRAF, TRAF/UB) calculated between PM10 levels measured at regional background (REG); urban background (UB) and traffic (TRAF) monitoring sites shows that, with ratios REG/UB ≥ 0.57, PM10 episodes in both Szczecin and Warsaw bore a marked RT origin. The lower REG/UB ≤ 0.35 in the Southern cities of Cracow and Zabrze indicates that LP was the main contributor to the observed episodes. Only PM10 episodes in Southern-western Poland (Jelenia Góra) were clearly of LP origin as characterized, by the lowest REG/UB ratio (<0.2). The high TRAF/UB ratios obtained for all cities (close to 1) indicate that there was a great uniformity of PM levels on an urban scale owing to the meteorologically stagnant conditions. A high correlation between PM10, NO2 and CO confirms that traffic emission represented a common and an important LP source of urban pollution in most Polish cities during January 2006. On the other hand PM10 which is also highly correlated with SO2 in 4 cities out of 6, indicates that coal combustion through domestic heating or industrial activities was also an important LP source of PM10. Finally, extremely unfavourable meteorological conditions caused by the influence of a Siberian high-pressure system were found to be associated with the occurrence of severe PM10 episodes of pollution.  相似文献   
94.
Environmental Science and Pollution Research - Birds have been using anthropogenic materials for nest construction for the past few decades. However, there is a trade-off between the use of new...  相似文献   
95.
96.
The protection and regeneration of wetlands has been of crucial importance as a goal in ecological research and in nature conservation for some time and is more important than ever now. Knowledge about the biophysical properties of wetlands' vegetation retrieved from satellite images enables us to improve the monitoring of these unique areas, which are otherwise very often impenetrable and therefore difficult to examine, analyze and assess by means of site visits. The Biebrza Wetlands are situated in the North-East part of Poland and are one of the largest areas made up of marshes and swamps in the entire EU. This is still one of the wildest areas and one of the least destroyed, damaged or changed by human impact. However, in the recent decades there have been attempts made to intensify and overexploit the natural resources of the region and implement new agriculture practices in the area. In this period, drainage canals have been built, and a good deal of the area has been drained. The area of this precious ecosystem covers 25 494 ha. This valuable area of peat with unique vegetation species and with very special birds is one of the most valuable areas in Europe and in 1995 was added to the list of Ramsar sites. The investigation of wetlands in the Biebrza River Valley has been carried out at ground level by taking measurements of soil moisture, evapotranspiration, Leaf Area Index, wet and dry biomass and the levels of ground water and meteorological parameters. Also examined were radiative temperature, detailed vegetation mapping, and APAR. For some years the deterioration of peat lands has been noticed due to the drying out of the area and the frequent outbreak of fires. The consequence is the succession of new vegetation and the appearance of new ecosystems. The Remote Sensing Centre in the Institute of Geodesy and Cartography has undertaken the investigation by applying ERS-2.SAR and ENVISAT ASAR of IS2 and IS4 and VV, HH, HV polarization for the purpose of modeling soil moisture and humidity changes of the area under investigation. The investigation also aimed at finding the best biophysical properties of wetlands' vegetation to characterize marshland habitats and its changes. At the same time as registering the microwave data, the optical data from Landsat ETM+, SPOT VEGETATION, ERS-2.ATSR, ENVISAT MERIS, and NOAA/AVHRR have been registered and information about the biomass and heat fluxes as sensible and latent heat has also been calculated. The vegetation indices are calculated from EO satellite data taking into account jointly the features of vegetation responsible for reflection in various bands and combining this information from several spectral bands. Also, the changes in the humidity of the area have been examined by extracting the backscattering coefficients from two SAR images that were taken at a similar period of the year but with a gap of 5 years. The information about soil moisture as retention, soil moisture changes, heat fluxes and evapotranspiration are all very important for estimates of CO(2) sequestration. The ENVISAT images have been obtained for the ESA AO-ID122 project. Also the SMOS and ALOS data will be applied for the Biebrza Wetlands in the future.  相似文献   
97.
Environmental Science and Pollution Research - This literature review outlines the most important—agricultural and non-agricultural—types of sewage sludge management. The potential of...  相似文献   
98.
99.
Environmental Chemistry Letters - The increasing use of pesticides is a major health issue. There is therefore a need for improved analytical methods and more knowledge on the interaction of...  相似文献   
100.
Environmental Science and Pollution Research - Uzarzewskie Lake was a hypereutrophic, dimictic lake characterized by low water transparency, high chlorophyll-a concentration and intense...  相似文献   
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