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101.
102.
The village with its characteristic zones of different land use from the center to the periphery is a basic unit of Europe's cultural landscapes. However, loss of the authentic pre-industrial village structure characterized by a fine-grained structure of arable land and wooded grasslands is a threat to both cultural heritage and biodiversity in many rural landscapes. Therefore, it is important that the extent and rate of change of such authentic villages in a landscape can be monitored. We studied to what extent loss of authenticity with increasing time after abandonment can be assessed by quantitative analysis and visual interpretation of satellite images. The study was carried out in the Bieszczady Mountains, SE Poland in 1999. Using Landsat Thematic Mapper data from 1998, both the grain size of landscape elements (size of fields) and land-cover composition (encroachment of shrub and forest) were quantitatively described 6 type villages representing different stages of deterioration of the authentic village structure. Historical maps were used to delineate the border of the villages and the former extension of forest and open land was measured. The present land use and the degree of abandonment expressed as grain size and forest encroachment were mapped using satellite data. Deterioration occurred along 2 transformation paths: abandonment and ultimately becoming forest, or intensified agriculture, respectively. To validate these results we classified 22 other villages in a 1000 km2 area by visual interpretation of the original satellite images into 1 of 4 types. We then collected historical data on human population changes over the past six decades. The classification of village authenticity was clearly related to the rate of human population decline. We address the importance of validating and applying this approach for rapid assessment of the authenticity of cultural landscapes in European regions being subject to ongoing as well as expected future change, related to expansion of the European Union. Finally, we argue that the village represents a scale at which integration of natural and social sciences is possible.  相似文献   
103.
The leachability of heavy metals such as chromium (Cr), lead (Pb) and cadmium (Cd) from the ash material obtained from waste combustion was studied. The effects of ash surface topography and morphology on the leachability of these elements were examined using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The AFM (scan size 10 x 10 microns) and SEM images of the simulated ash pellet obtained at various operating temperatures (1000, 1400 and 1500 degrees C) showed significant microstructural and topographical changes. Ash pellets treated at 1000 degrees C contain porous and non-continuous surface. On the other hand, the ash pellet obtained at higher temperature (1500 degrees C) was found to contain a smooth, continuous and non-porous surface. The AFM height profile studies indicated that the top surface variation of the ash pellet at 1000, 1400 and 1500 degrees C were found to be -40.0 to 25.5, -3.7 to 4.7 and -0.10 to 0.66 nm respectively. The SEM analyses also confirmed the presence of smooth, non-porous outer surface of ash formed at 1500 degrees C. In addition, it also showed the presence of compact and rigid interior for the same ash pellet. The leachability of the heavy metals was determined using standard toxicity characteristic leaching procedure (TCLP) test and the samples were analysed using atomic absorption spectroscopy. The results showed that the TCLP leaching ratios of the heavy metals were Cr = 0.30, Pb = 0.05 and Cd = 0.09 at 1000 degrees C. However, the ash obtained at 1400 degrees C showed negligible heavy metals leaching ratio while at 1500 degrees C no leachability was detected (TCLP concentration dropped to nondetectable levels). The use of high temperature treatment enabled the immobilization of heavy metals in the ash preventing their leaching. Such ash can be considered as a non-hazardous material for reuse or safe disposal.  相似文献   
104.
Levels of tributyltin (TBT) and its degradation products, mono- (MBT) and dibutyltin (DBT), as well as triphenyltin (TPT), were monitored in 10 stations along the Polish coast (Baltic Sea). Mussel-Mytilus edulis-and fish-Platichthys flesus-were used as sentinel organisms. The bioaccumulation patterns of butyltin and phenyltin compounds varied substantially. Butyltins were detected in mussel tissue from all the sampled stations. Among them, organisms from the Gulf of Gdansk showed the highest residues (68 ng/g w.w. as Sn) in conjunction with elevated TBT/DBT ratios, which suggest recent inputs of TBT in the area. Additionally, flatfish were sampled in the Gulf of Gdansk, and different tissues (liver, digestive tube and gills) were analyzed separately. TPT, although undetected in mussels, was always present in fish. The highest organotin concentration was observed in the liver (369 ng/g w.w. as Sn) of fish caught near Gdansk port. Relatively high concentrations were observed in digestive tube, which points out the ingestion of organotin contaminated food as an important uptake route of those compounds in P. flesus.  相似文献   
105.
The mercury compounds introduced to the environment because of anthropogenic activity are accumulated, mainly, in marine sediments. Both distribution of mercury in the Baltic Sea and factors affecting it are remain largely unknown. Due to its complex chemistry and variable conditions in the Baltic Sea bottom sediments, mercury may be reemitted to the overlaying water, and thus to the environment.The aim of this study was twofold. Total mercury contents were measured in sediments of the Gdansk Basin along a Vistula mouth (main source)--Gdansk Deep (deposition area) transect in order to assess spatial distribution of the element. Soft and sandy bottom sediment cores were collected and cut into slices. The mercury measurements consisted of acid digestion followed by CV-AAS determination. A five-step sequential extraction procedure involving measurements of mercury species water soluble, bound to humic substances and insoluble, was employed in order to investigate mercury speciation. On the basis of speciation results stability and remobilisation potential was assessed. The second aim was demonstrating that mercury gradients in vertical profiles of the investigated sediment cores exist.Total mercury contents varied in range from 28 ng/g x dw to 844 ng/g. Mercury associated with organic matter and sulphides, (respectively 39% and 49%) were the dominant species of the element. The results indicated that the river run-off is a source of mercury in the area. Vertical gradients of both total content and speciation of mercury in the soft sediments were attributed to both remobilisation from sediments, and decreasing trend in the anthropogenic load of the element deposited to sediments.  相似文献   
106.
Within the framework of the project "Effects of forest health on biodiversity with emphasis on air pollution in the Carpathian Mountains" 26 permanent study sites were established in the vicinity of the ozone monitoring sites. The study sites were located on the NW-SE transect through the Western (12 sites), Eastern (11 sites) and Southern (3 sites) Carpathians in forest ecosystems typical of each area. Some of the forest monitoring sites were located in national parks, biosphere reserves and areas of protected landscape. Each permanent site of 0.7 ha area consisted of 5 small 500m(2) circular plots, arranged in the form of a cross, i.e. four placed on the cardinal points (N, E, S, W) and one in the center. Phytosociological records were done twice during the 1998 growing season using the Braun-Blanquet's method. The study sites represented various types of forest: Picea abies stands (8), beech (Fagus sylvatica) stands (10), fir (Abies alba) stands (2) and mixed beech-fir, spruce-fir and beech-spruce stands (6). Age of most stands was 80-100 years. Degree of crown damage varied greatly between sites, a percentage of damaged trees decrease in Carpathians from West to East. It corresponds well with the O(3) level in these areas. Typical damage by O(3) in herb layer species in several Carpathian sites were found. Land-use map for the entire Carpathian Mountains and two detailed land use maps for Tatras (Western Carpathians) and Retezat (Southern Carpathians) are presented. A little more than half of the Carpathian territory is forested. The most densely forested are Eastern Carpathians, while the most sparsely Western Carpathians. Arable lands occupy 22.6% of the Carpathians, pastures and meadows 6.2%, water bodies 1.9%, and build up areas several percent. In the highest elevation of the Carpathians alpine meadows (11.3%) and rocks (3.5%) are distributed.  相似文献   
107.
Tadeusz Skowroński 《Chemosphere》1984,13(12):1379-1384
The investigations showed that Stichococcus bacillaris took up cadmium by means of adsorption and energy-dependent transport. Cadmium transport into alga cells was inhibited in the dark as well as under the influence of the uncouplers: 2,4-dinitrophenol (DNP), carbonyl cyanide m-chlorophenylhydrazone (CCCP), and ATPase inhibitor - N, N′ - dicyclohexylcarbodiimide (DCCD). It has also been stated that CCCP caused ATP level decrease in cells.  相似文献   
108.
A global three-dimensional Lagrangian chemistry-transport model STOCHEM is used to describe the European regional acid deposition and ozone air quality impacts along the Atlantic Ocean seaboard of Europe, from the SO2, NOx, VOCs and CO emissions from international shipping under conditions appropriate to the year 2000. Model-derived total sulfur deposition from international shipping reaches over 200 mg S m(-2) yr(-1) over the southwestern approaches to the British Isles and Brittany. The contribution from international shipping to surface ozone concentrations during the summertime, peaks at about 6 ppb over Ireland, Brittany and Portugal. Shipping emissions act as an external influence on acid deposition and ozone air quality within Europe and may require control actions in the future if strict deposition and air quality targets are to be met.  相似文献   
109.
In the experiment reported the results obtained with two different columns for the RP-HPLC analysis of phytoplankton pigment components were compared. LiChroCART Hypersil ODS and LiChroCART LiChrospher 100 RP18e columns were used exchangeably. Two groups of high-purity pigment standards of reference phytoplankton strains (23 chlorophylls and carotenoids in the first case and 25 in the second case) were subjected to chromatographic analysis. All calibration parameters (retention times, calibration curves, spectrum shapes, detection thresholds) for qualitative and quantitative identification of pigments were determined. The results indicate that both columns used in the analysis ensure sufficient resolution and can be used interchangeably for the analysis of pigments present in naturally existing phytoplankton, even when present in only trace amounts.Communicated by O. Kinne, Oldendorf/Luhe  相似文献   
110.
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