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21.
The objective of this study was to identify Z. indianus in PEJC and PESCAN. Listed are the following methods: to isolate bacteria from the integument of the Z. indianus species collected and to check the resistance of microorganisms to antibiotics. Collections of Z. indianus were performed in four seasons of the two parks. The results obtained suggest that the low amount of Z. indianus collected can be justified by environmental factors such as high average temperature and low average humidity. It is noted that there is a predominance of bacteria of the Enterobacteriaceae family found in both the PEJC and the PESCAN. The antibiogram performed for the isolated PEJC bacteria shows statistical significance when comparing the edge and inside values of the park. Studies with fungi were also carried out, and it was evidenced that Trichophyton spp. was the genus that most inhabited the two environments studied. The ability of fluconazole and ketoconazole to inhibit fungal growth was also investigated, and considering the concentration tested may suggest that they have good action spectra. Plasmid profile data show that 60% of antibiotic-resistant bacteria have plasmids. The values found show that Z. indianus can act as vectors of microorganisms that affect the healthy animals and humans and that these organisms may be influenced by seasons.  相似文献   
22.
The adaptive significance of multiple matings for females is a matter of much controversy. In insects, supplying the female’s sperm reserves with portions of fresh spermatozoa may be the main function of multiple matings. This simple explanation may also be applied to other animals which produce large numbers of eggs over prolonged periods of time. We tested the fertility insurance hypothesis in Montandon’s newt (Triturus montandoni, Amphibia, Salamandridae). T. montandoni females are inseminated internally by spermatophores they have picked up, and subsequently lay eggs fertilized by spermatozoa released from the spermatheca. We compared the reproductive success of singly and multiply inseminated females of Montandon’s newt in the laboratory. Multiply inseminated females laid more eggs and had a lower percentage of non-developing eggs than females who mated only once. Our data suggest that remating increases the reproductive success of multiply inseminated females by replenishing sperm reserves in the spermatheca or by supplying females with fresh portions of spermatozoa with high fertilizing capacity. Received: 7 January 2000 / Revised: 13 September 2000 / Accepted: 7 October 2000  相似文献   
23.
Protected areas due to their long-term protection are expected to be characterized by good water quality. However, in catchments where arable fields dominate, the impact of agriculture on water pollution is still problematic. In Poland, recently, the fertilization level has decreased, mostly for economic reasons. However, this applies primarily to phosphorus and potassium. In order to evaluate the impact of agriculture on water quality in a protected area with a high proportion of arable fields in the aspect of level and type of fertilization, complex monitoring has been applied. The present study was carried out in Wielkopolska National Park and its buffer zone, which are protected under Natura 2000 as Special Areas of Conservation and Special Protection Areas. The aim of the study were (1) to assess the impact of agriculture, with special attention on fertilization, on groundwater, and running water quality and (2) to designate priority areas for implementing nitrogen reduction measures in special attention on protected areas. In our study, high nitrogen concentrations in groundwater and surface waters were detected in the agricultural catchments. The results demonstrate that in the watersheds dominated by arable fields, high nitrogen concentrations in groundwater were measured in comparison to forestry catchments, where high ammonium concentrations were observed. The highest nitrogen concentrations were noted in spring after winter freezing, with a small cover of vegetation, and in the areas with a high level of nitrogen application. In the studied areas, both in the park and its buffer zone, unfavorable N:P and N:K ratios in supplied nutrients were detected. Severe shortage of phosphorus and potassium in applied fertilizers is one of the major factors causing leaching of nitrogen due to limited possibilities of its consumption by plants.  相似文献   
24.
Polychlorinated dibenzothiophenes (PCDTs) could be classified as persistent organic pollutants (POPs) in the environment and are particularly interesting due to their structural resemblance to highly toxic dioxins. We show here some basic environmental properties such as n-octanol water (KOW), n-octanol/air (KOA) and air/water (KAW) partition coefficients as well as Henry’s law constants (KH) for all 135 congeners of chlorodibenzothiophene. Predictions were made by regression of principal components (PCR) and with aid of a set of standard chemicals, for which physical–chemical properties are well featured. Computed KOW, KOA, KAW and KH values for mono-CDTs ranged, respectively, between 4.66 and 4.71, 7.48 and 7.55, −2.84 and −2.82, 3.56 and 3.74; for di-CDTs between 5.02 and 5.28, 8.03 and 8.29, −3.01 and −2.95, 2.42 and 2.75; for tri-CDTs between 5.53 and 5.70, 8.65 and 8.87, −3.2 and −3.11, 1.58 and 1.92; for tetra-CDTs between 5.95 and 6.13, 9.27 and 9.50, −3.39 and −3.27, 1.02 and 1.33; for penta-CDTs between 6.38 and 6.51, 9.88 and 10.05, −3.54 and −3.45, 0.72 and 0.88; for hexa-CDTs between 6.83 and 6.97, 10.54 and 10.66, −3.72 and −3.64, 0.47 and 0.56; for hepta-CDTs between 7.28 and 7.35, 11.12 and 11.20, −3.81 and −3.87, 0.33 and 0.38; for octa-CDT 7.74, 11.78, −4.04 and 0.23. An estimated value of the three types of partition coefficient and Henry’s law constants suggest that polychlorinated dibenzothiophenes are lipophilic and semi-volatile persistent organic pollutants. Their mobility in the environment seems to be very similar to that of some well-known POPs such as polychlorinated dibenzofurans, -dibenzo-p-dioxins, and -biphenyls or organochlorine pesticides.  相似文献   
25.
26.
The goal of this paper is to assess the current status and trends of total mercury (THg) contamination of the atmosphere and terrestrial ecosystems in Poland. The study shows that the reduced domestic and worldwide atmospheric emission of Hg resulted in decreased THg level in the terrestrial biotope and biosphere. Considering that Poland is one of the main Hg emitters in Europe, the THg concentrations in its abiotic environment are still elevated. However, the THg level in terrestrial organisms is relatively low, which is because a large proportion of Hg deposited on land is accumulated in organic-rich soils. Regarding the THg concentration, consumption of wildlife and livestock from Poland is safe for humans. Nevertheless, the authors indicate the need for effective environmental monitoring, based on selected bioindicators, which is crucial considering the slowing reduction of Hg emission combined with the consequences of the changing climate.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01505-1.  相似文献   
27.
The doubly uniparental system of mitochondrial inheritance (DUI) is best known in marine mussels Mytilus. Under DUI there are two types of mitochondrial DNA (mtDNA). The female type (F) is transmitted to offspring of both genders and the male type (M) exclusively to sons; consequently two distinct mtDNA lineages exist. The M lineage evolves under more relaxed selection than the F lineage resulting in higher polymorphism within the M lineage. Though this polymorphism is expected to make inferences on fine population structure easier using M instead of F data, no comprehensive comparative data exist to support this claim. We sequenced a 1,205 bp fragment of M and F mtDNA comprising parts of the COIII and ND2 genes, and analysed 204 individuals representing three Mytilus species: M. edulis, M. galloprovincialis and M. trossulus from 13 European sampling sites. A clear distinction between Mediterranean and Atlantic populations was found with both M and F data, but much better geographic differentiation was found within the Atlantic using F rather than M data. In particular, Atlantic M. galloprovincialis can be differentiated from Atlantic M. edulis, and further subdivision of Atlantic M. edulis is possible using the F data but not the M data. Multiple tests of selection were carried out to attempt to explain this paradox. We concluded that the overall pattern of polymorphism is consistent with strong purifying selection; not only is this selection relaxed in the M lineage in comparison with the F lineage, but it is also more frequently interrupted by periodic selective sweeps within the M lineage.  相似文献   
28.
This report shows an unexpected toxicity decrease during atrazine photoelectrodegradation in the presence of NaCl. Atrazine is a pesticide classified as endocrine disruptor occurring in industrial effluents and agricultural wastewaters. We therefore studied the effects of the degradation method, electrochemical and electrochemical photo-assisted, and of the supporting electrolyte, NaCl and Na2SO4, on the residual toxicity of treated atrazine solutions. We also studied the toxicity of treated atrazine solutions using Artemia nauplii. Results show that at initial concentration of 20 mg L−1, atrazine was completely removed in up to 30 min using 10 mA cm−2 electrolysis in NaCl medium, regardless of the electrochemical method used. The total organic carbon removal by the photo-assisted method was 82% with NaCl and 95% with Na2SO4. The solution toxicity increased during sole electrochemical treatment in NaCl, as expected. However, the toxicity unexpectedly decreased using the photo-assisted method. This finding is a major discovery because electrochemical treatment with NaCl usually leads to the formation of toxic chlorine-containing organic degradation by-products.  相似文献   
29.
Primary objectives of our work were to spatially delineate post industrial areas of the EU-27 and indicate key environmental, social and economic sensitivity issues for these regions. The density of industrial sites within NUTS-x regions for EU-27 countries was assessed by using CORINE 2000 land cover layer. A development of postindustrial society in Europe represents a strong geographic diversity. There are distinct historical and current differences between regions which form major groups, comprising similar internal characteristics and definable trends in environmental and socioeconomic sense. Regions grouped into postindustrial clusters are fundamentally different from the European average, and are facing specific problems related to global market and political changes. Eastern postindustrial regions can be characterized as socially and economically weak, exhibiting high unemployment rate, low GDP, negative population growth and a strong environmental pressure, represented by a high density of dump sites. Most of the western EU postindustrial areas have been successfully recovered and moved into new economy as shown by most of the indicators. In urban postindustrial zones, however, emission sources of pollutants seem to continually be a major problem--not necessarily in terms of exceeding thresholds, but through a remarkable difference in the amount of pollutants produced relative to other regions.  相似文献   
30.
Granstedt A 《Ambio》2002,31(6):496-7; discussion 497-8
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