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381.
Changes in DNA sequences affecting cryptic intraspecific variability are very important mechanisms of plant microevolutionary processes, initiating species diversification. In polluted environments, intra- and interpopulation changes at the molecular level proceed rapidly and lead to the formation of new ecotypes in a relatively short time. We used ISSR PCR fingerprinting data to analyze the genetic diversity and genetic structure of seven populations of Viola tricolor: four growing on soil contaminated with heavy metals (Zn, Pb, Cd; waste heaps) and three from control soil. The populations from the polluted sites showed higher genetic polymorphism (%(poly)=84%) and gene diversity (H(T)=0.1709) than the control populations (%(poly)=75% and H(T)=0.1448). The number of private markers we detected within metallicolous (MET) populations was more than double that found within non-metallicolous (NON) populations (15 vs. 7). The STRUCTURE and UPGMA analyses showed clear genetic differences between the NON and MET populations. Based on broad analyses of the genetic parameters, we conclude that the effect of these polluted environments on the genetic diversity of the MET populations, separating them from the NON populations, is evidence of microevolutionary processes at species level, leading to species divergence and the emergence of local ecotypes better adapted to their different environments.  相似文献   
382.
This paper provides data on baseline concentrations, interrelationships and bioconcentration potential of 12 metallic elements by King Bolete collected from 11 spatially distant sites across Poland. There are significant differences in concentrations of metals (Al, Ba, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Sr, Zn) and their bioconcentration potential in King Bolete Boletus edulis at 11 spatially distant sites surveyed across Poland. These have resulted from significant geographical differences in trace metal concentrations in a layer (0-10 cm) of organic and mineral soil underneath to fruiting bodies and possible local bioavailabilities of macro- (Ca, K, Mg, Na) and trace metals (Al, Ba, Cd, Cu, Fe, Mn, Sr, Zn) to King Bolete. The use of highly appreciated wild-grown edible King Bolete mushroom has established a baseline measure of regional minerals status, heavy metals pollution and assessment of intake rates for wild mushroom dish fanciers against which future changes can be compared. Data on Cd, Cu and Zn from this study and from literature search can be useful to set the maximum limit of these metals in King Bolete collected from uncontaminated (background) areas. In this report also reviewed are data on Al, Ba, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Sr and Zn accumulation in King Bolete.  相似文献   
383.
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   
384.
Environmental Science and Pollution Research - In this study, wastewater from municipal services, such as a port wastewater reception facility (PRF-WW) and a municipal solid waste plant (MSWP), was...  相似文献   
385.

Due to its adverse impact on health, as well as its global distribution, long atmospheric lifetime and propensity for deposition in the aquatic environment and in living tissue, the US Environmental Protection Agency (US EPA) has classified mercury and its compounds as a severe air quality threat. Such widespread presence of mercury in the environment originates from both natural and anthropogenic sources. Global anthropogenic emission of mercury is evaluated at 2000 Mg year−1. According to the National Centre for Emissions Management (Pol. KOBiZE) report for 2014, Polish annual mercury emissions amount to approximately 10 Mg. Over 90% of mercury emissions in Poland originate from combustion of coal.

The purpose of this paper was to understand mercury behaviour during sub-bituminous coal and lignite combustion for flue gas purification in terms of reduction of emissions by active methods. The average mercury content in Polish sub-bituminous coal and lignite was 103.7 and 443.5 μg kg−1. The concentration of mercury in flue gases emitted into the atmosphere was 5.3 μg m−3 for sub-bituminous coal and 17.5 μg m−3 for lignite. The study analysed six low-cost sorbents with the average achieved efficiency of mercury removal from 30.6 to 92.9% for sub-bituminous coal and 22.8 to 80.3% for lignite combustion. Also, the effect of coke dust grain size was examined for mercury sorptive properties. The fine fraction of coke dust (CD) adsorbed within 243–277 μg Hg kg−1, while the largest fraction at only 95 μg Hg kg−1. The CD fraction < 0.063 mm removed almost 92% of mercury during coal combustion, so the concentration of mercury in flue gas decreased from 5.3 to 0.4 μg Hg m−3. The same fraction of CD had removed 93% of mercury from lignite flue gas by reducing the concentration of mercury in the flow from 17.6 to 1.2 μg Hg m−3. The publication also presents the impact of photochemical oxidation of mercury on the effectiveness of Hg vapour removal during combustion of lignite. After physical oxidation of Hg in the flue gas, its effectiveness has increased twofold.

  相似文献   
386.
Salvia officinalis L. is a popular herb widely used in culinary, cosmetic, and medicinal preparations, and also as an ornamental plant. Sage crops are threatened by many diseases, such as gray mold, powdery mildew, and leaf spot, by weeds, and by pests, such as aphids. Use of crop protection products may lead to presence of pesticide residues in this herb. The aim of this work was to study presence of pesticide residues in the herb, S. officinalis L., available on the retail market in Poland, to verify their compliance with the maximum residue levels (MRLs) and to assess the chronic and acute risks associated with consumption of this herb and infusions prepared from contaminated sage plants. Ninety active substances of pesticides were analyzed, including all active substances registered in Poland for protection of the sage. Five active substances were found, one fungicide – boscalid and four insecticides: chlorpyrifos, pp′-DDT, dimethoate (residue levels above MRL) and indoxacarb. The chronic and acute exposure to pesticide residues consumed with sage did not exceed 0.02% of the acceptable daily intake (ADI) and 0.1% of the acute reference dose (ARfD), respectively.  相似文献   
387.
Heavy metals, including cadmium (Cd), lead (Pb) and mercury (Hg) act as nephrotoxic agents, particularly in the renal cortex. The aim of the study was to determine the concentrations of Cd, Pb and Hg in kidneys removed from patients due to lesions of various etiologies and from patients after the rejection of transplanted kidneys. Additionally, we determined the influence of selected biological and environmental factors on the concentrations of toxic metals. The study material consisted of kidneys with tumor lesions (n = 27), without tumors (n = 7) and its extracted grafts (n = 10) obtained from patients belongs to the north-western areas of Poland. The determined metal concentrations in the renal cortex and medulla may be arranged in the following descending order: Cd > Pb > Hg. The highest concentrations of Cd and Hg were found in the cortex, while the maximum content Pb was observed in the medulla. Significant correlations were found in the concentrations of the same metals between cortex and medulla and between Pb and Hg in the renal medulla. Pb content was higher in the renal medulla of men than in the cortex of the elderly (above 60 years of age). The highest concentrations of Pb and Hg were found in the cortex and medulla, of the kidneys had not neoplastic changes, and lower content of these metals were found in the extracted kidney grafts. In summary, renal grafts accumulate less heavy metals than cancerous kidneys, what could have been caused by immunosuppressors taken by the graft recipients. Moreover, sex, age and smoking are key factors responsible for xenobiotics concentrations.  相似文献   
388.
The aim of this study was to assess the effect of infection with Fusarium fungi and chemical protection on the contents of phenolic acids and antioxidative potential of extracts from grains of 23 wheat genotypes. Based on chemical analyses including abiotic factors such as weather conditions and the location of the plantation, the authors attempted to clarify non-enzymatic antioxidative response mechanisms to two different stressors in 23 wheat genotypes. Based on chemical analysis, it was found that mass infection with fungi from the genus Fusarium induces defence mechanisms of the plant, which results in an increased production of phenolic acids, mainly those, which are substrates for the production of acids exhibiting antimicrobial action. This mechanism is confirmed by the analyses of antioxidant activity, which also increases significantly during fungal infection, connected with the production of mycotoxins. In the course of chemical plant protection, significant changes were observed in the production of phenolic acids. Even if antioxidant activity was not higher in comparison to the control, an increased production of certain phenolic acids was recorded, which suggests stimulation of the resistance system of the plant, at a simultaneous complete response of antioxidative mechanisms, as it takes place during fungal infection.  相似文献   
389.
The leaves of eight Salix species/hybrids were collected from two sites with different soil conditions including metal concentrations to investigate the concentration of Cu, Zn and Pb, phenolic profile and antioxidant scavenging activity. Cu, Zn and Pb, phenolic content and scavenging activity in leaves from the control area (lower concentration of metals in soil) (site C) were lower than in plants cultivated in site G (higher concentration of metals in soil). The content of Cu, Pb and Zn in leaves was in the range 9.21 (site G)–52.36 (site G), 0.41 (site C)?12.03 (site C) and 27.23 (site C)–214.44 (site G) mg?kg?1, respectively. Total phenolic content ranged between 18.19 (site C) and 84.71 (site G) mg gallic acid equivalent per gram of dry matter. Total flavonoid content was between 7.98 (site C) and 54.48 (site G) mg catechin g?1?d.m. The scavenging effect on 2,2-diphenyl-1-picrylhydrazyl˙ ranged between 33.6% (site C) and 56.3% (site G). Phenolic acids, myricetin and quercetin were quantified in leaves. The results show that phenolics are involved during adaptive mechanisms under elevated content of Cu, Pb and Zn in soil. Changes in the phenolic composition in leaves can be suggested as indicators of metal stress in Salix plants.  相似文献   
390.
In contaminated soils, excessive concentrations of metals and their high mobility pose a serious environmental risk. A suitable soil amendment can minimize the negative effect of metals in soil. This study investigated the effect of different biochars on metal (Cu, Pb, Zn) immobilization in industrial soil. Biochars produced at 300 and 600 °C from conventional (MS, maize silage; WP, wooden pellets) and alternative (SC, sewage sludge compost; DR, digestate residue) feedstocks were used as soil amendments at a dosage of 10 % (w/w). The type of feedstock and pyrolysis temperature affected the properties of the biochars and their ability to immobilize metal in soil. Compared to production at 300 °C, all biochars produced at 600 °C had higher pH (6.2–10.7), content of ash (7.2–69.0 %) and fixed carbon (21.1–56.7 %), but lower content of volatile matter (9.7–37.2 %). All biochars except DR biochar had lower dissolved organic carbon (DOC) content (1.4–2.3 g C/L) when made at 600 °C. Only MS and SC biochars had higher cation exchange capacity (25.2 and 44.7 cmol/kg, respectively) after charring at 600 °C. All biochars contained low concentrations of Cd, Cu, Ni, Pb and Zn; Cd was volatilized to the greatest extent during pyrolysis. Based on FTIR analysis and molar ratios of H/C and O/C, biochars had a greater degree of carbonization and aromaticity after charring at 600 °C. The efficiency of the biochars in metal immobilization depended mainly on their pH, ash content, and concentration of DOC. SC and DR biochars were more effective for Cu and Zn immobilization than MS and WP biochars, which makes them attractive options for large-scale soil amendment.  相似文献   
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