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161.
The impact of industrial heavy metal pollution on Scots pine (Pinus sylvestris L.) and black pine (Pinus nigra Arn.) populations was investigated. Sampled pine stands, which were located in Upper Silesia (southern Poland) in an area strongly polluted by heavy metals, consisted of resistant and sensitive trees. To evaluate the adaptation process, genetic structure and diversity was tested using isozyme analysis. Higher levels of Zn, Pb, Cd and Cu were detected in needles of sensitive trees compared with resistant ones. With respect to morphology, Scots pines were more distinctly impaired than black pines. Although black pines had lower heavy metal concentrations, levels in 1-year-old needles, other than Cu, significantly exceeded “reference plant” values (Markert 1994). In both species, resistant trees demonstrated a lower degree of genetic variation than metal-sensitive trees with respect to some enzyme loci (SHDH A, PGI, PGM, MDH C and DIA). This observation was corroborated in sensitive trees by the smaller number of identified alleles and alleles per locus, absence of private alleles and significant excess of homozygotes in relation to expected Hardy–Weinberg equilibrium values. Assuming that only resistant trees of both species survive under conditions of prolonged soil contamination, the observed genetic structure implies that remaining populations will be depleted of some alleles of unknown adaptive value to future selection pressures. Genetic changes induced by heavy metals suggest an important role for specific enzymes—FEST, SHDH A and B, GOT B and PGI—in the adaptation process. Our results may serve as a basis for selection and propagation of individuals appropriate for re-cultivation of areas chemically degraded by industrial activity.  相似文献   
162.
The aim of this work was the evaluation of QuEChERS extraction method for polycyclic aromatic hydrocarbon (PAH) determination in various types of tea. In the experiment, different kinds of extraction solvents, sorbents and a final method of sample preparation were compared. The final extracts were analysed by gas chromatography-selected ion monitoring-mass spectrometry. The results suggest that acetonitrile extraction, clean up with SAX and final liquid–liquid extraction was the best combination giving the most purified extracts and acceptable compound recoveries for different types of teas. In the study of real samples, compounds belonging to light PAHs were mostly detected, and heavy polycyclic aromatic hydrocarbons, including benzo[a]pyrene, were not identified in any of samples.  相似文献   
163.
The study was aimed to evaluate the selected improvements of nature restoration in a depleted gravel pit. The study site consisted of four water reservoirs of different shapes and sizes, flooded after the gravel extraction ended. Ecological succession monitoring, conducted by the Warsaw University of Life Sciences students associated in the Student Scientific Association of Animal Sciences Faculty since the completion of mining, have focused on amphibians. A twofold approach upheld amphibian species population dynamics, as well as selected habitat elements. The restoration practices dedicated to habitat conditions enhancing have been proved to be definitely effective and useful for similar sites.  相似文献   
164.
The purpose of the research conducted was to investigate and evaluate the behavior of pyrimethanil, pyraclostrobin, boscalid, cypermethrin and chlorpyrifos, the active ingredients of selected fungicides and insecticides, on ripe fruit and in fully developed leaves of raspberry of the Laszka variety. The field trial was carried out in the period of one month starting from the first fruit picking. The results obtained indicated that residue levels on the day of the first crop picking did not even approximate the corresponding EU-MRLs (http://ec.europa.eu/sanco_pesticides). Individual substances in raspberry fruits and leaves disappeared at a similar rate. As a result of chlorpyrifos application to the soil, its residue in fruits and leaves occurred for the whole period of fruit bearing, though in fruit they dropped successively. To produce raspberries with residues below or equal to 0.01 μg g?1, the application of pesticides should be stopped at least 2–3 weeks before the first crop picking, and on condition that an appropriate preparation (active in low doses) is applied to the last treatments.  相似文献   
165.
Gusiatin ZM  Klimiuk E 《Chemosphere》2012,86(4):383-391
The influence of multiple saponin washing on copper, cadmium and zinc removal and stability in three types of soils (loamy sand, loam, silty clay) was investigated. Distribution of metals and their mobility measured as the ratio of exchangeable form to the sum of all fractions in soils was differential. After single washing the highest efficiency of metal removal was obtained in loamy sand (82-90%) and loam (67-88%), whereas the lowest in silty clay (39-62%). In loamy sand and loam metals had higher mobility factors (44-61% Cu, 60-76% Cd, and 68-84% Zn) compared to silty clay (9% Cu, 28% Cd and 36% Zn). Triplicate washing led to increase both efficiency of metal removal and percentage content of their stable forms.In consequence, fractional patterns for metals before and after treatment changed visibly as a result of their redistribution. Based on the redistribution index, the most stable metal (mainly in residual and organic fractions) after triplicate washing was Cu in loamy sand and loam. For silty clay contaminated with Cd, effective metal removal and its stabilization required a higher number of washings.  相似文献   
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