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51.
Agnieszka Mościcka-Teske Marcin Butlewski Agnieszka Misztal Aleksandra Jacukowicz 《International journal of occupational safety and ergonomics》2013,19(4):510-518
This article shows the results of research on psychosocial risks for a group of machine and plant operators (n?=?1014) from the construction, chemical, energy, mining, metal and food industries in Poland. The Psychosocial Risk Scale designed in Nofer Institute of Occupational Medicine (NIOM) by Moscicka-Teske and Potocka was used to indicate the occurrence of general and specific occupational stressors and the level of their stressfulness. The results revealed that the studied machine and plant operators experience job context stress – related to working environment features concerning work organization – more frequently than job content stressors – related to the type of tasks they perform. Moreover, a correlation analysis between work features and the health and occupational functioning of the respondents revealed significant but weak relationships between the variables (from ?0.08 to ?0.23). Comparative analysis revealed the differences between the studied sectors. Such a comparison makes it possible to set goals for each sector and to attempt to improve the distinctive areas. 相似文献
52.
Piotr Sikorski Iwona Szumacher Daria Sikorska Marcin Kozak Marek Wierzba 《Environmental monitoring and assessment》2013,185(7):5823-5836
Visitor’s access to understorey vegetation in park forest stands results in the impoverishment of plant species composition and a reduction in habitat quality. The phenomenon of biotic homogenisation is typical in urban landscapes, but it can proceed differently depending on the scale, a detail that has not been observed in previous studies. This research was carried out in seven Warsaw parks (both public and restricted access). Thirty-four forested areas were randomly selected, some subjected to strong visitors’ pressure and some within restricted access areas, free of such impacts. The latter category included woodlands growing in old forest and secondary habitats. Public access to the study areas contributed to the disappearance of some forest species and their replacement by cosmopolitan non-forest species, leading to loss of floristic biodiversity in areas of high ecological importance at the city scale. Some human-induced factors, including soil compaction and changes in soil pH, moisture and capillary volume, were found to cause habitat changes that favoured native non-forest plants. Despite changes in species composition, the taxonomic similarity of understorey vegetation in both categories—public access and restricted access—was comparable. In a distance gradient of measurements taken around selected individual trees, there was found to be significant variation (in light, soil pH and compaction) affecting the quality and quantity of understorey vegetation (including rare species). In conclusion, the protection of rare forest species could be achieved by limiting access to forested areas, particularly in old forest fragments, and we highly recommend its consideration in the proposal of future park restoration plans. 相似文献
53.
The migration pathways of heavy metals derived from an area previously in agricultural use was investigated in the Wielkopolski
National Park (mid-western Poland). The heavy metals involved (Cd, Cu, Cr, Pb, Ni and Zn) were determined in groundwater,
the springs that feed Lake Góreckie and the lake itself. In order to show how the heavy metals may be set free and what is
their biological availability, soil and sediment samples were subjected to single-stage extraction, using 0.01 M CaCl2, 0.02 M EDTA, 0.005 M DTPA, 0.1 M HCl, 1 M HCl and de-ionised water. Varying metal concentrations were recorded in the water
samples during the study period (from November 2009 to July 2010), usually with higher values in winter and lower ones in
summer. The seasonal changes may be ascribed to natural processes taking place in the ground- and surface waters of Lake Góreckie.
On the other hand, the concentration levels (mostly of Cd, Pb and Cr) are indicative of anthropogenic activity. It should
be mentioned in this context that the highest metal concentrations were found in the soil layer. The concentrations were also
found to exceed both the Polish and the World Health Organization water-quality standards. It appears that the soils are highly
contaminated, mostly with cadmium. The long-lasting effect of acid precipitation in the area makes it possible for immobile
forms to become mobile, thus facilitating further migration into the environment. 相似文献
54.
Christensen TR Jackowicz-Korczyński M Aurela M Crill P Heliasz M Mastepanov M Friborg T 《Ambio》2012,41(Z3):207-217
This article reports a dataset on 8 years of monitoring carbon fluxes in a subarctic palsa mire based on micrometeorological eddy covariance measurements. The mire is a complex with wet minerotrophic areas and elevated dry palsa as well as intermediate sub-ecosystems. The measurements document primarily the emission originating from the wet parts of the mire dominated by a rather homogenous cover of Eriophorum angustifolium. The CO(2)/CH(4) flux measurements performed during the years 2001-2008 showed that the areas represented in the measurements were a relatively stable sink of carbon with an average annual rate of uptake amounting to on average -46 g C m(-2) y(-1) including an equally stable loss through CH(4) emissions (18-22 g CH(4)-C m(-2) y(-1)). This consistent carbon sink combined with substantial CH(4) emissions is most likely what is to be expected as the permafrost under palsa mires degrades in response to climate warming. 相似文献