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41.
Road traffic emits a cocktail of pollutants that can influence the vegetation and plant diversity in neighboring areas. However, the recovery potential of bryophytes after traffic abandonment is still little explored. In addition, the effects of the main pollutants of road verges, such as metals and salinity, on moss flora need to be investigated. In our study, we compared the moss richness and diversity in two closely related veteran tree allees of high conservation importance. The allees in Gry?ów and Lubrza, Poland, were chosen because of their similarity in age, geographical location, type of surrounding areas, and tree species. The only difference was that the trees in Gry?ów had not been exposed to direct road pollution for almost 30 years. The moss richness and diversity differed significantly between the sites. Altogether, 20 moss species were recorded on 229 trees, 17 species in Gry?ów (abandoned road), and 13 in Lubrza (busy road). We found considerable differences between moss cover on the road-facing and opposite sides of tree trunks. In Lubrza, mosses on the road-facing side were very scarce. The moss cover in Gry?ów was highly balanced between trunk sides as well as among trunk heights. Typical epiphytic species such as Bryum moravicum, Dicranoweisia cirrata, Leskea polycarpa, and Orthodicranum tauricum preferred the Gry?ów tree stands, where they were present in numbers almost twice as high as that at Lubrza. The study shows that constructing a bypass road could be an effective conservation measure for veteran tree protection with their epiphytic moss flora.  相似文献   
42.
Prolonged exposure to hand-arm vibration (HAV) generated by chainsaws can cause HAV syndrome, i.e., disorders in the upper extremities of forestry workers. Progress of HAV syndrome depends on the intensity of mechanical vibration transmitted throughout the body, which is directly proportional to coupling forces applied by the woodcutter to a vibrating tool. This study aimed to establish a method of measuring coupling forces exerted by chainsaw workers in real working conditions. Coupling forces exerted by workers with their right and left hands were measured with a hydro-electronic force meter. Wood hardness, the type of chainsaw and the kind of forest operation, i.e., felling, cross-cutting or limbing, were considered.  相似文献   
43.
The paper analyses the selected optical parameters of protective optic filters used for protection of the eyes against hazardous radiation within the visible (VIS) and near infrared (NIR) spectrum range. The indexes characterizing transmission and reflection of optic radiation incident on the filter are compared. As it follows from the completed analysis, the newly developed interference filters provide more effective blocking of infrared radiation in comparison with the currently used protective filters.  相似文献   
44.
In soil magnetometry, two types of measurements are usually performed. The first type is measurements performed on the soil surface, frequently using an MS2D sensor. The second type includes measurements of magnetic susceptibility carried out in the soil profile, usually to a depth of about 30 cm. Up to now, such measurement results were analyzed separately. However, it is possible and advantageous to integrate these two types of measurements. The goal of the study was to integrate measurements of magnetic susceptibility performed on the soil surface and in the soil profile. More specifically, the goal was to obtain 3-dimensional spatial distributions of magnetic susceptibility of the topsoil horizon. Results show that it is possible to effectively integrate measurements of magnetic susceptibility performed on the soil surface and in the soil profile. Moreover, the 3-dimensional spatial distribution that is obtained shows the magnetic susceptibility of the top 20 cm of soil, which includes the soil horizons where most of the heavy metals are accumulated. The analysis of such a spatial distribution can be very helpful in delineating areas where the heightened magnetic susceptibility is a result of the influence of anthropogenic pollution from those areas where it results from lithogenic origin. It is possible to investigate where the volumes of soil with heightened magnetic susceptibility are located in the soil profile and in this way investigate which characteristic type of soil profile it is.  相似文献   
45.
Abstract

The objective of the study is to attempt an evaluation of heart rate (HR) and heart rate variability (HRV) regulatory mechanisms in the presence of autonomous nervous system (ANS) components in transient exposure to high altitude hypoxia.

During 24 hrs including a stay in hypobaria, the participants had their HR continuously recorded using the Holter method. The following parameters were calculated at rest and during the stay in a thermobarochamber: spectral power in low frequency bands (LF) 0.04-0.15 Hz and high frequency bands (HF) 0.15-0.5 Hz, and the sympathetic-parasympathetic balance index LF/HF.

Under hypobaric conditions, a decrease in mean spectral power of R-R intervals was noted within both frequency ranges, compared with the study performed in normobaria. The observed differences were larger at daytime.  相似文献   
46.
This work presents mineralogical and chemical characteristics of weathering crusts developed on sandstones exposed to various air pollution conditions. The samples have been collected from sandstone tors in the Carpathian Foothill and from buildings in Kraków. It has been stated that these crusts differ in both fabric and composition. The sandstone black crust from tors is rich in organic matter and composed of amorphous silica. Sulphate incrustations accompanied by dust particles have been only sometimes observed. Beneath the black crust, a zone coloured by iron (oxyhydr)oxides occurs. The enrichment of the surface crust in silica and iron compounds protects the rock interior from atmospheric impact. The sandstones from architectonic details are also covered by a thin carbon-rich black crust, but they are visibly loosened. Numerous salts, mainly gypsum and halite, crystallise here, thus enhancing deterioration of the rock. Moreover, spherical particles originated from industrial emissions are much more common. Gypsum in natural outcrops, forms isolated and well-developed crystals, whilst these found on the architectonic details are finer and densely cover the surface. Such diversity reflects various concentrations of acid air pollutants in solutions.  相似文献   
47.
Environmental Science and Pollution Research - Anaerobic ammonium oxidation (anammox) is one of the most promising processes for the treatment of ammonium-rich wastewater. It is more effective,...  相似文献   
48.
Physical, chemical and biochemical properties of silver nanoparticles(AgNPs) depend to a great extent on their size, shape, size distribution, and stabilizers located on their surface. This study focused on two typical stabilizers, namely citrates(cit), low molecular ions protecting nanoparticles by electrostatic repulsion, and polyvinylpyrrolidone(PVP), a hydrophilic, neutral, high molecular polymer protecting nanoparticles by steric stabilization. Natural bacterioplankton was collected from a eutrophic, downtown lake and exposed to five concentrations(0.1–5 mg/L) of AgNPs-PVP and AgNPs-cit. Responses were monitored after 1, 3, 5 and 7 days of exposure, by evaluating the survival rate of bacteria, their respiratory activity, and the general activity of extracellular esterases. A significantly better(greater) survival rate of bacterioplankton was observed in water with an addition of AgNPs-cit. The inhibition of extracellular esterases was observed only in samples containing AgNPs-PVP. The inhibitory effect increased proportionally to the concentration of AgNPs-PVP applied. Within the studied concentration range, there was no statistically significant inhibition of bacterioplankton respiratory activity by AgNPs-PVP and AgNPs-cit.  相似文献   
49.
The European Landscape Convention indicates that assessment of different dimensions that exist in landscapes should be taken into account in planning. In this study, we first investigated ecological, cultural and social values as perceived by the local people in a highway-planning process in Sweden. Next, we explored which factors influenced the local people's participation in the road-planning process. We used questionnaires, planning documents and the Theory of Planned Behavior to investigate the relations between different factors and local people's participation in the planning process. The results showed that people presumed the ecological values in the landscape to be adversely affected by the new road, while the social values would remain the same. Landowners had heard of the participatory-process, but few participated. Those who lived within 300 m of the road were more active in the planning process than people living further away. The findings suggest that people living within a few hundred metres of the road should be treated as key stakeholders in the planning process. The involvement of other stakeholders, and when in the public participation process stakeholders should be involved, is also discussed.  相似文献   
50.
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