Search results for "Moss"
showing 10 items of 228 documents
Magnetic and structural properties of the nanostructured Fe 1–x Si x system with x = 0.1, 0.2 and 0.3, mechanical alloyed and sintered
2007
The magnetic and structural properties of the nanostructured system Fe1–xSix with x = 0.1, 0.2 and 0.3 were studied by X-Ray diffraction (XRD), SEM, and Mossbauer Spectrometry (MS). The samples were prepared by compacting and sintering at two temperatures, 900 and 1000 uC, from powders obtained by means of two procedures: by elemental mixing of Fe and Si powders and by mechanical alloying (MA). For samples obtained from mixed powders and sintered at 900 and 1000 uC, XRD and MS show the presence of pure iron and silicon, indicating that these conditions do not favor alloying, except for the sample with 30 at.% and 1000 uC, for which, besides of iron and silicon patterns, the DO3 and FeSi pha…
Chronic cocaine exposure impairs progenitor proliferation but spares survival and maturation of neural precursors in adult rat dentate gyrus
2006
Recent observations indicate that drugs of abuse, including alcohol and opiates, impair adult neurogenesis in the hippocampus. We have studied in rats the impact of cocaine treatment (20 mg/kg, daily, i.p.) on cell proliferation, survival and maturation following short-term (8-day) and long-term (24-day) exposure. Using 5'-bromo-2-deoxyuridine (BrdU) and Ki-67 as mitotic markers at the end of the drug treatments, we found that both short- and long-term cocaine exposures significantly reduced cell proliferation in the dentate gyrus (DG) of the hippocampus. By labelling mitotic cells with BrdU pulses before or during the early stages of the drug treatment, we determined that long-term cocaine…
<strong>Microhabitat preference of caddisfly (Trichoptera) communities in a medium-sized lowland stream in Latvia</strong>
2011
The microhabitat preference of caddisfly (Trichoptera) communities was studied in 8 types of microhabitats in a fast-flowing, medium-sized, lowland stream in Latvia. A total 36 caddisfly taxa belonging to 14 families were recorded in microhabitat samples. A PCA biplot of caddisfly taxa abundance in microhabitats showed 3 distinct caddisfly taxa groups: depositional [Limnephilidae Gen. sp., Anabolia laevis (Zetterstedt) and Lasiocephala basalis (Kolenati)], lithal [ Agapetus ochripes Curtis and Psychomyia pusilla (Fabricius)], and submerged macrophyte and water moss caddisfly microhabitat communities ( Ithytrichia lamellaris Eaton, Hydropsyche siltalai Dohler and Hydropsyche spp. juv.). The …
Mosses as a biomonitor to identify elements released into the air as a result of car workshop activities
2022
Human activity as a result of civilization development contributes to creating new sources of environmental pollution. Air pollution is one of the major problems because it affects the fauna and flora, and people themselves. There is a lack of public awareness of the level of atmospheric analytes pollution emitted from people's occupational and recreational (leisure) activities. A quick, cheap and easy way to investigate the state of the environment is to use organisms-biomonitors that indicate the level of environmental pollution. The study aimed to assess air pollution in an urban area using three moss species: Sphagnum fallax, Pleurozium schreberi and Dicranum polysetum. Mosses were expo…
Recovery of macroinvertebrate communities from stream habitat restoration
1998
1. Many streams channelized for timber floating in Finland are now being restored to their original condition. The most frequently used restoration structures are boulder dams, flow deflectors, excavations and channel enlargements. By increasing substrate heterogeneity and leaf litter retention, restoration may enhance the formation of detritivore-dominated macroinvertebrate assemblages. In this study, macroinvertebrate communities in streams with differing recovery periods (from 0 to 16 years) from restoration, were compared with those in channelized and near-pristine streams. 2. Water depth and current velocity were lower, and relative bed roughness higher in restored than in dredged chan…
Using moss and lichens in biomonitoring of heavy-metal contamination of forest areas in southern and north-eastern Poland.
2017
Abstract In the years 2014–2016 biomonitoring studies were conducted in the forest areas of south and north-eastern Poland: the Karkonosze Mountains, the Beskidy Mountains, the Borecka Forest, the Knyszynska Forest and the Bialowieska Forest. This study used epigeic moss Pleurozium schreberi and epiphytic lichens Hypogymnia physodes. Samples were collected in spring, summer and autumn. Approximately 500 samples of moss and lichens were collected for the study. In the samples, Mn, Ni, Cu, Zn, Cd, Hg and Pb concentrations were determined. Based on the obtained results, the studied areas were ranked by extent of heavy-metal deposition: Beskidy > Karkonosze Mountains > forests of north-eastern …
Characterization of the Etna volcanic emissions through an active biomonitoring technique (moss-bags): Part 1 – Major and trace element composition
2013
Active biomonitoring using moss-bags was applied to an active volcanic environment for the first time. Bioaccumulation originating from atmospheric deposition was evaluated by exposing mixtures of washed and air-dried mosses (Sphagnum species) at 24 sites on Mt. Etna volcano (Italy). Concentrations of major and a large suite of trace elements were analysed by inductively coupled mass and optical spectrometry (ICP-MS and ICP-OES) after total acid digestion. Of the 49 elements analysed those which closely reflect summit volcanic emissions were S, Tl, Bi, Se, Cd, As, Cu, B, Na, Fe, Al. Enrichment factors and cluster analysis allowed clear distinction between volcanogenic, geogenic and anthropo…
Use of Lichen and Moss in Assessment of Forest Contamination with Heavy Metals in Praded and Glacensis Euroregions (Poland and Czech Republic)
2011
The concentrations of selected metals-Cr, Ni, Cu, Zn, Cd, and Pb-were determined in the samples of Hypogymnia physodes lichen and Pleurozium schreberi moss collected in Polish and Czech Euroregions Praded and Glacensis. More specifically, the samples were collected in Bory Stobrawskie, Bory Niemodlińskie, and Kotlina Kłodzka (Poland) and in Jeseniki (Czech Republic). The concentration of metals in the samples was measured using the atomic absorption spectrometry (flame AAS technique and electrothermal atomization AAS technique). The results were used to calculate the comparison factor (CF) that quantifies the difference in concentration of a given bioavailable analyte × accumulated in liche…
Effects of tobacco smoke on indoor air quality: the use of mosses in biomonitoring.
2020
This research was carried out to assess the possibility of using Pleurozium schreberi mosses as bioindicators of atmospheric aerosol pollution in living quarters (kitchen and bedroom), with metals originating from tobacco smoke from various types of cigarettes: conventional cigarettes, e-cigarettes and heated tobacco products. The moss-bag method of active biomonitoring was used. The mosses were exposed in these indoor spaces for three months and, after the exposition period, their analytes – Ni, Cu, Zn, Cd and Pb – were determined using flame atomic absorption spectrometry (F-AAS). Results were interpreted using the relative accumulation factors (RAF), coefficients of variation (CV) and th…
The use of mosses in biomonitoring of selected areas in Poland and Spitsbergen in the years from 1975 to 2014
2015
We have compared historical changes in concentrations of the heavy metals Mn, Ni, Cu, Zn, Cd and Pb accumulated in samples from the Polish woodlands of Beskidy and Karkonosze (S, SE Poland) and the north-east regions of the country, versus the relatively little polluted areas of Spitsbergen of the Svalbard Archipelago. We have combined the results from literature with new results from 2014. The regions of Beskidy and Karkonosze were the most exposed to heavy metals deposition. However, from 1975 to 2014 there was a considerable decrease of concentrations of Cu, Zn, Cd and Pb at all Polish sites, clearly signifying improvement of environmental quality. For example, the average Cd concentrati…