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PL
Pożary w lasach, poza stratami dla gospodarki człowieka, zmieniają drastycznie właściwości abiotyczne i biotyczne środowiska leśnego zarówno w czasie jak i przestrzeni. W wyniku pożaru obserwuje się spadek liczebności oraz różnorodności taksonomicznej mikro- i mezofauny glebowej co ma niebagatelny wpływ na kształtowanie metabolizmu ekosystemów glebowych. Celem podjętych badań była ocena dynamiki zmian liczebności mikroorganizmów i mezofauny glebowej w glebie i ściółce w zależności od intensywności pożaru jak również od okresu czasu po pożarze. Badania przeprowadzono w północno-wschodniej części Kampinoskiego Parku Narodowego. Badaniami objęto obszary wypalone – powstałe na skutek „mocnego”(Mp) i „słabego”(Sp) pożaru, oraz sąsiadujące z nimi obszary niewypalone – kontrolowane w 2., 14. i 28. miesiącu po pożarze który miał miejsce w czerwcu 2015 r. Na podstawie uzyskanych wyników stwierdzono, że intensywność pożaru jak również czas upływający od żywiołu kształtuje liczebność populacji bakterii i grzybów mikroskopowych oraz mezofauny w glebie. Wyniki badań wskazują na powolną regenerację zespołów mikroorganizmów i mezofauny na pożarzyskach. Na tempo regeneracji i różnorodność gatunkową wpływ mają obszary niewypalone sąsiadujące z pożarzyskiem.
EN
Fires in forests apart from human losses for the economy, drastically change the properties of abiotic and biotic forest environment in both time and space. As a result of the fire, there is a decrease in the number and taxonomic diversity of soil microorganisms and mesofauna, which has a significant impact on the formation of metabolism of soil ecosystems. The aim of this study was to evaluate the dynamics of changes in the number of microorganisms and soil mesofauna in soil and litter depending on the intensity of the fire, as well as the period of time after the fire. The study was conducted in the north-eastern part of the Kampinos National Park. The study included areas burnt – resulting from a "strong" (Mp) and "weak" (Sp) fire, and the adjacent areas unfired – controlled 2, 14 and 28 months after the fire that took place in June 2015. Based on the obtained results, it was found that the intensity of the fire, as well as the time elapsing from the fire, shapes the population of bacteria, microscopic fungi and mezofauna in the soil. The results of the research indicate slow regeneration of microorganism and mesofauna assemblages during firefighting. Regeneration and species diversity are affected by unburnt areas adjacent to a fire.
2
Content available remote Short-term effects of prescribed forest fire on soil mites (Acari)
EN
Natural forest fires are considered as a part of natural ecosystem processes. Short-term effects of prescribed fire on densities and taxonomic diversity of soil Acari were studied in fresh pine mixed forest ("Biala" forest ) in the Mazovia region, Central-Eastern Poland. Three plots (size 1 m2) of similar soil type and vegetation were selected for prescribed burning. Soil samples of an area of 10 cm2 and the depth of 5 cm were collected in June 2005 - one day after the burning, 60 days after the burning and 90 days after the burning. Samples were collected from within the border of the burned plots, from the border itself, as well as from the surroundings. Due to the burning, the density of Acari communities decreased from 11.5 x 103 ind. m[^-2] recorded in the surroundings to 3.2 x 103 ind. m[^-2] recorded in the burned plots. Values recorded within the burned plots after the fire differed significantly from those recorded on the border (P = 0.05) and in the surroundings (P = 0.0001). After 60 days, an increase in Acari abundance was observed in the burned plots (P = 0.02), becoming similar to that noted for the border of the plot and for the surroundings. After 90 days, there were no significant differences between the burned parts of the plots, their borders and the surroundings; however, generally decreased densities were observed, possibly due to the seasonal reason. The observed changes suggest the restoration of Acari community after disturbance.
EN
We report on the temperature dependences of polarized reflectance spectra of ß”-(bis(ethylenedithio) tetrathiafulvalene)2SF5CH2SO3. The material remains in the charge-ordered state over the whole temperature range. Room temperature infrared spectra display the response characteristic of a quasi-twodimensional organic conductor, with a broad mid-infrared electronic excitation and a number of vibrational features related to intramolecular modes of both the bis(ethylenedithio)tetrathiafulvalene (ET) donor molecule and the SF5CH2SO3 anion. Upon lowering the temperature, unusual activation of intramolecular modes of ET is observed. We suggest that this effect is connected with electronmolecular vibration coupling within a dimerized lattice.
EN
The communities of soil mesofauna were studied in the year 2004 along three transects crossed shelterbelts of different age (6, 11 and 170 years old) and adjacent wheat fields at a distance of 0.5, 15 and 50 m. Studies were carried out in the Gen. D. Chłapowski Landscape Park near Turew, Western Poland (16 [degrees] 45'E, 52 [degrees] 01'W). The age of shelterbelts vegetation affected soil mesofauna of adjacent fields in a diverse way. The mean density of mites amounts 7.4 x 10[^3] ind. m[^-2] and 2.6 x 10[^3] ind. m[^-2] respectively for the shelterbelts and fields. Densities of Acarina communities were affected not only by the presence of a shelterbelt (P = 0.000) but also its age (P = 0.02) and the distance from it (P = 0.000), and these effects were similar in spring and autumn (P = 0.08). The mean density of springtail noted in shelterbelts of different age was 2.0 x 10[^3] ind. m[^-2]. Although the effect of the the shelterbelts. age on the density of Collembola was not found (P= 0.3), the densities were different in shelterbelts and in adjacent fields (P = 0.006) but statistical significance was found only between spring and autumn (P = 0.000). The distance from the shelterbelt influenced (though less intensely) the density of Collembola on adjacent field (P = 0.01). Eighteen species of Collembola were found in studied shelterbelts and fields. Isotoma notabilis Schaff. usually dominated in shelterbelts. Its contribution to abundance of communities varied depending on the age of shelterbelts (in 6 years old shelterbelt it constituted as many as 71% of the whole community). In 11 years old shelterbelt Schoetella ununguiculata (Tullb.), was more common than Isotoma notabilis Schaff. and in the 170 years old shelterbelt the dominant species was Onychiurus armatus (Tullb.). Proisotoma minuta (Tullb.), Isotoma notabilis or Onychiurus armatus dominated in adjacent fields though their contribution was depended on shelterbelt.s age and on the distance from it.
EN
Density of microarthropods, Collembola and Acarina were studied in 2000 in soil and litter of 7-years old shelterbelt and in nearby field sown by winter wheat in Turew (Wielkopolska Region, West Poland). Samples were taken in the shelterbelt centre and in the field at a distance of 0.5 m, 10m and 50 m from the tree line. Collembola were analysed in soil and in litter samples placed in containers and located in different sited, Acarina only in soil samples. Density of Collembola in soil was found to be higher in the shelterbelt than in the adjacent field (P=0.003). Similar relationship was not, however, noted for insects in litter, density in open field was higher than in the shelterbelt. Density of Acarina in soil decreased gradually with the distance from the shelterbelt (P=0.007). Twenty three species of springtails were found; the highest species richness (12) was noted in shelterbelts, but also in the litter in the open field. The dominant species common for soil and litter were Isotoma notabilis in the shelterbelt while Isotomina thermophila and Isotoma viridis in the field. With the increasing distance from shelterbelt Proisotoma minuta increased its contribution to the soil community, Entomobrya multifasiata was the dominant only in litter. In the field soil, 50 m from woods, the highest share of young individuals was noted. The highest species richness of Oribatida was found in the field margin (18). The Tectocepheus velatus was the dominant species both in the shelterbelt and the field, accounted for 30-70% of the total number of individuals.
EN
We report the room-temperature polarized infrared reflectance spectra of two radical cation salts based on halogenated TTF and two-dimensional polymeric iodoplumbate or Ag-doped iodoplumbate anions. These salts were ß-(EDT-TTF-I2)2(Pb5/6a1/6I2)3 and ß-(EDT-TTF-I2)2(Pb2/3+xAg1/3-2x??xI2)3, where x = 0.05 and a is a vacancy. Both materials display a metallic response, characteristic of quasi-onedimensional organic conductors. The ß-(EDT-TTF-I2)2(Pb2/3+xAg1/3-2x??xI2)3 salt, with x = 0.05 is partly transparent along the lowest conductivity direction in the infrared frequency range. The single-crystal polarized absorption spectrum recorded in this direction displays a number of vibrational features related to the intramolecular modes of the EDT-TTF-I2 molecule, which are assigned using available normal mode calculations. In addition, the absorption spectrum of the ß-(EDT-TTF-I2)2(Pb2/3+xAg1/3-2xaxI2)3 material dispersed in a KBr pellet is reported and discussed.
EN
Spectral investigations of selected tetrathiafulvalene-derived donor molecules (TTFs) and the fullerene-derived adducts with these donors linked to them were performed. The main attention has been devoted to studies of possible intermolecular interactions, in particular to aggregation processes in these materials.
8
PL
W dniach 1-5 września 2001 r. w Poznaniu odbyło się międzynarodowe spotkanie naukowe "Niskowymiarowe i nanostrukturalne materiały molekularne dla zaawansowanych zastosowań" (NATO Advanced Research Workshop: Molecular Low Dimensional and Nanostructured Materials for Advanced Applications), zorganizowane przez Instytut Fizyki Molekularnej PAN w Poznaniu. Spotkanie to, którego dyrektorami byli profesorowie Andrzej Graja, V.M. Agranovich i Francois Kajzar, zorganizowano pod auspicjami i przy wydatnym wsparciu | finansowym NATO. Pozostali główni sponsorzy to Komitet Badań Naukowych, Instytut Fizyki Molekularnej PAN, Komitet Fizyki PAN, Polski Koncern Naftowy ORLEN, Lambda Physik i W.L. Electronics Bruker-Service.
EN
Extended spectral investigations of several new bis-linked tetrathiafulvalenes (TTFs) to [60]fullerene were performed. From VIS-NIR-IR spectra it was stated, that charge redistribution on C60 and TTFs moieties in the adducts occurs after their formation. This redistribution depends not only on the nature of a substituent but also on the number of bounded donors. Vibrational features of the polyadducts were also analyzed.
EN
Nitrates and nitrites in natural samples are determined by ion chromatography and spec-trophotometric methods. The spectrophotometric method most often used for the determination of nitrites is the Griess-IIosvay one, based on the reaction of diazotization of the primary aromatic amines followed by coupling of diazonium salts yielding azo dye. The same method can be used for the determination of nitrates, after their reduction to nitrites. In this study the Griess-Ilosvay method was applied with different diazotizing and coupling reagents. The diazotizing reagents were the sulfonamides: sulfamethazine, sulfacetamide, sulfamethizole, sulfadimethoxine and sulfisomidine. The coupling reactions were carried out using either 1 -naftol-4-sulfonic acid (NSA) or 8-amino-2-naphtha-lenesulfonic acid (CA). Basic studies were performed in order to establish the conditions of diazotization and coupling. The limits of determination, the range of linearity, accuracy and precision of the method and molar absorption coefficients were determined. The system sulfamethazine-CA was used for the determination of nitrates and nitrites in hard cheese. In 8 selected kinds of hard cheese the concentration of nitrite nitrogen varied in the range from 0.052 to 0.356 ug g(-1) and that of nitrate nitrogen - from 0.212 to 8.559 ugg(-1). • The method applied was shown to be characterised by good accuracy and precision.
PL
Azotany i azotyny w próbkach naturalnych oznacza się metodą chromatografii jonów i metodami spektrofotometrycznymi. Z metod spektrofotometrycznych oznaczania azotynów najczęściej jest stosowana metoda Griessa-Ilosvaya, oparta na reakcji diazowania pierwszorzędowych amin aromatycznych i następnie sprzęganiu soli diazoniowych, w celu otrzymania barwnika azowego. Obok azotynów metodą tą oznaczyć można także azotany, po uprzedniej redukcji do azotynów. W pracy badano reakcję Griessa-Ilosvaya z zastosowaniem różnych odczynników diazujących i sprzęgających. Jako odczynniki diazujące stosowano sulfonamidy: sulfametazynę, sulfacetamid, sulfametizol, sulfa-dimetoksynę i sulfisomidynę. Reakcje sprzęgania przeprowadzono z kwasem 1-naftolo-4-sulfonowym (NSA) lub 8-amino-2-naftalenosulfonowym (CA). Wykonano badania podstawowe. Ustalono warunki diazowania i sprzęgania oraz wyznaczono granice oznaczalności, zakres prostoliniowości wskazań, dokładność i precyzję metody, a także molowe współczynniki absorpcji. Układ sulfametazyna-CA zastosowano do oznaczania azotynów i azotanów w serach twardych. W 8 wybranych serach oznaczono zawartość azotu azotynowego w zakresie od 0.052 do 0.356 ugg(-1) i azotu azotanowego od 0.212 do 8.559 ugg(-1). Metoda charakteryzuje się dobrą dokładnością i precyzją.
EN
In 1987-1989 a lysimetric experiment was designed to determine the effect of species composition of grass cultures (mono- and polyculture cultures) on Collembola communities, and to examine correlations between the abundance of Collembola and other soil organisms. Also the dependence of Collembola abundance on plant biomass was examined. Two plant communities were under study: simplified (Dactylis glomerata - monoculture) and comprising several species (a mixture of six grass species - polyculture). Plastic 0.16 m^2 lysimeters were used, filled with alluvial soil made up of coarse sand. The soil was watered and fertilized with earthworm casts. The simplification of the plant community had an unequivocal effect on the density and species diversity of collembolans. Watering and fertilization accounted for an increase in the density of collembolans only in the upper soil layer of the severalspecies plant community. Fertilization had a shortterm effect, noticeable within 30 days after the introduction of casts. Cryptopygus bipunctatus, a pioneer species, was the dominant, accounting for over 50% of the community in the upper soil layer and for 30% in the lower layer.
EN
Comparisons between the carabid communities of natural and drained fens in the Biebrza Valley (NE Poland) were made on the basis of trapped material. Fen drainage appears to result in a restructuring of species composition as there is only a limited (20-40%) similarity between the communities in natural and drained areas. The lowest species diversity was noted for a drained meadow on alder peat. Agonum moestum was dominant on natural fens, and in the one not cultivated and periodically flooded site on drained fens and Carabus granulatus or Pterostichus nigrita on drained ones. Tropic structure also differed, with hemizoophages of the genera Amara and Harpalus associated with agrocoenosesbeing present on drained fens but absent from natural ones. Chlaenius costulatus, a species now rare in Poland, is typical of peatlands, but was not present on drained sites. The number of sites accesible for it have declined as a result of wetland drainage.
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