912 resultados para Darzlubie Forest, Poland


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Geo-ecological transect studies in the pastures of the upper catchment of the HuangHe (99 degrees 30'-100 degrees 00'E/35 degrees 30'-35 degrees 40'N'; 3,000-4,000 in a.s.l., Qinghai province, China) revealed evidence that pastures replace forests. Plot-based vegetation records and fenced grazing exclosure experiments enabled the identification of grazing indicator plants for the first time. The mapping of vegetation patterns of pastures with isolated juniper and Spruce forests raise questions as to the origin of the grasslands, which arc widely classified as "natural" at present. Soil investigations and charcoal fragments of Juniperus (8,153 +/- 63 uncal BP) and Picea (6,665 +/- 59 uncal BP) provide evidence of the wider presence of forests. As temperatures and rainfall records undoubtedly represent a forest climate, it is assumed that the present pastures have replaced forests. Circumstantial evidence arising from investigations into the environmental history of the Holocene effectively substantiates this theory.

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How coniferous trees in northern China changed their distribution ranges in response to Quaternary climatic oscillations remains largely unknown. Here we report a study of the phylogeography of Pinus tabulaeformis, an endemic and dominant species of coniferous forest in northern China. We examined sequence variation of maternally inherited, seed-dispersed mitochondrial DNA (mtDNA) (nad5 intron 1 and nad4/3-4) and paternally inherited, pollen- and seed-dispersed chloroplast DNA (cpDNA) (rpl16 and trnS-trnG) within and among 30 natural populations across the entire range of the species. Six mitotypes and five chlorotypes were recovered among 291 trees surveyed. Population divergence was high for mtDNA variation (G(ST) = 0.738, N-ST = 0.771) indicating low levels of seed-based gene flow and significant phylogeographical structure (N-ST > G(ST), P < 0.05). The spatial distribution of mitotypes suggests that five distinct population groups exist in the species: one in the west comprising seven populations, a second with a north-central distribution comprising 15 populations, a third with a southern and easterly distribution comprising five populations, a fourth comprising one central and one western population, and a fifth comprising a single population located in the north-central part of the species' range. Each group apart from the fourth group is characterized by a distinct mitotype, with other mitotypes, if present, occurring at low frequency. It is suggested, therefore, that most members of each group apart from Group 4 are derived from ancestors that occupied different isolated refugia in a previous period of range fragmentation of the species, possibly at the time of the Last Glacial Maximum. Possible locations for these refugia are suggested. A comparison of mitotype diversity between northern and southern subgroups within the north-central group of populations (Group 2) showed much greater uniformity in the northern part of the range both within and between populations. This could indicate a northward migration of the species from a southern refugium in this region during the postglacial period, although alternative explanations cannot be ruled out. Two chlorotypes were distributed across the geographical range of the species, resulting in lower levels of among-population chlorotype variation. The geographical pattern of variation for all five chlorotypes provided some indication of the species surviving past glaciations in more than one refugium, although differentiation was much less marked, presumably due to the greater dispersal of cpDNA via pollen.

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An inventory of isolated tree stands surrounded by desert pastures in Southern Tibet (A.R. Xizang, China) revealed more than 50 sites with vigorous trees of Juniperus convallium Rehder & E.H. Wilson and Juniperus tibetica Kom and additional more than 10 records where juniper trees had been destroyed between 1959-1976. The tree stands are not restricted to any specific habitat, and occur within an area stretching 650 km westwards from the current forest border of Southern Tibet. The trees are religious landmarks of the Tibetan Buddhists. The highest trees were found at an elevation of 4,860 m. Vegetation records, rainfall correlations and temperature data collected by local climate stations and successful reforestation trials since 1999 indicate that forest relicts fragmented through human interference could regenerate if current cattle grazing and deforestation practices are halted. The drought line of Juniperus forests in Southern Tibet is approximately 200-250 mm/a. A first pollen diagram from Lhasa shows forest decline associated with the presence of humans since at least 4,600 yr BP. The currently degraded commons developed in the last 600 yr. To date, no findings of remains of ancient forests in the Central Tibetan Highlands of the Changtang have been reported.

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How rainfall infiltration rate and soil hydrological characteristics develop over time under forests of different ages in temperate regions is poorly understood. In this study, infiltration rate and soil hydrological characteristics were investigated under forests of different ages and under grassland. Soil hydraulic characteristics were measured at different scales under a 250 year old grazed grassland (GL), a six (6 yr) and 48 (48 yr) year old Scots pine (Pinus sylvestris) plantation, remnant 300 year old individual Scots pines (OT) and a 4000 year old Caledonian Forest (AF). In-situ field saturated hydraulic conductivity (Kfs) was measured and visible root:soil area was estimated from soil pits. Macroporosity, pore structure, and macropore connectivity were estimated from X-ray tomography of soil cores, and from water-release characteristics. At all scales the median values for Kfs, root fraction, macro-porosity and connectivity values tended to AF > OT > 48 yr > GL > 6 yr, indicating that infiltration rates and water storage increased with forest age. The remnant Caledonian Forest had a huge range of Kfs (12 to > 4922 mm h-1), with maximum Kfs values 7 to 15 times larger than 48-year-old Scots pine plantation, suggesting that undisturbed old forests, with high rainfall and minimal evapotranspiration in winter, may act as important areas for water storage and sinks for storm rainfall to infiltrate and transport to deeper soil layers via preferential flow. The importance of the development of soil hydrological characteristics under different aged forests is discussed.

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This study investigated the consistency of a measure of integrative motivation in the prediction of achievement in English as a foreign language in 18 samples of Polish school students. The results are shown to have implications for concerns expressed that integrative motivation might not be appropriate to the acquisition of English because it is a global language and moreover that other factors such as the gender of the student or the environment of the class might also influence its predictability. Results of a hierarchical linear modeling analysis indicated that for the older samples, integrative motivation was a consistent predictor of grades in English, unaffected by either the gender of the student or class environment acting as covariates. Comparable results were obtained for the younger samples except that student gender also contributed to the prediction of grades in English. Examination of the correlations of the elements of the integrative motivation score with English grades demonstrated that the aggregate score is the more consistent correlate from sample to sample than the elements themselves. Such results lead to the hypothesis that integrative motivation is a multi-dimensional construct and different aspects of the motivational complex come into play for each individual. That is, two individuals can hold the same level of integrative motivation and thus attain the same level of achievement but one might be higher in some elements and lower in others than another individual, resulting in consistent correlations of the aggregate but less so for the elements.

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The ammonites Lewesiceras peramplum Mantell and ?Lewesiceras sp. are reported from the Upper Cretaceous in the Nysa Kłodzka Graben; they date from the Middle Turonian and ?Coniacian, respectively. The Middle Turonian limestones of the Stara Bystrzyca quarry contain an abundant assemblage of inoceramids (Inoceramus cuvieri Sowerby and I. lamarcki Parkinson) and other bivalves, including oysters, as well as brachiopods and trace fossils. Micropalaeontological data show the presence of foraminifers and siliceous sponge spiculae, bryozoans, ostracods and fragments of bivalves and gastropods. The Middle Turonian calcareous deposits belongs to the upper part of the Inoceramus lamarcki Zone (late Middle Turonian) and were deposited on a shallow, subtidal offshore shelf. They overlie the Middle Turonian Bystrzyca and Długopole Sandstones, which represent foreshore-shoreface delta deposits. The fossil assemblage suggests a moderate- to low-energy, normal-salinity environment with occasionally an oxygen deficit.

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Wydział Historyczny: Instytut Etnologii i Antropologii Kulturowej

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The paper investigates the relationships between the occurrence of thunderstorms with heavy precipitation (> 30 mm) and atmospheric circulation types. The study covers the period 1951–1998 and is based on a matching span of records of thunderstorm occurrence and daily precipitation totals at 47 weather stations in Poland. A catalogue of circulation types by Osuchowska-Klein, data on frequency of fronts over south-eastern Poland by Niedźwiedź and weather maps were used. In Poland, days with a thunderstorm and more than 30 mm of precipitation are extremely rare and occur mainly in summer. Their recurrence period amounts to about two to four years, with the exception of mountain areas (southern Poland) where they occur nearly every year. The heaviest precipitation on a day with thunderstorm, 166.1 mm, was recorded at a high-mountain station on Mt. Kasprowy Wierch. Apart from this station the highest precipitation was 141.0 mm and only eight stations had at least one record of more than 100 mm. Four regions characterised by different circulation types most favourable for the occurrence of thunderstorms with heavy precipitation were identified. In all of them southerly advection was most favourable for the occurrence of the phenomena studied (Sc, SEc, Sa/c), but that effect was especially prominent in the south-western region. Most of the days with thunderstorm and heavy precipitation coincided with the passing of an atmospheric front over Poland (53.8–81.9% days depending on the station). Days with air-mass thunderstorm and heavy precipitation were rare and mostly occurred in areas of variable topography.

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This paper shows preliminary results of research into the occurrence of strong anticyclonic systems that influenced the weather in Poland during the period 1971–2000. The study was based on NCEP/NCAR reanalysis data, including daily values of the 1000 and 500 hPa geopotential heights, maps of mentioned geopotential heights and maps of sea-level field pressure. With the use of these data a number of exceptionally strong high-pressure systems were identified, together with their areas of origin and subsequent development patterns. They were then broken down into five groups with similar dynamics. The numbers of systems in each group were not found to follow any significant change trends in the long term. The greatest differences between groups were identified in terms of their annual occurrence rates and centre pressure values.

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The paper reviews the provisions of the White Book on National Security of the Republic of Poland. It states that the issue of health security is not given adequate significance there. The accessibility of health services is considered, in general, solely in terms of their availability. The assumptions concerning the concept of providing the number of beds required in a state of threat to national security and in time of war do not take into account the current socio-economic conditions and need to be reviewed. The conclusions emphasize the dilemmas that emerge as a result of the unilateral promotion of a single category of national security, that is military security, in the context of ensuring health security.

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This chapter shows that apart from changes at the systemic and institutional levels, successful reform implementation struggles with a gradual change in academic beliefs, attitudes and behaviours. Currently, visions of the university proposed by the Polish academic community and visions of it proposed by Polish reformers and policymakers (within ongoing reforms) are worlds apart. I shall study recent reforms in the context of specific academic self--protective narratives being produced in the last two decades (at the collective level of the academic profession) and in the context of the Ivory Tower university ideals predominant at the individual level (as studied comparatively through a large--scale European survey of the academic profession). Institutions change both swiftly, radically – and slowly, gradually. Research literature on institutional change until recently was focused almost exclusively on the role of radical changes caused by external shocks, leading to radical institutional reconfigurations. And research literature about the gradual, incremental institutional change have been emergent for about a decade and a half now (Mahoney and Thelen 2010; Streeck and Thelen 2005, 2009; Thelen 2003). Polish higher education provides interesting empirical grounds to test institutional theories. Both types of transformations (radical and gradual) may lead to equally permanent changes in the functioning of institutions, equally deep transformations of their fundamental rules, norms and operating procedures. Questions about institutional change are questions about characteristics of institutions undergoing changes. Endogenous institutional change is as important as exogenous change (Mahoney and Thelen 2010: 3). Moments in which there emerge opportunities of performing deep institutional reforms are short (in Poland these moments occurred in 2009-2012), and between them there are long periods of institutional stasis and stability (Pierson 2004: 134-135). The premises of theories of institutional change can be applied systematically to a system of higher education which shows an unprecedented rate of change and which is exposed to broad, fundamental reform programmes. There are many ways to discuss the Kudrycka reforms - and "constructing Polish universities as organizations" (rather than traditional academic "institutions") is one of more promising. In this account, Polish universities are under construction as organizations, and under siege as institutions. They are being rationalized as organizations, following instrumental rather than institutional logics. Polish academics in their views and attitudes are still following an institutional logic, while Polish reforms are following the new (New Public Management-led) instrumental logics. Both are on a collision course about basic values. Reforms and reformees seem to be worlds apart. I am discussing the the two contrasting visions of the university and describing the Kudrycka reforms as the reistitutionalization of the research mission of Polish universities. The core of reforms is a new level of funding and governance - the intermediary one (and no longer the state one), with four new peer-run institutions, with the KEJN, PKA and NCN in the lead. Poland has been beginning to follow the "global rules of the academic game" since 2009. I am also discussing two academic self-protection modes agains reforms: (Polish) "national academic traditions" and "institutional exceptionalism" (of Polish HE). Both discourses prevailed for two decades, none seems socially (and politically) acceptable any more. Old myths do not seem to fit new realities. In this context I am discussing briefly and through large-scale empirical data the low connectedness to the outside world of Polish HE institutions, low influence of the government on HE policies and the low level of academic entrepreneurialism, as seen through the EUROAC/CAP micro-level data. The conclusion is that the Kudrycka reforms are an imporant first step only - Poland is too slow in reforms, and reforms are both underfunded and inconsistent. Poland is still accumulating disadvantages as public funding and university reforms have not reached a critical point. Ever more efforts lead to ever less results, as macro-level data show. Consequently, it may be useful to construct universities as organizations in Poland to a higher degree than elsewhere in Europe, and especially in Western Europe.

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There is growing evidence that organo-nitrogen compounds may constitute a significant fraction of the aerosol nitrogen (N) budget. However, very little is known about the abundance and origin of this aerosol fraction. In this study, the concentration of organic nitrogen (ON) and major inorganic ions in PM2.5 aerosol were measured at the Duke Forest Research Facility near Chapel Hill, NC, during January and June of 2007. A novel on-line instrument was used, which is based on the Steam Jet Aerosol Collector (SJAC) coupled to an on-line total carbon/total nitrogen analyzer and two on-line ion chromatographs. The concentration of ON was determined by tracking the difference in concentrations of total nitrogen and of inorganic nitrogen (determined as the sum of N-ammonium and N-nitrate). The time resolution of the instrument was 30 min with a detection limit for major aerosol components of ∼0.1 mu;gm-3. Nitrogen in organic compounds contributed ∼33% on average to the total nitrogen concentration in PM2.5, illustrating the importance of this aerosol component. Absolute concentrations of ON, however, were relatively low (lt;1.0 mu;gm-3) with an average of 0.16 mu;gm-3. The absolute and relative contribution of ON to the total aerosol nitrogen budget was practically the same in January and June. In January, the concentration of ON tended to be higher during the night and early morning, while in June it tended to be higher during the late afternoon and evening. Back-trajectories and correlation with wind direction indicate that higher concentrations of ON occur in air masses originating over the continental US, while marine air masses are characterized by lower ON concentrations. The data presented in this study suggests that ON has a variety of sources, which are very difficult to quantify without information on chemical composition of this important aerosol fraction.