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Soil iron and manganese fractionation is evaluated in the soil profile sampled from a pine-covered area of Wielkopolski National Park (mid-western Poland), that for years has been exposed to acid rain. The soils studied are sands and loamy sands with a pH of 3.3-4.4. The content of iron and manganese was analyzed by sequential extraction in the following fractions: exchangeable, acid extractable, reducible, oxidizable, and residual. The soil profile displays a lithogenically dichotomous structure that is reflected in the iron and manganese content, especially in the Fe residual fraction and Mn oxidizable fraction. In terms of the lability of manganese, it can be stated that the amount of manganese in reducible fractions (Mnred) is higher than in exchangeable and acid extractable ones (except in the surface layer), while the amounts of manganese in fractions in which it is poorly available (Mnox) and unavailable (Mnres) are lower than that of Mnred. For iron, this sequence looks as follows: Feex
Seed dispersal distance is influenced by a variety of seed properties and functional responses of dispersers. However, to our knowledge, how and why seed dispersal distances are determined remains poorly understood. In the present study, seeds of sympatric tree species, Pinus koraiensis, Corylus mandshurica, Corylus heterophylla, and Quercus mongolica were released to investigate the effects of rodent abundance, seed type, and seed availability on seed dispersal. Our results showed that seeds of P. koraiensis were dispersed further than those of C. heterophylla and C. mandshurica regardless of the ambient rodent and seed abundances, reflecting a consistent effect of seed type on seed dispersal distances. Seed dispersal distance was greatly facilitated by lower per-capita seed abundance (the ratio of seeds to rodents); however, seed caching and cache survival were benefited from higher per-capita seed abundance. Although seed dispersal and seed caching of a particular tree species can be enhanced by its own seed availability, no consistent influence was detected at interspecific levels, reflecting different interspecific effects of seed availability on seed dispersal of sympatric seed species. Our results provide evidences that the effect of seed availability on seed dispersal should be evaluated in terms of per-capita seed abundance and interspecific effects, rather than the independent influence of seed or disperser abundances.
Subject and purpose of work: The aim of the article is to determine the level of accessibility of personal computers and the Internet and their use for distance work by professionally active persons with disabilities living in rural areas throughout Poland. Materials and methods: Surveys were carried out during the period from June 30, 2010, to May 31, 2011, on a sample of 5,000 persons with disabilities, 1359 of whom, during the last 30 days of the survey, were gainfully employed - they were professionally active. The area of research included randomly selected rural and urbanrural communes in sixteen provinces. Results: Personal computers and the Internet are most often used by the group of young people with disabilities and those who conduct their business activities in communes. Personal computers and the Internet are most often used by disabled persons with physical, sensory and complex disorders. Conclusions: It is necessary to intensify organisational, technical and legal activities and efforts that will contribute to a fuller and wider use of computers, the Internet and other assistive technology by people with disabilities.
An organic-mineral fertilizer obtained from brown coal, the Rekulter when applied to polluted soil increased the content of the total organic carbon and pHKCl. The content of Cd and Zn soluble in 1M HCl were approximately 80% and for Ni and Pb were about 90% of the total content. The content of soluble Zn, Pb, Cd and Ni in 0.01 CaCl2 decreased when the application rate of the Rekulter was increased. The Rekulter reduced the content of cadmium soluble in 0.01 CaCl2 on average by 62% and nickel by 81% compared to pots not fertilized with this preparation. In the case of lead the decrease was about 2% and for zinc, about 35%.
This paper presents main problems associated with flat renting in Poland. The authors identify the housing resources that constitute the main source of rented flats.
The paper presents the results of studies concerning the availability and possibilities of the use of wood for energy purposes in Europe and in Poland. It describes in detail the current use of wood for energy production purposes, as well as predictions on volume, composition, and sources of energy wood. It also presents the results concerning potential impact of energy wood harvesting on wood industries. The paper concludes that the question of utilization of forest biomass for large-scale energy generation is very complex and has far-reaching consequences for environment, society and economy. So as to be effective, wood resources management should give a priority to wood-based production of the greatest added value, and energy generation should be a closing-down stage in the wood value chain.
Therapeutic agents of natural origin, administered in prostatic disorders, have wider ex­perimental and clinical documentation than the synthetic medicines, fashionable, butrela- t/ve/y new on the market. Their superiority is based first of all on versatile points of effect, almost total lack of side effects and a significantly low cost of therapy. Bearing in mind the above mentioned, an attempt was made to produce an oral solid form of a drug from dry aqueous extract of small-flowered willow herbs (E. parviflorum), using some formulating components of variable adsorptive properties. Taking into account the composition and granulometric properties of the extract, two alternative technological processes have been suggested to produce oral solid model phar­maceutical agents. These model forms were subjected to the following morphological tests determining: the appearance of tablets, their mass, friability and effective disintegration time. Furthermore, pharmaceutical availability of the model form of the drug was investigated. The effect of formulating components on the course of quantitative determination of active agents was assessed in the tablets.
European yew (Taxus baccata) is a rare and endangered species in many European countries. Observations of high levels of T. baccata seedling mortality under the canopy of mature trees suggest that mortality due to low irradiance may contribute to the decreasing population size of this species. The primary goal of my work was to determine if light and nitrogen fertilization influence the growth and survival of T. baccata seedlings. In 2002 and 2003, we carried out a field experiment with a range of light availabilities (reducing artificial light and obtained 2, 8, 30 and 100% RPPFD -Relative Photosynthetic Photon Flux Density) and a nitrogen fertilization treatment (with and without NH₄NO₃ fertilizer). In 2002 and 2003, the mortality of one-yearold seedlings was very high after the first winter, especially within extreme light conditions (2 and 100% RPPFD). Biomass of seedlings was highest in 30%, intermediate in 100% and lowest in 8% and 2% RPPFD. High levels of seedling mortality during the winter suggest that low temperatures were the primary determinant of T. baccata seedling survival. Nitrogen fertilization only had a positive effect on growth in higher RPPFD values (8, 30 and 100%). Both total needle mass and needle mass allocation were higher in the nitrogen fertilization treatment Interaction of low temperature and light availability is probably the direct reason of high mortality of T. baccata seedlings located near the species range limit.
The results of three-year investigations with cv. Galaxy F1 cabbage grown commercially in an important agricultural region of South Poland are presented. The effect of the rate of ammonium sulphate and UAN (solution of ammonium nitrate + urea), the method of application (placement and broadcast technique) and foliar fertilization (urea and Supervit K) on Cu, Mn, Zn, Fe, B and Mo concentrations in edible parts of cabbage were surveyed. Nitrogen fertilizer was applied at the rate of 120 kg N ha–1. With the placement fertilization method, fertilizer was applied in rows 10 cm deep and 10 cm away from each plant when seedlings were transplanted. Foliar sprayings started at the beginning of intensive leaf growth and continued during the growing season at two-week interval. The foliar nutrition with 2% urea was carried out 3 times and 1% Supervit K was applied once. The field experiment was carried out in 2005-2007 with cv. Galaxy F1 white cabbage on silty clay soil containing 0.91-1.02% organic carbon and soil acidity pHH2O 7.18-8.21 Micronutrient concentrations were below the lower range of the content reported for cabbage grown in non-contaminated areas. Ammonium sulphate significantly increased Mn and Fe concentrations in cabbage heads and decreased B and Mo content. However, the environmental factors considerably modified this tendency. The method of N application affected Mn content in cabbage in 2007 and Mo in 2006 and 2007. Slightly higher manganese and molybdenum concentrations for placement fertilization were noted. In 2005 and 2006, the placement fertilization at the rate of 75% N and supplemented foliar sprays increased Mo content in cabbage.
On the basis of obtained results a de-acidifying compost effect was proved. In the subsequent years, irrespective of the applied fertilization, a declining pH value was registered but also an increasing value of soil hydrolytic acidity. The highest acidification rate occurred in the soil with the mineral treatment. During the three year period of the investigations a decline in the organic C content in soil was noted for each treatment. Generally, by the end of the third year of the studies the total nitrogen content in the soils of individual treatments either remained on a similar level or was higher in relation to the content assessed after the first year. The share of available zinc and manganese forms in total content increased after three years of investigations. No such dependency was registered for copper and zinc. The value of electrolytic conductance in fertilized soil was over twice as high in comparison with the value determined in the control soil. The highest value of this parameter was noted in soil fertilized with farmyard manure. The soil content of phosphorus available forms was on a medium level after the experiment completion, whereas the amount of available potassium forms declined visibly in relation to content assessed in the soil prior to the experiment outset and reached a low level of abundance in the non-fertilized soil and in soil receiving mineral fertilizers.
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