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51.
Assessment of the usefulness of particle size distribution measured by laser diffraction for soil water retention modelling
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Krzysztof Lamorski Andrzej Bieganowski Magdalena Ryżak Agata Sochan Cezary Sławiński Wioleta Stelmach 《植物养料与土壤学杂志》2014,177(5):803-813
Particle size distribution (PSD) is a major soil characteristic, which is essential and commonly used for the development of pedotransfer functions (PTFs) to estimate the water retention of soils. The laser diffraction method (LDM) became a popular alternative to the standard sieve‐hydrometer method (SHM) of PSD measurement. Unfortunately, PSDs determined with LDM and SHM methods differ sometimes substantially. Moreover, it is claimed that the laser diffraction method underestimates finer fractions in favor of coarser fractions. Several authors have tried to elaborate on methods to recalculate LDM PSD into its SHM counterparts, but no universal methodology has been developed to this date. In this paper, we use PSD determined by LDM directly for PTF development and compare it with the classical PTF approach based on PSD measured by SHM. Four different PTF models based on LDM particle size distribution data were developed, with different PSD characteristics taken as the models' input variables. The possibility of using alternative PSD characteristics, such as deciles, area moment mean and volume moment mean, for PTF development was examined. The accuracy of PTF models constructed on the basis of LDM‐measured PSD was comparable with that of the developed models using texture data obtained from SHM, giving approximately the same RMSE and R2 values. Our study shows that LDM‐measured particle size distribution may be directly used for PTF developments without any recalculations to their sieve‐hydrometer counterparts. 相似文献
52.
Masternak Katarzyna Oko Sylwia Kamola Marek Ociepa Tomasz Nucia Aleksandra Kowalczyk Krzysztof 《European Journal of Forest Research》2022,141(4):617-628
European Journal of Forest Research - Increasing areas of gradation, making it difficult or impossible to perform restorations and forestations, and as causing tree crown damage, result in the need... 相似文献
53.
Bukowski R Szalewicz K Groenenboom GC van der Avoird A 《Science (New York, N.Y.)》2007,315(5816):1249-1252
A force field for water has been developed entirely from first principles, without any fitting to experimental data. It contains both pairwise and many-body interactions. This force field predicts the properties of the water dimer and of liquid water in excellent agreement with experiments, a previously elusive objective. Precise knowledge of the intermolecular interactions in water will facilitate a better understanding of this ubiquitous substance. 相似文献
54.
Magdalena Niedzia?kowska W?odzimierz J?drzejewski Sabina Nowak Krzysztof Schmidt 《Biological conservation》2006,133(1):63-69
Based on data from the National Lynx Census, carried out in Poland in 2000-2001, and using Geographic Information System, we analysed nine habitat characteristics in 56 circular sample plots (113 km2 each), where lynx (Lynx lynx) have been recorded, and 118 plots with no signs of their presence. In plots with lynx the forest cover (on average 68%) was two times higher and the forest fragmentation lower than in plots with no lynx records. The plots with and without lynx differed significantly also in the number of villages and towns, length of main motorways and railways. Lynx occurrence was negatively associated to human settlements and transportation infrastructure. Logistic regression analysis showed that sufficient forest cover (>40%) and the short straight-line distance to the eastern or southern border of Poland (as a proxy of the distance to a more contiguous range of lynx in Europe) are the two most important variables explaining lynx distribution. We conclude that, in Poland, increase of forest fragmentation and transportation infrastructure may become important threats to lynx populations. 相似文献
55.
Krzysztof Różyło Edward Pałys 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):260-266
Full exploitation of the potential of new varieties requires research, whose aim is to adapt the technology to their needs. A two-factor experiment evaluated the effect of row spacing (33, 44, and 55 cm) of three oilseed rape (OSR) varieties (conventional, hybrid, and “semi-dwarf” hybrid variety) on canopy area index (CAI) and yield components. At higher row spacing, OSR plants were characterized by a strong increase in the CAI at successive growth stages; thereby, the incomplete use of production area was compensated at the pod development stage. The differences in the CAI between row spacings were significant until the end of flowering, whereas differences in the CAI between varieties were significant until the flower bud development stage. In the next development phases, CAI of OSR plants was at a similar level to all plots. However, the statistical analysis showed a declining trend in seed yield and yield biomass (pods and straw weight) with increasing row spacing. A positive aspect of increased row spacing was a decrease in glucosinolates content in seeds. The differences in fat content were statistically insignificant. The hybrid varieties of OSR produced the highest seed yield at a row spacing of 33 cm, while the conventional – at a row spacing of 44 cm. These relationships are confirmed by high positive correlations of seed weight and pod weight per unit area with CAI. The results have important practical aspect, because it shows that it is possible to reduce the number of OSR plants per unit area, thereby reducing demand for expensive certified seeds for sowing but to certain limits. Too small plant density binds to the risk of decreased seed yield. It may be justified, e.g., in extensive or organic farming where wide row creates the possibility of mechanical weed control. 相似文献
56.
Krzysztof Saja 《Agriculture and Human Values》2013,30(2):193-202
Most ethical discussions about diet are focused on the justification of specific kinds of products rather than an individual assessment of the moral footprint of eating products of certain animal species. This way of thinking is represented in the typical division of four dietary attitudes. There are vegans, vegetarians, welfarists and ordinary meat-eaters. However, the common “all or nothing” discussions between meat-eaters, vegans and vegetarians bypass very important factors in assessing dietary habits. I argue that if we want to discover a properly assessed moral footprint of animal products, we should take into consideration not only life quality of animals during farming or violation of their rights—as is typically done—but, most of all, their body weight, life time in farms and time efficiency in animal products acquisition. Without these factors, an assessment of animal products is much too simplified. If we assume some easily accepted premises, we can justify a thesis that, regardless of the treatment of animals during farming and slaughtering, for example, eating chicken can be 163 times morally worse than eating beef, drinking milk can be 58 times morally better than eating eggs, and eating some types of fish can be even 501 times worse than eating beef. In order to justify such a thesis there is no need to reform common morality by, for example, criticizing its speciesism. The thesis that some animal products are much worse than others can be justified on common moral grounds. 相似文献
57.
Krzysztof Kołodziejczyk Monika Kosmala Joanna Milala Michał Sójka Małgorzata Uczciwek Bogusław Król 《The Journal of Horticultural Science and Biotechnology》2013,88(6):89-95
SummaryPomaces obtained during the production of cloudy or clear juice from scab-resistant apple cultivars (28 harvested in 2006, and 23 harvested in 2007) were studied as a source of nutritionally important components. It was shown that the average yield of pomace during the production of cloudy juice was 6.4% (w/w), and 4.9% (w/w) for clear juice pressing. The average total dietary fibre (TDF) contents were 48.4% (w/w) and 52.4% (w/w) for cloudy and clear juice pomaces, respectively. Ten pomaces from cloudy apple juice production, and 12 obtained from clear juice production, contained ≥ 2,000 mg kg?1 of polyphenols.‘Ariwa’ and ‘Rajka’ are apple cultivars suitable for juice production and their pomaces are characterised by having high contents of TDF [50.9% (w/w) and 51.1% (w/w), respectively], with aboveaverage polyphenol and quercetin glycoside concentrations. The mean contents of quercetin glycosides for pomaces from all apple cultivars was 994 mg kg?1 after clear juice production, and 908.2 mg kg?1 after cloudy juice production. ‘Topaz’, which became a popular commercial apple cultivar in Europe, was the best source of health-promoting components. Its pomace was the richest source of polyphenols among all 28 cultivars studied. It contained ≥ 2,000 mg kg?1 quercetin glycosides in both its clear and cloudy juice pomaces. 相似文献
58.
Krawczyk Krzysztof Uszczyńska-Ratajczak Barbara Majewska Alicja Borodynko-Filas Natasza 《植物病害和植物保护杂志》2017,124(6):577-583
Journal of Plant Diseases and Protection - We describe the construction and evaluation of DNA microarray for simultaneous detection and identification of five microbial pathogens of maize: Pantoea... 相似文献
59.
Aleksandra Bawiec Katarzyna Pawęska Krzysztof Pulikowski Joanna Kajewska-Szkudlarek 《Water, air, and soil pollution》2018,229(7):232
The use of plants and natural processes for wastewater treatment is an issue that arouses interest among technologists and scientists around the world. The aim of the article was to analyze the influence of the air temperature and insolation on the removal of nitrate nitrogen from the wastewater treated in the hydroponic system, under greenhouse conditions. Samples of sewage for its quality tests were taken from a wastewater treatment plant (WWTP) located in the southwestern part of Poland. Data regarding daily sunshine duration and average daily air temperature values in selected periods of 2013–2016 come from a meteorological station located 30 km from WWTP. The conducted research and analyses of the results clearly indicate that under moderate climate conditions, the amount of solar radiation reaching the Earth’s surface is insufficient to ensure the year-round, effective wastewater treatment process in the hydroponic system. In the case of air temperature, no correlation was found between the tested parameters, which indicates the lack of temperature influence on the efficiency of NO3 removal from the wastewater by macrophytes growing in the lagoon. 相似文献
60.
Andrzej Węgiel Stanisław Małek Ernest Bielinis Donald L. Grebner Krzysztof Polowy Joanna Skonieczna 《Scandinavian Journal of Forest Research》2018,33(3):261-270
Increasing demand for renewable energy and limiting CO2 emissions have stimulated much interest in wood-based biofuels. Unfortunately, expanding the utilization of forest biomass may cause nutrient depletion in forested environments. This study investigates the element content from various parts of the tree. Comparisons were made between different harvesting scenarios and their impact on the amount of nutrients removed from the forest environment. The harvesting scenarios were: stem-only harvesting (SOH), branch and stem harvesting (BSH), and two variants of whole-tree harvesting (WTH). The elements taken into account were: carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulphur (S), copper (Cu), iron (Fe), nickel (Ni), manganese (Mn), zinc (Zn), cadmium (Cd), chromium (Cr) and lead (Pb). To make the results comparable, the same amount of removed biomass was taken into calculation. The differences between harvesting scenarios were significant. The amounts of removed elements formed similar pattern: the lowest level was found in SOH, average in BSH, and highest in both variants of WTH. This confirms that the application of WTH is connected with increased risk of nutrient depletion, even when the volume of harvest would be equal to other variants. 相似文献