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排序方式: 共有232条查询结果,搜索用时 18 毫秒
91.
Martin Král Martina Ošťádalová Jana Pokorná Bohuslava Tremlová Eliška Rohrerová Marek Šnirc Tomáš Fekete 《Erwerbs-Obstbau》2018,60(1):29-35
This research aims to make an analysis of significant parameters in wine grape from Czech Republic. It was evaluated pH, content of sugar, ascorbic acid, titratable acidity, total phenolic content and texture properties. For analyzes 5 samples of wine grape were used, harvested during the three periods. The results show that during the ripening of wine grapes there were changes of selected qualitative parameters, particularly of total polyphenols, sugar and some varieties of wine grape also ascorbic acid (significantly in the variety ’Grüner Veltliner’, ’Chardonnay’, ’Pinot Blanc’). Pronounced changes qualitative parameters were among wine grapes harvested the 1st and 2nd seasons. Changes in textural properties also occurred during the harvest and for most varieties between 2nd and 3rd period of harvest. The PCA grouped chemical parameters of wine grape in independent sets and can be used as assessment tool of wine cultivars. 相似文献
92.
Marlene Roellig Augusta Costa Matteo Garbarino Jan Hanspach Tibor Hartel Simon Jakobsson Regina Lindborg Sabine Mayr Tobias Plieninger Marek Sammul Anna Varga Joern Fischer 《Strength and Conditioning Journal》2018,71(5):526-535
Europe’s woodland and savanna rangelands, often part of silvopastoral systems known as wood-pastures, are deteriorating because of abandonment that leads to return to a forested state or lack of tree regeneration from overgrazing or tree and shrub removal. Despite numerous local studies, there has been no broader survey of the stand structure of European wood-pastures showing which systems are at risk of losing their semiopen character. This overview aims to 1) show some of the differences and similarities in wood-pastures from landscapes across Europe and 2) identify which of these wood-pastures are at risk of losing their semiopen character. We collated a dataset of 13 693 trees from 390 plots in wood-pastures from eight different European regions (western Estonia, eastern Greece, northern Germany, Hungary, northern Italy, southern Portugal, central Romania, and southern Sweden), including tree diameters at breast height, tree density, management type, and tree species composition. On the basis of their structural characteristics, we classified wood-pastures using principal component analysis (PCA) and cluster analysis. The PCA showed a gradient from dense wood-pastures with high levels of regeneration (e.g., in Estonia) to sparse wood-pastures with large trees but a lack of regeneration (e.g., in Romania). Along this gradient, we identified three main groups of wood-pastures: 1) sparse wood-pastures with mostly big trees; 2) dense wood-pastures composed of small trees, and 3) wood-pastures containing a wide range of tree ages. Our results show a large structural gradient in European wood-pastures, as well as regeneration problems varying in their severity, highlighting the importance of social-ecological context for wood-pasture conditions. To maintain the ecological and cultural integrity of European wood-pastures, we suggest 1) more comprehensively considering them in European policies such as the Common Agricultural Policy and EU Habitats Directive, while 2) taking into account their structural characteristics and social-ecological backgrounds. 相似文献
93.
94.
Jędrysek Mariusz O. Krąpiec Marek Skrzypek Grzegorz Kałużny Adam 《Water, air, and soil pollution》2003,145(1-4):359-375
Water, Air, &; Soil Pollution - Carbon isotope analyses of peat profiles from the Karkonosze Mts. (SW Poland) and tree-ring cellulose from Wis?a river valley in the Kraków region (S... 相似文献
95.
Marek Uliasz 《Water, air, and soil pollution》1988,40(1-2):33-49
A Fourier Amplitude Sensitivity Test (FAST) is applied to study uncertainty of the EMEP-W atmospheric model of long range transport of S in Europe. The FAST method requires frequency distribution of model parameters as input data and provides the following results: (i) mean value of the model output, (ii) variance of the model output which characterizes the parameter uncertainty of the model, and (iii) partial variances of the model output which are the measures of the model sensitivity to uncertainties in individual input parameters. A mathematical formulation of the FAST method and approximations used in its computer implementation is presented. The application requires an extension of the original method to evaluate the model output frequency distribution for different forms of prescribed frequency distributions for parameters. The computer program allows one to apply the FAST method for an arbitrary mathematical model with different options defined by the user. Some examples of uncertainty analysis of the EMEP model using real meteorological and emission data are described and compared with results obtained by the Monte-Carlo method. 相似文献
96.
97.
The study's aim was to analyze the effects of different levels of halloysite (H) and zeolite (Z) in feed and pellets on the growth and meat quality in chickens; 500 Ross 308 broilers were assigned to five groups (1 g, control; 2–5 g, experimental). In Groups 2–5, different proportions of Z and H in feed (25:75 ratio; 0.5% to 2%) and pellet in kg/m2 (2, 0.650H; 3, 0.325H and 0.325Z; 4, 0.650Z; 5, 0.160H and 0.490Z) were used. Body weight was higher than 1 in all experimental groups, and carcass weight was higher, except for Group 2. The feed consumption was lower in Groups 3 and 5 than in Group 4. The breast muscle weight was higher in Group 3 than in the control group. In Groups 2, 3, and 5, the water holding capacity in the breast muscles was better than in Group 4 and in the leg muscles in Groups 3 and 4 than in Groups 1 and 5. Most of the tested characteristics indicate a beneficial effect of aluminosilicates in feed and litter on the growth and quality of meat. 相似文献
98.
Plant cover is an easily discernible, recognisable and labile component of the natural environment that reacts to changes in other components. One of the more important components controlling vegetation cover is the soil, and both vegetation and soil are influenced by topography, amongst other things. As it is in the humus-accumulation horizon of soils that vascular plants have most of their roots, these species are capable of reacting to qualitative and quantitative differences in its composition. The relationship between topography, soil and vegetation were assessed on the basis of three catenal sequences representative of Poland's Wigierski (Lake Wigry) National Park. The aim was to determine if changes in soil along the catenae were reflected in changes in plant community (species richness, species composition, and indicator species). We made use of soil analysis, phytosociological analysis of vegetational structure, and Ellenberg indicator values. Correlations between 23 variables allowed distinguishing 6 statistically-significant groups of variables with main ordinating groups being the percentage shares of species indicating relatively dry, slightly moist soils, the combined shares of these species, altitude above sea level and relative elevation. The first two axes of a Principal Components Analysis were strongly related to soil moisture and elevation (axis 1) and to soil fertility (axis 2). Together, these axes accounted for more than 60% of the variability. Within the forest communities, however, fertility was the most important factor. The three catenae differed most in terms of their species richness and least in soil characteristics. An intermediate place was taken by the weighted Ellenberg's indicator values. The lower sections of catenae were found to have more similarity in terms of soil, vegetation and their interrelationships and patterns than the upper parts. 相似文献
99.
Piotr Brodzki Urszula Lisiecka Adam Brodzki Leszek Krakowski Marek Szczubia Roman Dbrowski Andrzej Junkuszew Mariola Bochniarz 《Animal Science Journal》2020,91(1)
The aim of the study was to evaluate the selected lymphocyte subpopulations TCD4, TCD8, BCD21, BCD25, CD18, CD11b, and MHC II in blood and uterine flush of cows with endometritis, before and after intrauterine (i.u.) administration of cefapirin and methisoprinol. The research was carried out on 28 cows with clinical endometritis. Animals were divided into four groups, each composed of seven cows, depending on the i.u. preparation used: Group A, cefapirin; Group B, methisoprinol; Group C, cefapirin and methisoprinol simultaneously; and a control group—without medication. The study was performed using flow cytometry method. Summarizing the results of the research, i.u. infusion of cefapirin caused a weakening of the effector phase of the local uterine immune response; however, it enhanced leukocyte chemotaxis and antigen presentation. After i.u. administration of methisoprinol, the stimulation of specific uterine immunity mechanisms was mainly observed. The use of both mentioned preparations showed the strengthening of specific uterine immunological mechanisms presumably caused by methisoprinol, despite the inhibitory effect of the antibiotic. Intrauterine use of immunostimulatory substances can improve the effectiveness of the endometritis treatment in cows by improving specific local mechanisms of uterine immunity. As a consequence, it may enhance the effector function of immune competent cells and finally eliminate inflammation. 相似文献
100.
Findoráková Lenka Šestinová Oľga Matik Marek Hančuľák Jozef Bureš Radovan 《Journal of Soils and Sediments》2022,22(9):2448-2458
Journal of Soils and Sediments - To evaluate the ecological risk, physico-chemical properties, and the impact of anthropogenic sources on permanent eighteen samples of grass vegetation soils (PGVS)... 相似文献