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Study of meadow grass biology were started already in the thirties. After the second world war number and range such kind of studies had increased systematically and their methodology had been improved. The studies were carried out in the control conditions and as field experiments, in pure stands and in mixtures, in specialist as well as in practical experiments. The results obtained have allowed to explain many occurrences which took place in the applied studies and they affected improvement of rational management of grassland and helped in valorisation and characterisation many of grass species. Continuation of grass biology studies is necessary but in complex way and in co-operation with different branches of basic sciences using modern equipment and unify methods of studies.
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The aim of this study is to analyse economic aspects of the utilisation of complementary seeding for the renovation of grasslands. The paper presents results of our own investigations but also uses literature data to perform appropriate calculations. It appears that complementary seeding is a method of grassland renovation recommendable from the point of view of economy since the value of the ratio of the cost of production of 1 MJ feed energy to the value of its upgrading in animal production is at the level of 1.2-1.5. In comparison with the method of conventional tillage, complementary seeding is by 54- 62% cheaper, depending on the applied technological solutions. When calculating profitability of complementary seeding in grassland renovation, it seems more rational to apply the method which - for calculation purposes - takes into consideration the duration of the effect of complementary seeding expressed by the persistence of introduced species. From the economical point of view, complementary seeding should be considered as effective if the cost of the surplus of 1 dt of dry matter, 1 MJ energy or 1 kg protein obtained in the result of complementary seeding of grassland is lower than the unit cost of production of dry matter, energy or protein from sward which was not subjected to the treatment. Renovation of grassland by overdrilling, especially when performed with the aid of special seeders which increase - in comparison with traditional methods - effectiveness of yield improvement and sward quality, allows to decrease the profitability threshold of milk production. The use of complementary seeding in pratotechnique increases economic effectiveness of feeds from grasslands and, in addition - thanks to its proecological character, barely interfering in the meadow habitat - it allows to take multifaceted economic advantage from the entire natural environment. The economical aspects of complementary seeding application in grassland renovation requires further research.
The aim of the work was the determination of the effect of the bed salinisation and alkalisation on germination and seedlings development of 8 basic turfgrasses. Bed was light soil, rate of salinisation was based on electrolitical conductivity (<4 mS cm⁻¹, 4-8 mS cm⁻¹, > 16 mS cm⁻¹) and ash from „Siekierki" Heating Plant. The results shows, that salinisation at the level 4-8 mS cm⁻¹ did not cause evident disturhances in germination of cultivars Nimba and Leo Festuca rubra, Nigra and Nira Lolium perenne and Igeka Agrostis capillaris. salinisation over 8 mS cm⁻¹ only cultivar Nimba Festuca rubra. The process of germination was effccted at lower degree of ash alkalinity than its salinisation. Alkaline pH significantly effected plant growth, especially roots.
The present studies concerned 21 cultivars of 7 lawn grass species (Agrostis canina L., Agrostis capillaris L., Festuca heterophylla Lam., Festuca ovina L. sensu lato, Festuca rubra L. sensu lato, Lolium perenne L., Poa pratensis L.) and Festuca arundinacea Schreb. Two sowing dates were applied: spring and late summer. Six to ten cuttings were made during the vegetation periods in the years of full utilisation. The rate of re-growing after cutting was evaluated on the basis of plant height before each of the following cutting. All Poa pratensis cultivars and Agrostis genus species characterized by the slowest re-groving rate after cutting. Among the remaining cultivars Niko (Festuca ovina), Nimba (Festuca rubra), Sawa (Festuca heterophylla) and Stadion (Lolium perenne) showed slow rate of re-growth. Cultivars of studied species (except from cultivars of Agrostis genus) sown in the spring were higher before each cutting than those sown in late summer.
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Paper reviews the study results obtained by many authors complementary seeding. Presented results entirely confirmed of complementary seeding to improvement of meadows productivity in various site conditions. Habitat conditions decide about succeeding of complementary seeding to a considerable degree. Most important condition is a water, especially soil sufficient humidity in seeds germination and seedling growth time. Immediate relation with that have the rainfalls, especially in dry sites. Important condition is also type of soil and it's trophicity. The divergence received in numerous studies has source in variety of habitats, great number of complementary seeding realisation techniques, likewise in typical plenty of improved meadow-grazing sward and also species used to complementary seeding.
Rys historyczny problematyki torfowisk w Polsce. Trudności i drogi postępu. Dawne i współczesne osiągnięcia ze szczególnym uwzględnieniem dorobku Zakładu Doświadczalnego Instytutu Melioracji i Użytków Zielonych – Biebrza
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People are interested in the possibility of renovation of degraded grasslands since a long time. More intensive studies on this subject were performed in 1920-1939, mostly are to the activity of scientist from Experimental Research Institute in Sarny. Next growth of the interest in application of complementary seeding methods in pastures and meadows takes place after 1945 years. These studies included an estimation of farming tools (tooth harrow, disk harrow and rototiller). Experiments give different effects of complementary seeding. Authors of particular papers underlined the fact that the efficiency of various tools and machines depend on the communities conditions and the botanical composition of swards. As the chemical industry developed so herbicides are more after used in reseeding experiments. The feelings on usefulness of application of herbicides controversial. From the beginning of 80-ties of this century the studies are developing, in which special drill for sod seeding are used. It follows from results published that such method of renovation of degraded grasslands should be extensively practised. Overdrilling is easy performed and besides, expenses are in this case significantly lower then these connected with the use of other methods.
Rys historyczny powstania i rozwoju polskiego łąkarstwa i jego zależności i związków z melioracjami wodnymi. Podsumowanie i wnioski wskazujące na znaczne osiągnięcia w obu dziedzinach. Przegląd literatury tematu.
Na łące, w której składzie botanicznym wyczyniec łąkowy stanowił ponad 50%, porównywano wpływ dwu-, trzy-, i czterokrotnego koszenia na skład runi oraz na wielkość plonu i jego wartość żywieniową. Przedstawiono też względny koszt zbioru siana przy różnej częstotliwości koszenia.
Na podstawie literatury i prac własnych scharakteryzowano przydatność wybranych gatunków i odmian traw jako komponentów do mieszanek na pastwiska trwale i przemienne. Wyróżniono pod względem wczesności trzy grupy gatunków i odmian: wczesne, średniowczesne i późne. Opracowano skład 15 mieszanek: 9 na pastwiska trwałe i 6 na przemienne.
Podsiewy na pastwiskach kośnych stanowią alternatywę dla ich odnawiania poprzez zasiew, tak pod względem ekonomicznym jak i ekologicznym. Pozytywnemu efektowi podsiewu zagrażają w dużym stopniu susza po jego wykonaniu oraz opóźnione użytkowanie. Podsiewy można planować elastycznie. Istnieje duża możliwość dopasowania ich do aktulnych warunków. Ze względu na statystycznie udowodniony pozytywny wpływ podsiewów na jakość paszy łącznie z jej zdolnością do konserwacji, plon i lepsze wykorzystanie składników pokarmowych, stanowią one, pod warunkiem ich starannego wykonania, cenny instrument regulacyjny w gospodarstwie. W przeciwieństwie do pastwisk i pastwisk kośnych istnieje jeszcze duże zapotrzebowanie na badania nad podsiewami dla wyraźnego polepszenia jakości łąk.
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