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The effect of air temperature on variability of phenophase dates and the length of spring triticale interphases was investigated by means of simple linear regression analysis. An increase in the mean temperature in Poland observed in 1965-2004, the biggest for the mean temperature in August (+0.53°C/10 years, P<0.01) and April (+0.50°C/10 years, P<0.01), caused significant, with P<0.01, acceleration of phenophase dates. The bigger the size of changes, the later the phenophase it concerned – for beginning of tillering the average acceleration of the date amounted to +1.8 day/10 years, for beginning of shooting +3,4 day/10 years, for beginning of heading +4.2 days /10 years, and for wax maturity as many as +10.2 days /10 years. The duration of periods of emergencetillering and tillering-shooting in 1984-2004 became shortened by, respectively, -1.0 day/10 years and –1.5 day/10 years, and the period of heading-wax maturity by –5.9 day/10 years. On the basis of the generalized method of cluster analysis it was determined that the biggest yields of spring triticale crops can be obtained with earlier than average dates from sowing to beginning of heading, and close to average dates of wax maturity and harvesting, and also longer than average interphases: sowing-emergence, emergence-tillering, shooting-heading and periods: sowing-wax maturity and sowing-harvesting, and with close to average duration of periods: heading-wax maturity and wax maturity-harvesting.
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Wymagania termiczne pszenżyta ozimego

100%
Celem pracy było ilościowe określenie wymagań termicznych pszenżyta ozimego oraz wyznaczenie prawdopodobieństwa osiągnięcia dojrzałości woskowej w założonych terminach. W pracy wykorzystano dane dotyczące fenologii pszenżyta ozimego w latach 1982-1996 oraz dane meteorologiczne z 57 stacji IMGW, z lat 1972-2001. Zależności pomiędzy długością międzyfaz a średnią temperaturą powietrza w międzyfazie, a także sumą godzin usłonecznienia bezwzględnego określono za pomocą metody regresji liniowej. Wymagania termiczne pszenżyta ozimego w poszczególnych okresach rozwojowych ustalono metodą sum temperatur efektywnych. Stwierdzono, że pszenżyto ozime osiąga w Polsce dojrzałość woskową, gdy sumy temperatur, liczone powyżej 3°C od momentu trwałego wznowienia wegetacji, wyniosą 1158°C. Prawdopodobieństwo osiągnięcia dojrzałości woskowej przez pszenżyto ozime przed 20 lipca wynosi od poniżej 10% w północno-wschodniej i północno-zachodniej Polsce do ponad 70% na obszarze Niziny Śląskiej. Do 31 lipca pszenżyto osiąga dojrzałość woskową na całym obszarze Polski przynajmniej co drugi rok, a na Niżu Polskim w każdym z 9 na 10 lat.
The goal of the work was to determine which development stages of spring triticale are exposed to the most frequent occurrence of atmospheric drought and also to examine the quantity of reduction in grain yield depending on intensity of drought and a period of its occurrence. Periods of drought were identified through the relative precipitation index (RPI) and the hydrothermal coeffi cient K. The research used data from 34 experimental stations of the Research Centre for Cultivar Testing (COBORU), situated in whole Poland, encompassing the dates of sowing, emergence, tillering, shooting, heading, wax maturity and harvesting, and spring triticale grain yield in the years 1984–2004 as well as meteorological data, average air temperature and atmospheric precipitation total, from stations of the Institute of Meteorology and Water Management (IMGW) located in the vicinity of experimental stations. The results concerned a standard of spring triticale determined as an average of varieties cultivated in a given year. It was stated that periods of drought of various intensity most frequently occur in spring in the period from sowing to tillering. Spring triticale endures dry periods well (50 < RPI < 74% or 75 < RPI < 89% of the norm; 0.4 < K ≤ 1.0), and the highest reduction in the quantity of spring triticale grain yield is caused by very and extremely dry conditions in the period from heading to wax maturity as well as in the whole period from sowing to wax maturity.
Cucumber cultivation in Poland is connected with a certain climatic risk, producing small yields of the plant. Selection of areas suitable for cucumber cultivation should be based not only on soil conditions and agrotechnical recommendations, but also on knowledge of the rate of growth and development of the plant. The aim of this work was to determine the effect of solar conditions and the thermal conditions of air on the variability of cucumber developmental stages in Poland from 1966–2005. To achieve the goals, data was collected from 28 experimental stations of the Research Centre for Cultivar Testing (RCCT) and 50 meteorological stations of the Institute of Meteorology and Water Management (IMWM) concerning respectively: the duration of cucumber development stages and sunshine duration and air temperature from 1966–2005. The relationship between the duration of developmental stages and the examined meteorological elements was determined by analysis of linear and second degree polynomial regression and thermal requirements of the cucumber in the period from sowing to the beginning of fruit setting, determined by means of the effective temperature sum method. Results obtained in this work may be used, for example, in the process of adjusting field production of cucumbers to changing climatic conditions in Poland.
The aim of the work was to assess the temporal distribution of NO2 and NOx concentration in relation to wind direction and to determine the effect of major meteorological elements on the size of NO2 and NOx concentration in northwest Poland. In the area of the research, in the period from 1st May 2005 to 30th April 2007 the highest average concentration of NO2 and NOx, both during cold and warm half-years, occurred with southeasterly wind, and the lowest with south-westerly wind for NO2 and with north-easterly wind for NOx. The highest determination coeffi cients and, at the same time, the smallest estimation errors for multiple regression equations, describing the dependence of the concentration of NO2 and NOx from meteorological elements, were obtained with westerly wind in the cold half-year and with south-westerly wind in the warm half-year.
The aim of the studies was to determine relationships between the concentration of nitrogen dioxide and sulphur dioxide in the countryside area and the selected meteorological elements. In the studies the data concerning the immission of gas pollution and meteorological data were taken into account and they were gathered, respectively, at the station monitoring the air quality and the agrometeorological station of Agricultural University of Szczecin, situated in the middle part of Szczecin Lowland (in Lipnik, near Stargard Szczeciński) in 1998–2005. In the countryside area of Szczecin Lowland the time distribution of the NO2 and SO2 concentrations did not show a distinct seasonal structure. During the seasonal heating the amount of the SO2 immission was the same as during the summer. In 1998–2005 the improvement of the air quality in Szczecin Lowland resulted from a decreasing tendency of the SO2 concentration during all the months of the year and a decreasing tendency of the NO2 concentration in August and September. In the set of meteorological elements, the most strongly correlated with concentrations of the two gas pollution factors and of the strongest role were the average speed of wind, the atmospheric pressure and the maximum air temperature.
The aim of the work was to assess the changeability of concentrations of nitrogen dioxide, sulphur dioxide and suspended dust PM10 in an urban area of Suwałki depending on selected meteorological elements. The work takes into account daily data concerning the ambient concentration of gas and particulate pollutants and meteorological data from the station of air quality monitoring and the Institute of Meteorology and Water Management (IMGW) in Suwałki in 1994-2003. In Suwałki, time distribution of SO₂ and PM10 in contrast with NO₂ showed a distinct seasonal structure. In a heating season the ambient concentrations of SO₂ and PM10 were considerably higher than in the summer. The deterioration of air quality in Suwałki resulted from an upward tendency of NO₂, SO₂ and PM10 concentrations in 1994-2003, with exception of the period from May to July when the dust showed a considerable downward tendency. The biggest number of significant relations between gas and particulate pollutants and meteorological elements were shown in a heating season, especially in January and December, the least in the summer, in July and September. In climate conditions of north-east Poland the following elements were unfavourable to air cleanliness: wind velocity below 2.2 and 1.9 m s⁻¹ for NO₂, for a heating and summer season respectively, average air temperature in a heating season below -2.0°C for SO₂, wind velocity below 1.8 and 1.6 m s⁻¹ for suspended dust PM10, for a heating and summer season respectively.
The goal of the work was to assess precipitation conditions in the Polish zone of the South-Baltic Coastland taking into consideration multi-annual variability. Meteorological data from 8 stations of the Institute of Meteorology and Water Management (IMGW) situated in the Polish zone of the South-Baltic Coastland covering seasonal and yearly atmospheric precipitation totals in 1963–2007 constituted the material for the research. Precipitation was classifi ed on the basis of the standardized precipitation index (SPI). The lowest total precipitation occurred in the vicinity of the Szczecin Lagoon, the Pomeranian Bay and the Gdańsk Bay, the largest precipitation was observed on the Koszalińskie Coastland. In the Polish zone of the South-Baltic Coastland one can observe the prevalence of frequency of moderately wet and severely wet seasons, compared to moderately dry and severely dry seasons. On the other hand, during half of the seasons extremely dry conditions occur more often than extremely wet conditions. The only signifi cant trend, a positive one, was statistically confi rmed for the yearly precipitation total in Resko; and the signifi cant positive trends for the seasonal precipitation total – in Świnoujście and Szczecin in summer, in Gdańsk – in spring and in Elbląg, Koszalin and Resko – in winter.
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