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The aim of the study was to estimate the frequency and strength of storm surges in the Oder River mouth area during the 1993/94–2016/17 seasons. The analyses involved water level readings recorded at gauges located in the Oder River mouth area, including the coasts of the Pomeranian Bay (Zatoka Pomorska) and the Szczecin Lagoon (Zalew Szczeciński), as well as the downstream reach of the Oder. Recognition of temporal and spatial water level variations in the region under investigation revealed signicant irregularities in storm surge occurrence; periods with an increased frequency of surges followed long periods with their scant occurrence. During the year, most of the storm events were observed between November and January. In the period discussed, the most severe and extensive storm surge in the Oder River mouth area was observed in October 2009. Very high surges were recorded in November 1995, January 2012, and January 2017. The long-lasting and extensive high water events in the downstream reach of Oder River resulted from the progressive and prolonged increase in sea level in the Pomeranian Bay. Long-term persistence of high water levels in the Oder River mouth area were also registered when storm surges limited the outflow of the Oder River during snow-melt events, ice jams developing on the lower Oder at the same time. Finally, severe storm events were observed under the condition of the increased water volume in the Baltic Sea.
Within the framework of the research described here, an attempt was made to identify volatile and semivolatile Non-Regulated Organic Compounds present in samples of riverine water. Twenty-five samples, collected from the Odra River during the eighth sample collection in October 2000 within the framework of the International Odra Project, have been analyzed using the PT-TD-GC-MS technique. A computerized analysis with the use of a mass spectrometer pointed to the presence of organic compounds of natural and anthropogenic origin. The concentrations of chloroorganic compounds, i.e. saturated and unsaturated aliphatic aromatic hydrocarbons and chlorinated bis-isopropyl ether, in samples of water collected near Brzeg Dolny amounted to about 1 ppb. A slightly narrower spectrum of chloroorganic compounds occurring at lower concentrations was identified in samples of water collected in Głogów. The most likely source of these compounds was the “Rokita” Chemical Plant.
Flooding in East-Central Europe in May and June 2010 also affected the Odra River Basin. Unlike a typical summer flood scenario, in 2010 intensive precipitation was observed as early as May. Also, the location of the most intensive rainfall shifted to the catchments of the right bank tributaries of the Odra River. This paper presents the climatological assessment of the precipitation totals that caused two flood waves on the Odra River. The assessment was carried out with the use of selected indicators: monthly precipitation totals, daily precipitation totals, number of days exceeding given precipitation levels, number of days with precipitation of a given probability of exceedance and intensity, duration and accumulation of precipitation for a number of consecutive wet days. The reference values for climatological indicators were developed for the period 1966-2009. The values of the selected indicators were analyzed in terms of flood hazard in relation to the hazard gradation. The results show that the observed precipitation had the character of an extreme event with respect to its magnitude, duration and spatial extent. The catchments with recognized high levels of flood hazard were affected by the flood wave. The flood situation caused by the extreme precipitation was evaluated in the context of the largest floods in this region during recent decades.
Comparison of phytoplankton composition from selected sites in the lower Odra River was done to determine whether the effects of heated water are strongest, from the considered environmental factors. Samples of phytoplankton were collected in April, July and October 2009–2011 at five sites along the lower section of the Odra River. The most pronounced differences between the phytoplankton at the sites were revealed in the phytoplankton abundance and they were related to the time of water retention, the washing out of plankters from slack waters, and the predation by molluscs and zooplankton. The strongest correlations were found between the phytoplankton abundance, the content of inorganic nutrients and temperature. Taxonomic composition of phytoplankton at all sites in the same months was similar. Cooling water from the power plant seems to accelerate eutrophication in the discharge but has no significant impact on the phytoplankton composition downstream in the Odra River.
This paper presents the results of polychlorinated biphenyls (PCBs) determination in sediments from different sites of the Odra River and its tributaries, collected in 1998-2002. It was found that concentrations of PCBs varied significantly. The results of individual congeners show that contents of PCBs 180 and 138 were the highest in the sediments investigated. For better identification of places most polluted by PCBs, PCB contents on TOC (total organic carbon) basis in surface sediments are presented.
This paper describes the application of artificial neural networks (ANNs) for the time series modeling of total phosphorous concentrations in the Odra River. Data from the monitoring site Police in the lower part of the Odra were used for training, validating and testing the models. Two models are proposed to prove the satisfactory forecast of phosphorus concentrations: a simpler one with a single input variable and a more complex one with 14 input variables. Both ANN models show a high ability to predict from the new data set. On the basis of sensitivity analysis the relationships between phosphorus concentrations and other water quality variables were established.
During the 2010 flood in the Odra basin a measuring campaign was executed that produced a set of data on peak discharges. Flow measurements located near gauging stations were taken from a boat with an Acoustic Doppler Current Profiler (ADCP) equipped with a GPS. The paper presents a detailed analysis of the records, including referencing to ortophotomaps, to assess the quality of ADCP recording, local flow characteristics and finally to re-evaluate the total discharge values. Further, the flow is divided between the main channel and the floodplains, while the main channel in the case of the presence of groynes is additionally divided into a central zone between the groynes and zones of groynes. Partitioning of particular zones to the total discharge is calculated along with average and maximum local flow velocities. The study delivers data for the development of more reliable numerical modelling tools, which in turn may fulfil the measuring gaps in situ. It is shown that the modern field data acquisition GIS post processing, and numerical modelling support each other and improve the final overall result, bringing hydrologic products to a higher standard. The synergy of hydraulics and geoinformatics in hydrology is therefore highly recommendable.
This article describes the changes in the land cover and management of floodplains in towns located on Poland’s Oder River, estimates flood risk and how it has been changing in these towns, and how these changes have affected the environment. The paper also includes an analysis of trends in floodplain management defined in local planning documents. The research was conducted for the period of 1995-2010 and included two towns: Kostrzyn on the Oder and Krosno Odrzańskie. The former lies in the lower course of the Oder and the latter in its middle section. The research indicates that flood risk has risen due to the continuous development of urbanized areas (both unbuilt and built-up) that used to be exploited as arable land. That had a negative effect on the environment, as well.
This paper gives a general overview of Polish experience and achievements with regard to hydrodynamic modelling in the Polish zone of the Baltic Sea. The first work started already at the end of the sixties when the first 1D and 2D hydrodynamic models were set up. With the development of numerical methods and increasing computational power a number of 1D, 2D and 3D models were set up and tested. Global, regional and local models cover the most important water bodies, i.e. the Pomeranian Bay – Szczecin Lagoon and Gulf of Gdańsk – Vistula Lagoon systems.
The Odra is the second largest river in Poland, running from the Czech Republic through a large part of Poland before entering the Baltic Sea. Its catchment area has been heavily polluted by anthropogenic emissions. Our data document an intensive anthropogenic impact on the abundance of heavy metals in bottom sediments of the middle part of the Odra. Normalized heavy metal concentrations in sediments and indices of geoaccumulation (Igeo) indicate that this area is polluted by various metals, especially mercury, cadmium and zinc. The ranges of their concentrations vary as follows: Hg 0.12-2.99 mg/kg, Cd 2.93-7.87 mg/kg, Pb 21.2-163 mg/kg, Cu 11.5-88.3 mg/kg, Zn 28.0-471 mg/kg, Cr 1.57-47.5 mg/kg, Ni 5.10-19.1 mg/kg, Fe 1493-37972 mg/kg and Mn 47.6-1242 mg/kg.
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