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A major problem in the quantitative hydrological studies, especially fl uvial, might be dealing with assessment of methods and results basing on error analyses. As for the mountain and Upland Rivers, the most common source of the errors could be low frequency of measurements and collection of samples. These particular studies have been carried out for the 8 sectors (sub-catchments) of the Silnica and Sufraganiec catchments of different use. The urban catchments of the river Silnica has been spread over 49.40 km2, and agricultural-woodland catchments of Sufraganiec has embraced 62.01 km2. During 11 high rivers’ stands, of variable origin, a few parameters have been determined, i.e. single unit outfl ow, concentration of suspended matter, concentration of dissolved matter, and temperature of the river waters every hours for the summer months and every two hours for the winter months. All the daily values of the above mentioned parameters have been compared with those values at 7 o’clock every day, and calculated mean values for the particular high rivers’ stand. Maximum error for the values of single unit outfl ow has been highly variable compare to the other values, being in the range of 65.4 to 873%. The highest spatial variability of the mean error of the measurements has been observed during high rivers’ stands related to the convection rains, whereas the smallest spatial variability of that error has been noted during high rivers’ stands due to widespread rains. The highest error while assessing our results has been found at the end of the urban catchments (Pakosz, Białogon). Maximum error for the concentration of the suspended matter has changed from 83.6 to 604.5%. Similarly, maximum error for the concentration of the dissolved matter has changed from 80.9 to 132.2%, whereas mean values have shown an error of 98.5 to 101.7%. All the observations have led to a conclusion that error for all the determined values is directly related to the space modifi ed anthropogenically. If that space increases, the error for measuring parameters of the fl uvial transport increases too. It means, that only high frequency of fi eld measurements of the fl uvial transport could reduce the errors while determining parameters of the transport. Ideally, more or less continuous measurements could reveal some complex mechanisms of fl uvial transport.
As a result of enlarging the depth of exploitation of raw rock material deposits of marl and limestone at Leśnica-Małogoszcz (Przedborsko- Małogoskie Range – Świętokrzyskie Voivodeship), initially to the level of +215 m a.s.l. and then +200 m a.s.l., a mine depression cone will develop, which may threaten the existence of wetlands included in the Natura 2000 network. The wetlands are present in the pre-gorge section of Łososina river flowing through Grząby Bolmińskie and Gnieździskie Hills, at the mouth section of its hydrometrically ungauged tributary – the Wrzosówka river. In the study there has been demonstrated the possibility of preserving the current state of moisture content of the habitats which exist here, taking into account the quantitative characteristics of the components of water cycle and morphological conditions. The analysis of water resources has shown that under the conditions of a functioning mine depression cone, they will be sufficient to supply endangered wetlands and enable their irrigation. The solutions of an ecohydrological character have also been put forward which would compensate the loss of water in the area within the open-pit mine depression cone. This would require the construction of dams (e.g. artifi cial rapids) in the Wrzosówka river bed and a system of ditches at the bottom of its valley.
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