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  • Author: Agnieszka Strzelczak x
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Bathymetric measurements of Morskie Oko Lake

Bathymetric measurements of Morskie Oko Lake

The aim of this study was to gather and summarize bathymetric measurements of Morskie Oko Lake which have been carried out up to now. Apart from the two existing plans from 1909 and 1934, a plan presenting the arrangement of isobaths in 1879 was worked out on the basis of numerical data. Moreover, after field investigation with an echo sounder in 2011, a new bathymetric plan was created. All four plans were used to calculate the basic morphometric parameters of Morskie Oko. Bathygraphic curves were determined from the volume of water found by measuring the areas between consecutive isobaths. The least accurate data come from 1879 while there is a considerable resemblance between the plans dated to 1934 and 2011. In case of the most recent plan, the measurements were for the first time related to the average, multi-annual (1963-2010) water level. Thus, the greatest depth found in 2011 can be regarded as the maximum depth. Further bathymetric studies could help to determine the rate of shallowing of Morskie Oko lake caused by weathered rock material, transported for instance by avalanches.

Open access
Application of artificial neural nerworks in oxidation kinetic analysis of nanocomposites

Application of artificial neural nerworks in oxidation kinetic analysis of nanocomposites

This study concerns the application of artificial neural networks in oxidation kinetic analysis of ceramic nanocomposites. The oxidation of the Ti-Si-C ceramic nanocomposite in dry air was studied. The size of the nanoparticles was determined by scanning electron microscopy (SEM). The gaseous oxidation products were analysed by mass spectroscopy (MS) while the solid oxidation products by X-ray diffraction (XRD). The kinetic analysis of the oxidation was based on the Coats-Redfern equation. The kinetic models were identified for the consecutive stages and then the A and E parameters of the Arrhenius equations were evaluated. Artificial neural networks were used at each step of the kinetic calculations.

Open access
Examples of lake disappearance as an effect of reclamation works in Poland

Abstract

Glacial lakes undergo evolution with their disappearance as the last stage of it. Natural processes which determine the rate of lake shrinking occur rather slowly but they have been increasing their speed with the stronger human interference in the environment. The most drastic effect of anthropogenic pressure exerted on lake ecosystems is their complete disappearance caused by reclamation works. One can state that this process is a change of rapid character (a lake can disappear within a few years or several decades, in extreme cases even within one year). Drainage works are particularly unfavourable in areas with a shortage of water supplies, where rapid lake shallowing reduces water retention even more. A considerable part of Poland suffers from water supply deficiency. Therefore, draining of lakes should be considered as an adverse operation. This study discusses the examples of eleven lakes located in Poland and subjected to reclamation works. Analyses of those cases lead us to the conclusion that drainage aiming to broaden agricultural areas has not always been proper.

Open access