Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 7

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

Assessing spectral indices for detecting vegetative overgrowth of reservoirs

100%
Jaskula J., Sojka M.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 6
2

Analysis of degradation processes in reservoirs based on remote sensing data

100%
Jaskula J., Sojka M.
Acta Scientiarum Polonorum. Formatio Circumiectus
|
2019
|
tom 18
|
nr 2
Aim of the study The primary objective was to assess spatio-temporal changes of the vegetation occurring in 12 reservoirs located in the Odra River basin. The analysis was made for reservoirs of different constructions, i.e. single stage, two-stage and lateral. The second purpose was to analyze possibility using remote sensing data to monitor the dynamics of the vegetation processes. Material and methods Monitoring and mapping of spatio-temporal changes of the vegetation occurring in the reservoirs was analyzed on the basis on Sentinel-2 data. The analysis was based on the NDVI and the WAVI indices. To specify spatial changes of vegetation, the reservoirs were split into zones equals to 250 m. The statistical analysis was aimed at comparing the NDVI and the WAVI values between designated zones. In turn, Cluster analysis (CA) was used to group reservoirs into clusters on the basis of similarities between the NDVI and the WAVI values. Results and conclusions Cluster analysis (CA) showed that each reservoir is separate water body where decisive impact on degradation process could have different factor. There was observed that two-stage construction focuses degradation processes in pre-reservoir and protect water resources in the main part. Additionally, relatively new solution – lateral reservoirs seems to be alternative preventing degradation processes. Taking into account possibility of using satellite imagery, there was observed that resolutions of Sentinel-2 satellite imagery allow to monitor vegetation processes in terms of time and space. The major limitation of using remote sensing data is high cloud density, which significantly reduces the number of observations during most of the year.
3

Heavy metal transport in a river-reservoir system: a case study from central Poland

81%
Sojka M., Siepak M., Jaskula J., Wicher-Dysarz J.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 4
The aim of this study was to analyze the heavy metals transport in a river-reservoir system. Sediment samples from 25 locations (9 from the Powa River and 16 from the Stare Miasto Reservoir) were analyzed for trace metals contents (Cr, Ni, Cu, Zn, Cd, and Pb). The relationships between heavy metal concentrations and bottom sediment physical properties were determined with the use of the multivariate statistical techniques cluster analysis (CA), principal component analysis (PCA), and canonical correspondence analysis (CCA). The results showed that concentrations of heavy metals in the sediments of the reservoir were higher than those in the bottom sediments of the river. Concentrations of heavy metals in bottom sediments in the river above the reservoir were characterized by lower spatial variability. Decisive influence on heavy metal concentrations of bottom sediments had silt, clay, and total organic matter content.
4

Analysis of heavy metals contamination in bottom sediments of lakes located in the Gniezno Lakeland

81%
Sojka M., Jaskula J., Wrozynski R.
Acta Scientiarum Polonorum. Formatio Circumiectus
|
2019
|
tom 18
|
nr 4
Aim of the study The aim of the study was to assess the degree of heavy metal pollution in bottom sediments of lakes on the basis of geochemical and ecotoxicological indicators. Material and methods The analysis was conducted for 16 lakes located in the Gniezno Lakeland in central-western Poland. The studied lakes were included in the research program obtained from the Inspector of Environmental Protection within the framework of the State Environmental Monitoring. The Contamination Factor (CF), Pollution Load Index (PLI) and Metal Pollution Index (MPI) were calculated to assess the level of sediment contamination. Assessment of the potential toxic effects of heavy metals accumulated in bottom sediments were made on the basis of TEC, MEC and PEC values. Cluster analysis (CA) was used to show similarities between lakes in terms of heavy metal concentration in bottom sediments. To identify factors affecting metal content in bottom sediments and potential sources of pollution, the PCA analysis was applied. Results and conclusions The analyses showed a large variation of heavy metals concentration in bottom sediments. The bottom sediments of lakes were polluted mostly with lead. High concentrations of lead in individual lakes may cause harm to living organisms. The lowest concentrations of heavy metals were found in the bottom sediments of Kamienieckie Lake and the highest in Ostrówieckie Lake. Cluster analysis allowed to divide the lakes into two groups with similar concentration of heavy metal in bottom sediments. The studies did not allow to clearly expose the factors responsible for determining the heavy metal content in bottom sediments of lakes.
5

Analysis of selected reservoirs functioning in the Wielkopolska region

81%
Sojka M., Jaskula J., Wicher-Dysarz J., Dysarz T.
Acta Scientiarum Polonorum. Formatio Circumiectus
|
2017
|
tom 16
|
nr 4
6
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Analysis of the use of selected reservoirs in the Wielkopolska province

81%
Waligorski B., Sojka M., Jaskula J., Korytowski M.
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
|
2018
|
tom 50
|
nr 4
7

Wyznaczenie przepływu brzegowego na wybranym odcinku rzeki Powy

71%
Wicher-Dysarz J., Dysarz T., Jaskula J., Sojka M., Grabowski D.
Acta Scientiarum Polonorum. Formatio Circumiectus
|
2016
|
tom 15
|
nr 4
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.