DBPapers
DOI: 10.5593/sgem2017/23/S11.083

SPATIOTEMPORAL CHANGES OF THE PLOUCNICE RIVER FOR THE EXPLANATION OF POLLUTION DISTRIBUTION IN THE FLOODPLAIN

J. Elznicova, D. Hrubesova
Thursday 14 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-03-4 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 23, 665-672 pp, DOI: 10.5593/sgem2017/23/S11.083

ABSTRACT

The Ploučnice River (the Czech Republic) has been impacted by the uranium mining in the Stráž pod Ralskem area mainly from 1971 to 1987. The extreme flood in 1981 contaminated the Ploučnice River system by uranium, radium and also by heavy metals. The pollutants are now deposited all over the floodplain downstream from the mining area. Other extreme flood in 2010 caused the remobilization of deposited pollution. This paper is focused on the spatiotemporal changes of the Ploučnice River between Stráž pod Ralskem town and Česká Lípa town during the last two centuries that is relevant for understanding the past and prediction of the future secondary pollution. On the basis of the comparison of several datasets (archival documents of the 19th century, archive aerial photos from 1938 to 2015, the aerial mapping of gamma activity in 2005, and the digital terrain model from the laser scanning dataset from 2010) we report on the Ploučnice River development. Aerial photos were orthorectified in Agisoft PhotoScan software. Dataset of the river development was prepared and then analyzed in ArcGIS Desktop 10.4 software. The parts of natural evolution of meanders, as well as the parts of anthropogenic straightening on the Ploučnice River were identified. The results of the analysis showed a relationship between transfer of polluted sediment and lateral channel shifts. It was identified that the heterogeneity of the pollution and increased concentration of pollution occurred mainly by the past meander abandonments and channel shifts.

Keywords: spatiotemporal change, the Ploučnice River, pollution, aerial photo, digital terrain model