Scholarly record

CONCENTRATION OF ARSENIC IN THE SOILS OF THE DANUBE FLOODPLAIN BETWEEN THE TIMOK RIVER AND THE VIT RIVER

Velimira Stoyanova

Abstract

The aim of the current research is to present an actual and overall picture of the arsenic (As) contamination of the soils in the Bulgarian part of the Danube floodplain between the Timok River and the Vit River including the following lowlands: Bregovo-Novoselska, Vidinska, Archaro-Orsoiska, Dolnotsibarska, Kozloduyska, Ostrovska and Chernopolska. One sampling campaign was carried in October 2017. The concentrations of As (mg/kg) were measured in <0.063 mm size fractions of 102 soil samples (56 samples from 0-20 cm; 43 samples from 20-40 cm; 3 samples from 40-60 cm) using X-ray fluorescence analysis (XRF). The content of arsenic in the topsoil (0-20 cm) of the Danube floodplain ranged between 7 ? 61 mg/kg, while in the subsoil (20-40 cm) it varied from 8 to 95 mg/kg. Bregovo-Novoselska lowland turned out to be the most arsenic polluted floodplain section in the region followed by the Vidinska lowland. while the Kozloduyska. Archaro-Orsoyska. Dolnotsibarska. Ostrovska and Chernopolska lowlands were found to be less contaminated. In all samples, arsenic exceeded its average concentration in floodplain sediment (6 mg/kg) according to the Geochemical Atlas of Europe. Nearly 12% of the samples were found to be over the maximum admitted concentration (25 mg/kg), and one sample was over the intervention value (90 mg/kg). The main point sources of As pollution were suggested to be located in the Timok and Ogosta drainage sub-basins.

Publication details

Back to publication list