Analysis of heavy metal in bottom deposits of small rivers effected by agricultural reclamation on Sredneamurskaya lowland

Abstract

The relevance of the work is caused by the need to assess the ecological status of watercourses by the change of heavy metals in sediments of small rivers which can serve as an indicator of ecological state of floodplain-channel complexes and the integral indicator of water surface pollution degree because of potential for accumulation of various pollutants in the catchment area for a long period of time. The main aim of the study is the assessment of the environmental status of watercourses by the change of heavy metals in sediments of small rivers effected by reclamation in Sredneamurskaya lowland, compared with the baseline values, and during the growing season. The methods used in the study: atomic absorption spectrometry on the spectrometer "Solaar 6M" and calculation of total fertility contamination of sediments in streams. The results: The authors have found out that the content of heavy metals in sediments in the background points differ significantly from each other, and the concentration of natural pollutants is higher by several orders of magnitude than the natural and man-made ones. The bottom sediments selected from points in the background when there was a significant migration of heavy metals from flooded flood plain soils have the highest coefficients of total pollution. In the points investigated the total water content influences due to the coefficient of surface and drainage runoff the decrease of concentration of sediment pollution in comparison with the background. Agricultural drainage reclamation has a direct effect on bottom sediments; the latter can turn into a source of secondary pollution of surface waters.

Keywords

• sediments
• drainage reclamation
• heavy metals
• small watercourses
• Middle Amur lowland