Two decades of trends in ground water chemical composition in The Great Vasyugan Mire, Western Siberia, Russia

Boreal wetlands cover approximately 30 % of the West Siberian Plain (WSP). The Great Vasyugan Mire, Northern Hemisphere’s largest contiguous wetlands, occupies low-lying plains in the Ob and Irtysh’s interfluve. Most research has investigated the peat generating processes and reserves in the WSP wetlands. Little information exists about temporal changes in the chemical composition of the wetland waters within the Ob–Irtysh interfluve. Although the region’s climate is continental with extended cold winters and short hot summers, Western Siberia is experiencing rapid climatic changes. The consequences of these changes include permafrost loss, snow cover reduction, and river flow changes. In this study whether and how increasing surface air temperatures contributed to changes in the chemical composition of the atmospheric precipitation and water in the mire were investigated. Time-series analysis and multivariate statistics on the hydrochemical data collected between 1994 and 2013 at several sampling sites were used to evaluate the statistical significance of the possible correlations between the increasing surface air temperatures and various chemical constituents in the precipitation and the wetland water.