Fig. 1.
Potential denitrification activity in sediments of hypersaline soda lakes in Kulunda Steppe (Altai, Russia). a Potential nitrate (2 mM) reduction to N2O in natural sediment slurries with different electron donors (4 mM). b Reduction of different nitrogen oxides in the presence of 4 mM acetate in natural sediments. c, d Influence of pH (at 0.6 M total Na+) and soda (at pH 10), respectively, on nitrate reduction with 4 mM acetate in sediments freed from the pore waters and suspended in salt buffers. The solid lines depict N2O formation in the presence of acetylene and the dashed lines depict nitrite formation; open circles lake Picturesque; closed circles lake Tanatar-5; open triangles lake Bitter-1