FIG. 2.

(A) Depth distributions of acetate, formate, and sulfate concentration in the Lake Chaka sediments as determined in the “artificial pore water” created by leaching the lake sediments with distilled water. (B) Distribution of total nitrogen and organic carbon in the lake sediments. (C) Microbial abundance distribution in the lake sediments as determined by AODC and PLFA analysis. Single samples were used, and so sample-to-sample variability assessment was not possible. Single samples were measured more than once, and analytical errors were smaller than the symbol sizes.