Denaturing gradient gel electrophoresis (DGGE) band patterns with specific primers for Bacteria 16S rRNA gene fragment in sediment (a) and water (b) samples. Band patterns resulted from 30-70% (a) and 40-70% (b) denaturing gradients. Sediment patterns are D for dry and R for rainy seasons, and their respective depths: 1) surface (0–5 cm), 2) 5–15 cm, 3) 15–25 cm and 4) 25–35 cm. The water DGGE pattern is derived from rainy samples. Bands with numbers were excised from the gels and sequenced. Sequences were identified by the prefix describing the community sampled (Rw, Rs, Dw and Ds), technique used (db for DGGE and bacteria) and ID number.