title: 0-5 cm depth sample  aerobically incubated for 8 days with 10 mM nitrate R1
design: The 0-5 cm depth of sediment sample mixed with the estuary water (1:10;1 L) were incubated with 10 mM nitrate in 1.2-L glass bottles sealed with a rubber stopper. The headspace (ca. 200 ml) consisted of gas (N2:CO2 = 4:1). This treatment was anaerobically incubated at 25˘XC with stirring at 160 rpm for eight days. Samples (10 ml) were withdrawn at 8 days and were stored at -80˘XC