Microbe abundance and biomass in the euphotic zone of the Aegean Sea at Station MARCH-1997-GN36199704601MSB07 in spring 1997
2019-11-21T20:41:10Z (GMT) by
10-30 ml subsamples were concentrated on 25 mm black polycarbonate filters (0.6 µm for NF, 0.2 µm for B), stained with DAPI for 10 min and filtered. NF were counted using UV and blue excitation and enumerated. Heterotrophic B were counted using UV excitation. NF were classified in size categories and biovolume was calculated. NF abundance data were converted into C biomass using 220 fgC µm**-3. Bact abund data were converted into C biomass using 20 fgC cell**-1. BP C was estimated by the 3H-leucine approach according to Kirchman et al. (1986) and Kirchman D.L., 1993. Leucine incorporation as a measure of biomass production by heterotrophic bacteria. In: Kemp P.F. et al. (eds), 1993. Handbook of methods in aquatic microbial ecology. Lewis Publishers, Ann Arbor, 509-512). At each depth duplicate samples and a control one were incubated with 1 nM L-[4,5 3H]-leucine (specific activity 128 Ci/mmol) and 18 nM non-radioactive leucine. Samples were incubated in the dark at in situ temperature.