Well-drilling fluid and a number of the known components (barite, clay, Aldacide, Surflo, and Dowicide, were tested for effects on the biomass and community structure of the microbiota that colonize marine sands exposed for eight weeks to running ambient seawater. Shading the microbiota from light depressed the microflora without a significant effect on the biomass, while well-drilling fluids l...

Loblolly and slash pine seed were inoculated at sowing with 1 of 12 different strains of plant growth-promoting rhizobacteria (PGPR) in the greenhouse. Time to germination and seedling densities were determined at 21 days, and seedling biomass was measured at 12 wk after sowing. All bacterial strains significantly increased the speed of seedling emergence over nontreated pine seed. By 12 wk, ho...

Biomass, production and heterotrophic activity of bacterioplankton were determined for two weeks in the Great Astrolabe Reef lagoon, Fiji. Bacterial and Bacterial activities were distributed homogeneously throughout the water column (20 to 40m deep) and varied little from site to site inside the lagoon. Bacterioplankton biomass and production also varied little over a diel period with coefficie...

Soil physicochemical properties, soil microbial biomass and bacterial community structures in a rice-wheat cropping system subjected to different fertilizer regimes were investigated in two seasons (June and October). All fertilizer regimes increased the soil microbial biomass carbon and nitrogen. Both fertilizer regime and time had a significant effect on soil physicochemical properties and ba...

conclusions we found ccd and rsm very effective in optimizing hib culture conditions, and hib biomass production was greatly influenced by ph and incubation temperature. therefore, optimization of the growth factors to maximize hib production can lead to 1) an increase in bacterial biomass and prp productions, 2) lower vaccine prices, 3) vaccination of more susceptible populations, and 4) lower...

In order to better estimate bacterial biomass in marine environments, we developed a novel technique for direct measurement of carbon and nitrogen contents of natural bacterial assemblages. Bacterial cells were separated from phytoplankton and detritus with glass fiber and membrane filters (pore size, 0.8 &mgr;m) and then concentrated by tangential flow filtration. The concentrate was used for ...

We measured bacterial abundance, cell size distribution, and related microbiological and geochemical parameters in 20 stratified lakes from three regions in the U.S. Both largest cell size and greatest bacterial abundance occurred in anoxic waters. Bacterial size distributions from the hypolimnia of lakes that were oxic were identical to those in surface waters. Bacteria from anoxic hypolimnia ...

An assessment of roles of rhizospheric microbial diversity in plant growth is helpful in understanding plant-microbe interactions. Using random combinations of rhizospheric bacterial species at different richness levels, we analysed the contribution of species richness, compositions, interactions and identity on soil microbial respiration and plant biomass. We showed that bacterial inoculation ...

Bacterial growth and its interaction with water flow was investigated in a two-dimensional flow field in a saturated porous medium. A flow cell (56 x 44 x 1 cm) was filled with glass beads and operated under a continuous flow of a mineral medium containing nitrate as electron acceptor. A glucose solution was injected through an injection port, simulating a point source contamination. Visible li...

The effects of mine drainage on 2 bacterial processes were examined in Rocky Mountain streams affected by mine drainage. Thymidine incorporation into bacterial DNA was measured as an index of bacterial production, and nitrification was examined because it is sensitive to a variety of stressors. These processes, as well as pH, concentration of dissolved Zn, and deposition rate of metal oxides, a...