[Relationships between the Biomass and Production of Bacterio- and Phytoplanktonic Communities].

Quantitative ratios of the biomasses of bacterio- and phytoplankton, interrelation of their production characteristics, and association of the functional characteristics with environmental factors were studied for Lake Khanka, the Yenisei River and the Krasnoyarsk Reservoir. The ratio between the biomasses of bacterioplankton (Bb) and phytoplankton (Bp) in these water bodies was shown to vary within the range exceeding three orders of magnitude. Bacterioplankton biomass was relatively stable and varied from sample to sample by an order of magnitude. In more than 50% of the samples (total sample number, 495), bacterioplankton biomass exceeded that of the phytoplankton. The average Bb/Bp ratios for Lake Khanka, Yenisei River, and Krasnoyarsk Reservoir were 5.1, 2, and 1.4, respectively. Increased Bb/Bp ratios were found to correlate with elevated specific (per unit biomass) phytoplankton production. This finding indicated additional supply of biogenic elements to phytoplankton due to their recycling by bacterial communities. The ratio between bacterioplankton and phytoplankton production for Lake Khanka varied from year to year (0.07 to 0.76). For the Yenisei River and the Krasnoyarsk Reservoir these ratios were on average 0.19 and 0.27, respectively. According to the literature data for other water bodies, bacterial production may reach from 10 to over 100% of the primary production. The equilibrium density of bacterioplankton (maximal density of the population) in Lake Khanka was ~1.5 times higher than in the Yenisei River and the Krasnoyarsk Reservoir due to higher content of suspended mineral matter and associated organo-mineral detritus in the lake. The interaction between dissolved organic compounds sorbed of the surface of mineral particles results in chemical alteration of biochemically stable substrate into compounds which may be assimilated by aquatic micoorganisms.

[Effect of mineral suspended matter on the productive characteristics of bacterioplankton and the degradation of labile organic materials]. / Vliianie mineral'noi vzvesi na funktsional'nye kharakteristiki bakterioplanktona i destruktsiiu labil'nogo organicheskogo veshchestva.

The effect of mineral particulate matter on the population of bacterioplankton, its aggregation, and productive characteristics was studied in model experiments with different concentrations of particulate kaolin and the same concentration of organic substance (sodium humate). It was found that the presence of mineral particulate matter stimulated the aggregation of bacterioplankton, improved bacterial production, and extended the productive period of bacterioplankton. The integral specific production of aggregated bacterioplankton was higher than that of free-swimming bacterioplankton. The energy metabolic coefficient K2 of bacterioplankton in the presence of mineral particulate matter was higher than in its absence.

[Functional characteristics of bacterioplankton with reference to its aggregation in water bodies of different types]. / Funktsional'nye kharakteristiki bakterioplanktona v sviazi s ego agregirovannost'iu v vodoemakh raznogo tipa.

The functional characteristics of bacterioplankton have been studied with reference to its aggregation in water bodies of different types. Several methods were used for calculation of the total numbers of bacteria and proportion of aggregated cells. Analysis of the experimental data has shown a relationship between the functional characteristics of bacterioplankton, such as bacterial production, destruction of organic matter, and energy coefficient, and the proportion of aggregated bacteria. It has been shown that as this proportion increases, the production per cell and energy coefficients also increase.

[Effect or preliminary filtration on the functional characteristics of bacterioplankton from Lake Khanka]. / Vliianie predvaritel'noi fil'tratsii na funktsional'nye kharakteristiki bakterioplankton ozera Khanka.

The dependence of the functional characteristics of bacterioplankton from the loess of Lake Khanka on the pore size of filtering materials was investigated. Soluble organic matter (SOM), bacteria, and bacterial consumers adsorbed on particles suspended in the lake water were found to filter differently depending on the pore size of the filtering material. Filters with pore size 4.5 microns (filters II) retained up to 20% of SOM and 20-30% of bacterial cells. Filters III with pore size 2.87 microns retained almost 50% SOM and about 40% of bacteria. The double layer of gauze no. 72 (referred to as filter I) with pores size 40 microns was unable to completely retain bacterial consumers. In the case of filtrates I and II, the generation time of bacterioplankton decreased with its increasing average daily concentration. In the case of filtrate III, the generation time of bacterioplankton was minimum and did not depend on its concentration. Oxygen consumption rates per one bacterial cell and per unit biomass in filtrates increased with decreasing pore size of the filters through which they had passed. The bacterial biomass and oxygen consumption rate increased exponentially in filtrates III and logarithmically in filtrates I.

[Characteristics of bacterioplankton in the Loess-containing Lake Khanka]. / Issledovanie kharakteristik bakterioplankton ozera Khanka v sviazi s lessovost'iu vodoema.

Some characteristics of bacterioplankton--generation time, daily (P) and specific (P/B) bacterioplankton production, and bacterial metabolic coefficient K2--in the loess-containing Lake Khanka were determined using five modifications of the bacterial-count procedure with the fluorescent dyes fluorescamin and erythrosin. Experiments showed that the organomineral complex (OMC) in this lake is broken down by chemoorganoheterotrophic bacteria. The increase in the loess content of the lake water intensified bacterial growth and the cycles of potassium, silicon, and other biogenic elements. The addition of starch to a loess suspension activated the breakdown of OMC due to the adsorption of starch on the OMC/water interface and stimulation of the metabolism of attached bacteria.