Spatial Distribution and Interannual Dynamics of Bacterioplankton in the Taishir and Durgun Reservoirs (Western Mongolia
- PDF / 1,026,050 Bytes
- 12 Pages / 612 x 792 pts (letter) Page_size
- 10 Downloads / 204 Views
TIC MICROBIOLOGY
Spatial Distribution and Interannual Dynamics of Bacterioplankton in the Taishir and Durgun Reservoirs (Western Mongolia) D. B. Kosolapova, b, * a
Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Nekouzskii raion, Yaroslavl oblast, Russia b Cherepovets State University, Cherepovets, Russia *e-mail: [email protected] Received January 13, 2018; revised February 6, 2019; accepted July 22, 2019
Abstract—The spatial distribution and interannual dynamics of the abundance and biomass of heterotrophic bacterioplankton have been evaluated in two recently formed large freshwater reservoirs (the Taishir and Durgun reservoirs, the Great Lakes Depression, Western Mongolia). The total abundance of bacteria range from 2.5 × 106 to 14.5 × 106 cells/mL; biomass is from 45 to 386 mg C/m3. These parameters reach the level of eutrophic waters in both reservoirs, but they are on average 1.4 times higher in the Durgun reservoir. The bacterioplankton of the reservoirs is probably in the formation stage. Free-living cells are the basis of the number and biomass of bacterioplankton. They average 91.0% of the total biomass. The larger aggregated and filamentous bacteria contribute significantly less to the total biomass of the community—an average of 6.7 and 2.3%, respectively—and reach the highest abundance and biomass in the littoral zone of the reservoirs. Keywords: bacterioplankton, spatial distribution, interannual dynamics, reservoirs, Mongolia DOI: 10.1134/S1995082920030098
INTRODUCTION In modern Mongolia, there is acceleration in the growth rate of industrial production and an increase in housing construction. This requires high energy costs and the construction of a hydroelectric station, which leads to the restructuring of rivers and the formation of reservoirs. The study of the formation of biological communities of reservoirs is necessary for understanding the general laws of the structural and functional organization of these artificial ecosystems at different stages of their existence. This is especially important when studying aquatic ecosystems in arid regions that are related to the Great Lakes Basin in Western Mongolia (Murzaev, 2006). Cattle breeding is traditional for Mongolia, and there is currently an increase in the number of farm animals; as a result, organic matter and compounds of nutrients are increasing in water bodies and streams. Mineral resources extraction is also increasing. In addition, under the conditions of modern climatic changes, an increase in precipitation is observed, surface runoff and evaporation increase, and the level and water exchange of lakes and river discharge decrease. All these factors contribute to the eutrophication of aquatic ecosystems in Mongolia (Gomboluudev et al., 2010). Heterotrophic bacteria are an important component of freshwater and marine plankton, making a sig-
nificant contribution to the formation of its biomass and productivity; actively participating in the mineralization of organic substances, the circulation of element
Data Loading...
