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1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Prokopkin I.G., Mooij W.M., Janse J.H., Degermendzhy A.G.
Заглавие : A general one-dimensional vertical ecosystem model of Lake Shira (Russia, Khakasia): Description, parametrization and analysis
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 585-618. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9326-8
Ключевые слова (''Своб.индексиров.''): meromictic brackish lake--one-dimensional vertical ecological model--sensitivity analysis--alga--biomass--brackish water--diffusion--ecosystem modeling--meromictic lake--microbial community--model test--nutrient--one-dimensional modeling--parameterization--phytoplankton--seasonality--sensitivity analysis--solar radiation--vertical profile--water chemistry--water temperature--zooplankton--khakassia--lake shira--russian federation--algae
Аннотация: A one-dimensional ecological model of the meromictic brackish Lake Shira (Russia, Khakasia) was developed. The model incorporates state-of-the-art knowledge about the functioning of the lake ecosystem using the most recent field observations and ideas from PCLake, a general ecosystem model of shallow freshwater lakes. The model of Lake Shira presented here takes into account the vertical dynamics of biomasses of the main species of algae, zooplankton and microbial community, as well as the dynamics of oxygen, detritus, nutrients and hydrogen sulphide from spring to autumn. Solar radiation, temperature and diffusion are modelled using real meteorological data. The parameters of the model were calibrated to the field data, after applying different methods of sensitivity analysis to the model. The resulting patterns of phytoplankton and nutrients dynamics show a good qualitative and quantitative agreement with the field observations during the whole summer season. Results are less satisfactory with respect to the vertical distribution of zooplankton biomass. We hypothesize that this is due to the fact that the current model does not take the sex and age structure of zooplankton into account. The dynamics of oxygen, hydrogen sulphide and the modelled positions of the chemocline and thermocline are again in good agreement with field data. This resemblance confirms the validity of the approach we took in the model regarding the main physical, chemical and ecological processes. This general model opens the way for checking various hypotheses on the functioning of the Lake Shira ecosystem in future investigations and for analysing options for management of this economically important lake. В© 2010 Springer Science+Business Media B.V.
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2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zadereev E.S., Tolomeev A.P., Drobotov A.V.
Заглавие : Asynchronous vertical migrations of zooplankton in stratified lakes
Место публикации : Contemporary Problems of Ecology. - 2012. - Vol. 5, Is. 4. - С. 443-449. - ISSN 19954255 (ISSN) , DOI 10.1134/S1995425512040166
Ключевые слова (''Своб.индексиров.''): individual migrations--stratified lakes--zooplankton--crustacean--epilimnion--hypolimnion--lake ecosystem--thermocline--vertical migration--zooplankton--siberia--arctodiaptomus salinus--calanoida--copepoda
Аннотация: Asynchronous vertical migrations of calanoid copepods Arctodiaptomus salinus were studied in two stratified lakes in the south of Siberia using the method of two-section enclosures. It was found that the presence of a pronounced thermocline and a depth maximum of phytoplankton (Lake Shira) contributes to the appearance of intensive individual migrations of copepods between areas of the epi- and hypolimnion. В© 2012 Pleiades Publishing, Ltd.
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3.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zadereev E.S., Tolomeev A.P., Drobotov A.V., Kolmakova A.A.
Заглавие : Impact of weather variability on spatial and seasonal dynamics of dissolved and suspended nutrients in water column of meromictic Lake Shira
Колич.характеристики :13 с
Коллективы : Siberian Branch of the Russian Academy of Sciences (SB RAS) [56]; Russian Foundation for Basic Research [13-05-00853]
Место публикации : Contemp. Probl. Ecol.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2014. - Vol. 7, Is. 4. - С. 384-396. - ISSN 1995-4255, DOI 10.1134/S199542551404012X. - ISSN 1995-4263
Примечания : Cited References: 25. - This work was performed with the partial support of the Siberian Branch of the Russian Academy of Sciences (SB RAS) Integration Project no. 56 and grant 13-05-00853 of the Russian Foundation for Basic Research. The work was performed using resources of the field station of the SB RAS Institute of Biophysics (IBP) at Shira Lake. We thank our colleagues from the SB RAS IBP Laboratory of Biophysics of Ecosystems for their friendly participation in joint field works at Shira Lake; Academician A. G. Degermendzhi for his support of research at the saline lakes of Khakassia; the research workers of the SB RAS IBP Analytical Laboratory for the analyses of water and seston samples; and we especially thank Dr. Denis Rogozin for arrangements and assistance in winter field trips to the lakes, as well as to an anonymous reviewer for his valuable comments.
Предметные рубрики: CLIMATE-CHANGE
STRATIFICATION
PHOSPHORUS
RUSSIA
PHYTOPLANKTON
SESTON
Ключевые слова (''Своб.индексиров.''): meromictic lake--weather--thermal stratification--seston--nutrients--stoichiometric ratios
Аннотация: Depths of thermocline and the redox zone, concentrations of dissolved and suspended carbon, and nitrogen and phosphorus in seston were measured in the pelagial of the saline meromictic Lake Shira (southern Siberia) in different years (2007-2011); the relationship of the values for those parameters with air-temperature variations was assessed. Positive correlations between both air temperatures in the previous year and the depth of the redox zone in winter and air temperature in April and the thermocline depth in summer were revealed. In the mixolimnion, the ratio of total nitrogen to total phosphorus almost always exceeded the Redfield ratio (16: 1); seston deficiency both in nitrogen and phosphorus was monitored in different seasons and at various depths. The amount of seston in the mixolimnion in summer almost doubled the amount of seston in winter and was directly related with the depth of the thermocline. In the monimolimnion, seston was rich in nitrogen and phosphorus. The amount of seston in the monimolimnion varied in different years and depended both on the air temperature in the previous year and the size of the zone.
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4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pimenov N.V., Rusanov I.I., Karnachuk O.V., Rogozin D.Yu., Bryantseva I.A., Lunina O.N., Yusupov S.K., Parnachev V.P., Ivanov M.V.
Заглавие : Microbial processes of the carbon and sulfur cycles in Lake Shira (Khakasia)
Место публикации : Mikrobiologiya. - 2003. - Vol. 72, Is. 2. - С. 259-267. - ISSN 00263656 (ISSN)
Ключевые слова (''Своб.индексиров.''): anoxygenic photosynthesis--lake shira--production and oxidation of methane--purple sulfur bacteria--sulfate reduction--bacteria (microorganisms)--chromatiaceae--lamprocystis--proteobacteria--thiocapsa--carbon--fresh water--methane--sulfate--sulfur--article--chromatiaceae--comparative study--metabolism--microbiology--oxidation reduction reaction--photosynthesis--russian federation--carbon--chromatiaceae--fresh water--methane--oxidation-reduction--photosynthesis--russia--sulfates--sulfur
Аннотация: Microbiological and biogeochemical studies of the meromictic saline Lake Shira (Khakasia) were conducted. In the upper part of the hydrogen-sulfide zone, at a depth of 13.5-14 m, there was a pale pink layer of water due to the development of purple bacteria (6 ? 10 5 cells/ml), which were assigned by their morphological and spectral characteristics to Lamprocystis purpureus (formerly Amoebobacter purpurea). In August, the production of organic matter (OM) in Lake Shira was estimated to be 943 mg C/(m 2 day). The contribution of anoxygenic photosynthesis was insignificant (about 7% of the total OM production). The share of bacterial chemosynthesis was still less (no more than 2%). In the anaerobic zone, the community of sulfate-reducing bacteria played a decisive role in the terminal decomposition of OM. The maximal rates of sulfate reduction were observed in the near-bottom water (114 ?g S/(1 day)) and in the surface layer of bottom sediments (901 ?g S/(dm 3 day)). The daily expenditure of C org for sulfate reduction was 73% of C org formed daily in the processes of oxygenic and anoxygenic photosynthesis and bacterial chemosynthesis. The profile of methane distribution in the water column and bottom sediments was typical of meromictic reservoirs. The methane content in the water column increased beginning with the thermocline (7-8 m), and reached maximum values in the near-bottom water (17 ?l/l). In bottom sediments, the greatest methane concentrations (57 ?l/l) were observed in the surface layer (0-3 cm). The integral rate of methane formation in the water column and bottom sediments was almost an order of magnitude higher than the rate of its oxidation by aerobic and anaerobic methanotrophic microorganisms.
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5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pimenov N.V., Rusanov I.I., Karnachuk O.V., Rogozin D.Yu., Bryantseva I.A., Lunina O.N., Yusupov S.K., Parnachev V.P., Ivanov M.V.
Заглавие : Microbial processes of the carbon and sulfur cycles in Lake Shira (Khakasia)
Место публикации : Microbiology. - 2003. - Vol. 72, Is. 2. - С. 221-229. - ISSN 00262617 (ISSN) , DOI 10.1023/A:1023228316838
Ключевые слова (''Своб.индексиров.''): anoxygenic photosynthesis--lake shira--production and oxidation of methane--purple sulfur bacteria--sulfate reduction--bacteria (microorganisms)--chromatiaceae--lamprocystis purpurea--proteobacteria--thiocapsa
Аннотация: Microbiological and biogeochemical studies of the meromictic saline Lake Shira (Khakasia) were conducted. In the upper part of the hydrogen-sulfide zone, at a depth of 13.5-14 m, there was a pale pink layer of water due to the development of purple bacteria (6 ? 105 cells/ml), which were assigned by their morphological and spectral characteristics to Lamprocystis purpurea (formerly Amoebobacter purpureus). In August, the production of organic matter (OM) in Lake Shira was estimated to be 943 mg C/(m2 day). The contribution of anoxygenic photosynthesis was insignificant (about 7% of the total OM production). The share of bacterial chemosynthesis was still less (no more than 2%). In the anaerobic zone, the community of sulfate-reducing bacteria played a decisive role in the terminal decomposition of OM. The maximal rates of sulfate reduction were observed in the near-bottom water (114 ?g S/(1 day)) and in the surface layer of bottom sediments (901 ?g S/(dm3 day)). The daily expenditure of Corg for sulfate reduction was 73% of Corg formed daily in the processes of oxygenic and anoxygenic photosynthesis and bacterial chemosynthesis. The profile of methane distribution in the water column and bottom sediments was typical of meromictic reservoirs. The methane content in the water column increased beginning with the thermocline (7-8 m) and reached maximum values in the near-bottom water (17 ?l/l). In bottom sediments, the greatest methane concentrations (57 ?l/l) were observed in the surface layer (0-3 cm). The integral rate of methane formation in the water column and bottom sediments was almost an order of magnitude higher than the rate of its oxidation by aerobic and anaerobic methanotrophic microorganisms.
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6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pimenov N.V., Rusanov I.I., Karnachuk O.V., Rogozin D.Y., Bryantseva I.A., Lunina O.N., Yusupov S.K., Parnachev V.P., Ivanov M.V.
Заглавие : Microbial processes of the carbon and sulfur cycles in Lake Shira (Khakasia)
Колич.характеристики :9 с
Место публикации : Microbiology: MAIK NAUKA/INTERPERIODICA, 2003. - Vol. 72, Is. 2. - P221-229. - ISSN 0026-2617, DOI 10.1023/A:1023228316838
Примечания : Cited References: 17
Предметные рубрики: BACTERIA
NOV
Ключевые слова (''Своб.индексиров.''): lake shira--anoxygenic photosynthesis--purple sulfur bacteria--sulfate reduction--production and oxidation of methane
Аннотация: Microbiological and biogeochemical studies of the meromictic saline Lake Shira (Khakasia) were conducted. In the upper part of the hydrogen-sulfide zone, at a depth of 13.5-14 m, there was a pale pink layer of water due to the development of purple bacteria (6 x 10(5) cells/ml), which were assigned by their morphological and spectral characteristics to Lamprocystis purpurea (formerly Amoebobacter purpureus). In August, the production of organic matter (OM) in Lake Shira was estimated to be 943 mg C/(m(2) day). The contribution of anoxygenic photosynthesis was insignificant (about 7% of the total OM production). The share of bacterial chemosynthesis was still less (no more than 2%). In the anaerobic zone, the community of sulfate-reducing bacteria played a decisive role in the terminal decomposition of OM. The maximal rates of sulfate reduction were observed in the near-bottom water (114 mug S/(1 day)) and in the surface layer of bottom sediments (901 mug S/(dm(3) day)). The daily expenditure of C-org for sulfate reduction was 73% of C-org formed daily in the processes of oxygenic and anoxygenic photosynthesis and bacterial chemosynthesis. The profile of methane distribution in the water column and bottom sediments was typical of meromictic reservoirs. The methane content in the water column increased beginning with the thermocline (7-8 m) and reached maximum values in the near-bottom water (17 mul/l). In bottom sediments, the greatest methane concentrations (57 mul/l) were observed in the surface layer (0-3 cm). The integral rate of methane formation in the water column and bottom sediments was almost an order of magnitude higher than the rate of its oxidation by aerobic and anaerobic methanotrophic microorganisms.
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7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Rogozin D.Y., Genova S.N., Gulati R.D., Degermendzhy A.G.
Заглавие : Some generalizations based on stratification and vertical mixing in meromictic Lake Shira, Russia, in the period 2002-2009
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 485-496. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9328-6
Ключевые слова (''Своб.индексиров.''): 1-d model--meromixis--mixolimnion--oxic-anoxic interface--thermocline--weather conditions--brackish water--meromictic lake--numerical model--one-dimensional modeling--overturn--physicochemical property--salinity--seasonality--stratification--temperate environment--vertical mixing--water temperature--weather--khakassia--lake shira--russian federation
Аннотация: In a brackish, temperate, 24-m-deep Lake Shira, the profiles of salinity, temperature, oxygen and sulfide concentrations were measured on a seasonal basis from 2002 to 2009. The lake was shown to be meromictic with autumnal overturn restricted to mixolimnion. The depth of mixolimnion and position of oxic-anoxic interface varied annually. The spring mixing processes contribute to the formation of mixolimnion in autumn. The exceptionally windy spring of 2007 caused the deepening of mixolimnion in the winter of 2008. The winter position of oxic-anoxic interface was affected by the position of lower boundary of mixolimnion in all winters. The salinity in the winter mixolimnion increased compared with the autumn because of freezing out of salts from the upper water layers meters during ice formation and their dissolution in water below. The profiles of salinity and temperature were simulated by the mathematical 1-D model of temperature and salinity conditions taking into account ice formation. The simulated profiles generally coincided with the measured ones. The coincidence implies that simplified one-dimensional model can be applied to roughly describe salinity and density profiles and mixing behavior of Lake Shira. В© 2010 The Author(s).
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8.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Zadereev E.S., Tolomeyev A.P., Drobotov A.V., Emeliyanova A.Y., Gubanov M.V.
Заглавие : The vertical distribution and abundance of Gammarus lacustris in the pelagic zone of the meromictic lakes Shira and Shunet (Khakassia, Russia)
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 531-539. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9329-5
Ключевые слова (''Своб.индексиров.''): amphipod--gammarus lacustris--meromictic lake--thermocline--vertical distribution--abundance--amphipod--dissolved oxygen--intertidal environment--meromictic lake--pelagic environment--seston--stratification--thermocline--vertical distribution--videography--water temperature--khakassia--lake shira--lake shunet--russian federation--amphipoda--animalia--gammarus--gammarus lacustris
Аннотация: The vertical distribution and abundance of Gammarus lacustris in the pelagic zone of two fishless meromictic lakes, L. Shira and L. Shunet, in Southern Siberia (Russia), was studied with the underwater video recording system and using vertical hauls. In both lakes, during summer stratification, Gammarus was distributed non-homogenously, with a stable peak in the metalimnion. The average depth of Gammarus population in the pelagic zone was significantly correlated with the depth of the thermocline. Gammarus abundances obtained using vertical plankton hauls with net were quite comparable with those obtained from video records. The peak abundance of Gammarus in the pelagic zone of the lakes observed with underwater video amounted up to 400 individuals m-2, while the peak animal densities in the metalimnion reached 50 ind. m-3. The data are compared with previously published abundances of Gammarus in the littoral of Lake Shira. Both littoral and pelagic can be equally important habitats for amphipods in meromictic lakes. The absence of fish in the pelagic zone, high oxygen concentration, low water temperature, increased seston concentration, elevated water density in the metalimnion and the anoxic hypolimnion can be the most probable combination of factors that are responsible for the peak of Gammarus in the metalimnion of these lakes. В© 2010 Springer Science+Business Media B.V.
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9.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Degermendzhy A.G., Zadereev E.S., Rogozin D.Y., Prokopkin I.G., Barkhatov Y.V., Tolomeev A.P., Khromechek E.B., Janse J.H., Mooij W.M., Gulati R.D.
Заглавие : Vertical stratification of physical, chemical and biological components in two saline lakes Shira and Shunet (South Siberia, Russia)
Место публикации : Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - С. 619-632. - ISSN 13862588 (ISSN) , DOI 10.1007/s10452-010-9336-6
Ключевые слова (''Своб.индексиров.''): ciliates--cryptomonas--fishless lakes--gammarus--mathematical modelling--meromictic lakes--phytoplankton--stratification--sulphur bacteria--amphipod--bacterium--biomass--ciliate--ecosystem modeling--flagellate--meromictic lake--microbial community--numerical model--physicochemical property--phytoplankton--population density--saline lake--salinity--stratification--thermocline--trophic interaction--vertical profile--zooplankton--khakassia--lake shira--lake shunet--russian federation--siberia--amphipoda--bacteria (microorganisms)--ciliophora--copepoda--cryptomonas--cryptomonas sp.--gammaridae--gammarus--gammarus lacustris--phytomastigophorea--protista--rotifera
Аннотация: A feature of meromictic lakes is that several physicochemical and biological gradients affect the vertical distribution of different organisms. The vertical stratification of physical, chemical and biological components in saline, fishless meromictic lakes Shira and Shunet (Siberia, Russia) is quite different mainly because both mean depth and maximum depth of lakes differ as well as their salinity levels differ. The chemocline of the Lake Shira, as in many meromictic lakes, is inhabited by bacterial community consisting of purple sulphur and heterotrophic bacteria. As the depth of the chemocline is variable, the bacterial community does not attain high densities. The mixolimnion in Lake Shira, which is thermally stratified in summer, also creates different habitat for various species. The distribution of phytoplankton is non-uniform with its biomass peak in the metalimnion. The distribution of zooplankton is also heterogeneous with rotifers and juvenile copepods inhabiting the warmer epilimnion and older copepods found in the cold but oxic hypolimnion. The amphipod Gammarus lacustris which can be assigned to the higher trophic link in the fishless lake's ecosystem, such as Lake Shira, is also distributed non-uniformly, with its peak density generally observed in the thermocline region. The chemocline in Lake Shunet is located at the depth of 5 m, and unlike in Lake Shira, due to a sharp salinity gradient between the mixolimnion and monimolimnion, this depth is very stable. The mixolimnion in Lake Shunet is relatively shallow and the chemocline is inhabited by (1) an extremely dense bacterial community; (2) a population of Cryptomonas sp.; and (3) ciliate community comprising several species. As the mixolimnion of Lake Shunet is not thermally stratified for long period, the phytoplankton and zooplankton populations are not vertically stratified. The gammarids, however, tend to concentrate in a narrow layer located 1-2 m above the chemocline. We believe that in addition to vertical inhomogeneities of both physicochemical parameters, biological and physical factors also play a role in maintaining these inhomogeneities. We conclude that the stratified distributions of the major food web components will have several implications for ecosystem structure and dynamics. Trophic interactions as well as mass and energy flows can be significantly impacted by such heterogeneous distributions. Species spatially separated even by relatively short distances, say a few centimetres will not directly compete. Importantly, we demonstrate that not only bacteria, phytoflagellates and ciliate tend to concentrate in thin layers but also larger-sized species such Gammarus (amphipods) can also under certain environmental conditions have stratified distribution with maxima in relatively thin layer. As the vertical structure of the lake ecosystem is rather complex in such stratified lakes as ours, the strategy of research, including sampling techniques, should consider potentially variable and non-homogeneous distributions. В© 2010 The Author(s).
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