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1.


   
    Carbon cycle modeling and principle of the worst scenario / S. I. Bartsev, A. G. Degermendzhi, P. V. Belolipetsky // Developments in Environmental Modelling. - 2012. - Vol. 25. - P447-458, DOI 10.1016/B978-0-444-59396-2.00026-2

Scopus
Держатели документа:
Institute of Biophysics SB RAS, Krasnoyarsk, 660036, Russian Federation
INstitute of Computational Modeling SB RAS, Krasnoyarsk, 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Bartsev, S.I.; Degermendzhi, A.G.; Belolipetsky, P.V.

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2.


   
    Challenges and opportunities for integrating lake ecosystem modelling approaches / W. M. Mooij [et al.] // Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - P633-667, DOI 10.1007/s10452-010-9339-3 . - ISSN 1386-2588
Кл.слова (ненормированные):
Adaptive processes -- Analysis -- Aquatic -- Bifurcation -- Biodiversity -- Climate warming -- Community -- Eutrophication -- Fisheries -- Food web dynamics -- Freshwater -- Global change -- Hydrology -- Lake -- Management -- Marine -- Mitigation -- Model integration -- Model limitations -- Non-linear dynamics -- Nutrients -- Plankton -- Population -- Prediction -- Spatial -- Understanding -- adaptive management -- algorithm -- aquatic community -- biodiversity -- ecosystem modeling -- eutrophication -- fishery production -- food web -- fuzzy mathematics -- global warming -- hydrology -- lake ecosystem -- mitigation -- model test -- numerical model -- nutrient availability -- plankton -- prediction -- saline lake -- spatial analysis
Аннотация: A large number and wide variety of lake ecosystem models have been developed and published during the past four decades. We identify two challenges for making further progress in this field. One such challenge is to avoid developing more models largely following the concept of others ('reinventing the wheel'). The other challenge is to avoid focusing on only one type of model, while ignoring new and diverse approaches that have become available ('having tunnel vision'). In this paper, we aim at improving the awareness of existing models and knowledge of concurrent approaches in lake ecosystem modelling, without covering all possible model tools and avenues. First, we present a broad variety of modelling approaches. To illustrate these approaches, we give brief descriptions of rather arbitrarily selected sets of specific models. We deal with static models (steady state and regression models), complex dynamic models (CAEDYM, CE-QUAL-W2, Delft 3D-ECO, LakeMab, LakeWeb, MyLake, PCLake, PROTECH, SALMO), structurally dynamic models and minimal dynamic models. We also discuss a group of approaches that could all be classified as individual based: super-individual models (Piscator, Charisma), physiologically structured models, stage-structured models and trait-based models. We briefly mention genetic algorithms, neural networks, Kalman filters and fuzzy logic. Thereafter, we zoom in, as an in-depth example, on the multi-decadal development and application of the lake ecosystem model PCLake and related models (PCLake Metamodel, Lake Shira Model, IPH-TRIM3D-PCLake). In the discussion, we argue that while the historical development of each approach and model is understandable given its 'leading principle', there are many opportunities for combining approaches. We take the point of view that a single 'right' approach does not exist and should not be strived for. Instead, multiple modelling approaches, applied concurrently to a given problem, can help develop an integrative view on the functioning of lake ecosystems. We end with a set of specific recommendations that may be of help in the further development of lake ecosystem models. В© 2010 The Author(s).

Scopus
Держатели документа:
Netherlands Institute of Ecology (NIOO-KNAW), Department of Aquatic Ecology, Rijksstraatweg 6, 3631 AC Nieuwersluis, Netherlands
Aarhus University, National Environmental Research Institute, Department of Freshwater Ecology, 8600 Silkeborg, Denmark
Greenland Climate Research Centre (GCRC), Greenland Institute of Natural Resources, Kivioq 2, P.O. Box 570, 3900 Nuuk, Greenland
University of Toronto, Department of Physical and Environmental Sciences, Toronto, ON M1C 1A4, Canada
Institute of Computational Modelling (SB-RAS), Siberian Federal University, 660036 Krasnoyarsk, Russian Federation
Tanzania Fisheries Research Institute (TAFIRI), Mwanza Centre, P.O. Box 475, Mwanza, Tanzania
Institute of Biophysics (SB-RAS), Akademgorodok, 660036 Krasnoyarsk, Russian Federation
University of Miami, Florida Integrated Science Centre, USGS, Coral Gables, FL 33124, United States
Wageningen University, Department of Aquatic Ecology and Water Quality, P.O. Box 47, 6700 AA Wageningen, Netherlands
Centre for Ecology and Hydrology, Lancaster Environment Centre, Lake Ecosystem Group, Algal Modelling Unit, Bailrigg, Lancaster LA1 4AP England, United Kingdom
Federal University of Alagoas, Centre for Technology, Campus A.C. Simoes, 57072-970 Maceio-AL, Brazil
Institute of Biochemistry and Biology, Department of Ecology and Ecosystem Modelling, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany
Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment, P.O. Box 7050, 75007 Uppsala, Sweden
University of Waikato, Centre for Biodiversity and Ecology Research, Private Bag 3105, Hamilton, New Zealand
University of Western Australia, School of Earth and Environment, Crawley, WA 6009, Australia
Technische Universitat Dresden, Institute of Hydrobiology, 01062 Dresden, Germany
Technische Universitat Dresden, Neunzehnhain Ecological Station, Neunzehnhainer Str. 14, 09514 Lengefeld, Germany
Deltares, P.O. Box 177, 2600 MH Delft, Netherlands
Technion-Israel Institute of Technology, Faculty of Civil and Environmental Engineering, Technicon City, Haifa 32000, Israel
Helmholtz Centre for Environmental Research, Department of Lake Research, Brueckstrasse 3a, 39114 Magdeburg, Germany
Witteveen and Bos, P.O. Box 233, 7400 AV Deventer, Netherlands
University of Oslo, Department of Biology, P.O. Box 1066, Blindern, 0316 Oslo, Norway
UNESCO-IHE Institute of Water Education, 2601 DA Delft, Netherlands
Portland State University, Department of Civil and Environmental Engineering, Portland, OR 97207, United States
Netherlands Environmental Assessment Agency (PBL), P.O. Box 303, 3720 AH Bilthoven, Netherlands : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Mooij, W.M.; Trolle, D.; Jeppesen, E.; Arhonditsis, G.; Belolipetsky, P.V.; Chitamwebwa, D.B.R.; Degermendzhy, A.G.; DeAngelis, D.L.; De Senerpont Domis, L.N.; Downing, A.S.; Elliott, J.A.; Fragoso Jr., C.R.; Gaedke, U.; Genova, S.N.; Gulati, R.D.; Hakanson, L.; Hamilton, D.P.; Hipsey, M.R.; 't Hoen, J.; Hulsmann, S.; Los, F.H.; Makler-Pick, V.; Petzoldt, T.; Prokopkin, I.G.; Rinke, K.; Schep, S.A.; Tominaga, K.; van Dam, A.A.; van Nes, E.H.; Wells, S.A.; Janse, J.H.

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3.


   
    Vertical stratification of physical, chemical and biological components in two saline lakes Shira and Shunet (South Siberia, Russia) / A. G. Degermendzhy [et al.] // Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - P619-632, DOI 10.1007/s10452-010-9336-6 . - ISSN 1386-2588
Кл.слова (ненормированные):
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).

Scopus
Держатели документа:
Institute of Biophysics SB RAS, 660036 Krasnoyarsk, Akademgorodok, Russian Federation
Siberian Federal University, Svobodnyi 79, 660041 Krasnoyarsk, Russian Federation
Netherlands Environmental Assessment Agency (PBL), P.O. Box 303, 3720 AH Bilthoven, Netherlands
Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), 3631 AC Nieuwersluis, Netherlands : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
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.

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4.


   
    A one-dimensional model of vertical stratification of Lake Shira focussed on winter conditions and ice cover / S. N. Genova [et al.] // Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - P571-584, DOI 10.1007/s10452-010-9327-7 . - ISSN 1386-2588
Кл.слова (ненормированные):
Convective mixed layer -- Ice formation -- Ice melting -- Simplified model -- Winter profiles -- anoxic conditions -- hydrogen sulfide -- ice cover -- inhomogeneity -- meromictic lake -- numerical model -- one-dimensional modeling -- pycnocline -- salinity -- seasonality -- stratification -- vertical profile -- water column -- water temperature -- Khakassia -- Lake Shira -- Russian Federation
Аннотация: In meromictic lakes such as Lake Shira, horizontal inhomogeneity is small in comparison with vertical gradients. To determine the vertical distribution of temperature, salinity, and density of water in a deep zone of a Lake Shira, or other saline lakes, a one-dimensional (in vertical direction) mathematical model is presented. A special feature of this model is that it takes into account the process of ice formation. The model of ice formation is based on the one-phase Stefan problem with the linear temperature distribution in the solid phase. A convective mixed layer is formed under an ice cover due to salt extraction in the ice formation process. To obtain analytical solutions for the vertical distribution of temperature, salinity, and density of water, we use a scheme of vertical structure in the form of several layers. In spring, the ice melts as top and bottom. These processes are taken into account in the model. The calculated profiles of salinity and temperature of Shira Lake are in good agreement with field measurement data for each season. Additionally, we focussed on the redox zone, which is the zone in which the aerobic layers of a water column meet the anaerobic ones. Hyperactivity of plankton communities is observed in this zone in lakes with hydrogen sulphide monimolimnion, and Lake Shira is among them. The location of the redox zone in the lake, which is estimated from field measurements, coincides with a sharp increase in density (the pycnocline) during autumn and winter. During spring and summer, the redox zone is deeper than the pycnocline. The location of pycnocline calculated with the hydro physical model is in good agreement with field measurement data. В© 2010 Springer Science+Business Media B.V.

Scopus
Держатели документа:
Institute of Computational Modeling SB RAS, Akademgorodok 50/44, Krasnoyarsk 660036, Russian Federation
Krasnoyarsk, Siberian Federal University, Institute of Mathematics, Svobodny 79, Krasnoyarsk 660041, Russian Federation
Institute of Biophysics SB RAS, Akademgorodok, Krasnoyarsk 660036, Russian Federation
Federal University, Institute of Mathematics, Svobodny 79, Krasnoyarsk 660041, Russian Federation
Netherlands Institute of Ecology, Center for Limnology, Rijksstraatweg 6, Nieuwersluis 3631 AC, Netherlands : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Genova, S.N.; Belolipetskii, V.M.; Rogozin, D.Y.; Degermendzhy, A.G.; Mooij, W.M.

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5.


   
    A general one-dimensional vertical ecosystem model of Lake Shira (Russia, Khakasia): Description, parametrization and analysis / I. G. Prokopkin [et al.] // Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - P585-618, DOI 10.1007/s10452-010-9326-8 . - ISSN 1386-2588
Кл.слова (ненормированные):
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.

Scopus
Держатели документа:
Institute of Biophysics, Akademgorodok, 660036 Krasnoyarsk, Russian Federation
Netherlands Institute of Ecology, Centre for Limnology, Rijksstraatweg 6, 3631 AC Nieuwersluis, Netherlands
Netherlands Environmental Assessment Agency (PBL), Postbus 303, 3720 AH Bilthoven, Netherlands : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Prokopkin, I.G.; Mooij, W.M.; Janse, J.H.; Degermendzhy, A.G.

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6.


   
    Some generalizations based on stratification and vertical mixing in meromictic Lake Shira, Russia, in the period 2002-2009 / D. Y. Rogozin [et al.] // Aquatic Ecology. - 2010. - Vol. 44, Is. 3. - P485-496, DOI 10.1007/s10452-010-9328-6 . - ISSN 1386-2588
Кл.слова (ненормированные):
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).

Scopus
Держатели документа:
Institute of Biophysics of Siberian Branch of Russian Academy of Sciences, Akademgorodok 50-50, 660036 Krasnoyarsk, Russian Federation
Siberian Federal University, Svobodny 79, 660071 Krasnoyarsk, Russian Federation
Institute of Computational Modeling of Siberian Branch of Russian Academy of Sciences, Akademgorodok 50-50, 660036 Krasnoyarsk, Russian Federation
The Netherlands Institute of Ecology, Center for Aquatic Ecology, Nieuwersluis, Netherlands : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Rogozin, D.Y.; Genova, S.N.; Gulati, R.D.; Degermendzhy, A.G.

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7.


   
    Understanding the mechanisms of blooming of phytoplankton in Lake Shira, a saline lake in Siberia (the Republic of Khakasia) / A. G. Degermendzhy, R. D. Gulati // Aquatic Ecology. - 2002. - Vol. 36, Is. 2. - P331-340 . - ISSN 1386-2588
Кл.слова (ненормированные):
Carbon budget -- Cyanobacteria -- Heterotrophic bacteria -- Hydrogen sulphide -- Mathematical models of stratification -- Meromictic lakes -- Microbial loop -- Stratification -- Trophic scheme -- algal bloom -- ecosystem modeling -- limiting factor -- nutrient availability -- phytoplankton -- saline lake -- trophic interaction -- Russian Federation -- algae -- Bacteria (microorganisms) -- Cyanobacteria -- Lyngbya -- Lyngbya contorta
Аннотация: The paper summarises the results of a three-year research study (European Union Grant: INTAS 97-0519) aimed at investigating the planktonic populations and trophic organization of the Lake Shira ecosystem - a saline lake in Khakasia, Siberia. The lake exhibits a stable summer-autumn stratification of the chemical-biological components. The mechanisms responsible for the 'blooming' of phytoplankton in the deeper layers were investigated in greater detail, using data from both field and laboratory experiments. The spectra of nutrition were examined to estimate the relationships between the specific growth rates of the hydrobionts and the influence of the limiting factors: light, nutrients. The observed heterotrophic capability of a metalimnetic phytoplankton population might help explain the development in the deeper waters of Lyngbya contorta. The scheme of trophic interactions was put up, based on the assessment of the carbon pools and carbon flows in the pelagic zone of the lake. A mathematical model of the vertical structure of the lake's plankton populations was constructed, using the ecosystem description and data of vertical turbulent diffusion. The role of light and nutrient limitations and grazing mortality in forming the vertical inhomogeneities, particularly in lowering the depth of the maximal cyanobacterial biomass, has been demonstrated. The theoretical curves for the stratification of chemical and biological parameters have been brought in conformity with the field observations, e.g. for the different patterns of the peaks, and for the biomass maxima of cyanobacteria, purple and green sulphur bacteria, oxygen, and hydrogen sulphide. The calculations revealed that for an adequate assessment of the parameters for the hydrogen sulphide zone it is necessary to introduce flows of allochthonous organic matter. Based on the form of the sulphur distribution curve, the allochthonous input of organic matter and the inflow of hydrogen sulphide from the bottom have been theoretically discriminated for the first time. It has also been ascertained that irrespective of the depth the allochthonous substances limiting bacterial growth, the bacteria are uniformly distributed over depth and can serve as an indicator of the presence of limitation (the effect of autostabilisation in space). Of indisputable interest to limnology are the specific methods developed for understanding the functioning of Lake Shira ecosystem. These include the autostabilisation of the limiting factors, the on-the-spot fluorescent method of determining the three classes of microalgae, the algal mixotrophy and the planktonic population interactions and feedbacks, and development of a more sensitive, bioluminescent method for mapping the nonhomogeneities. Owing to a balanced combination of classical approaches (field observations, in situ data on production-decomposition) and the more recent ones (satellite monitoring, biophysical methods of estimating interactions of populations, mathematical models based on the field and experimental data), many of the structural-function relationships in the ecosystem can now be explained, and the models can provide 'mutual control and mutual agreement' between the data collected using different approaches.

Scopus
Держатели документа:
Institute of Biophysics SB RAS, 660036 Krasnoyarsk, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Degermendzhy, A.G.; Gulati, R.D.

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8.


   
    Formation of the vertical heterogeneity in the Lake Shira ecosystem: The biological mechanisms and mathematical model / A. G. Degermendzhy [et al.] // Aquatic Ecology. - 2002. - Vol. 36, Is. 2. - P271-297, DOI 10.1023/A:1015621508971 . - ISSN 1386-2588
Кл.слова (ненормированные):
Hydrogen sulphide -- Phytoplankton -- Stratification control -- Sulphate-reducing bacteria -- Sulphur cycle -- Vertical model -- biological production -- community structure -- ecosystem modeling -- nutrient cycling -- plankton -- saline lake -- seasonal variation -- vertical distribution -- Russian Federation -- algae -- Arctodiaptomus -- Bacteria (microorganisms) -- Calanoida -- Chlorophyta -- Copepoda -- Crustacea -- Cyanobacteria -- Dictyosphaerium -- Lyngbya -- Lyngbya contorta
Аннотация: Data on the seasonal changes in vertical heterogeneity of the physical-chemical and biological parameters of the thermally stratified Shira Lake ecosystem (Khakasia, Siberia) in 1996-2000 have been analyzed. The interaction mechanisms involving: (1) The plankton populations in aerobic and anaerobic zones, involving the cycling of carbon and sulphur, (2) the primary production limitation (by light and phosphorus) and inhibition (by light), and (3) the kinetic characteristics of plankton populations have been elucidated. A mathematical model of the vertical structure of the lake's plankton populations, based on the ecosystem description and on vertical turbulent diffusion of the matter, has been constructed. The green alga Dictyosphaerium tetrachotomum (Chlorophyta) and the cyanobacterium Lyngbya contorta (Cyanophyta), which dominated the phytoplankton biomass, were taken as oxygen producers. Arctodiaptomus salinus (a calanoid copepod) has been assumed as the main grazer in Shira Lake as it dominated the zooplankton biomass. Four groups of microorganisms involved in the sulphur cycle formation have been distinguished: sulphur, sulphur purple, sulphur green and SRB. H2S is oxidized to sulphate (only the green sulphur bacteria oxidize it to sulphur), and sulphate is reduced to H2S, forming neither sulphur nor its water-soluble compounds. The role of grazing, light and nutrient limitation, in forming the vertical inhomogeneities, particularly in lowering the depth of the maximal cyanobacterial biomass, has been demonstrated. When the model takes into account both light limitation and nutrient limitation of algal growth by P and consumption of algae by crustaceans: (a) in the scenario where the P is formed only by the cycling and decomposition of autochthonous organic matter, both the green algae and cyanobacteria are eliminated; (b) in the scenario involving an additional P flux in the deep water layers the peak of the cyanobacteria is at a depth of 10 m, and its amplitude is close to the one observed in the lake. The position of the peak remains stable owing to the 'double' limitation mechanism: light 'from above' and P 'from below'. Another mechanism responsible for the deep position of the peak of cyanobacteria was analyzed mathematically based on the model involving the experimentally proven assumption of the growth inhibition by light in the epilimnion and the light limitation in the hypolimnion. The main result is: the peak is positioned stable at its depth and does not change with time. The analytical and numerical calculations made for this positioning mechanism yielded the formulae relating the depth of the maximum of algal biomass, the 'width' of the peak base and the peak amplitude and a number of parameters (algae elimination, turbulent diffusion coefficient, sedimentation rate, light extinction coefficient and light intensity). The theoretical curves for the stratification of chemical and biological parameters have been brought in conformity with field observations, e.g. for the different patterns for the peaks, and the biomass maxima of cyanobacteria, purple and green sulphur bacteria, oxygen, and hydrogen sulphide. The calculations revealed that for an adequate assessment of the parameters for the hydrogen sulphide zone it is necessary to introduce flows of allochthonous organic matter. For the first time, theoretically, based on the form of the sulphur distribution curve, the allochthonous input of organic matter and the inflow of hydrogen sulphide from the bottom have been discriminated. The theoretical limit for the depth up to which the hydrogen-sulphide zone can ascend under the impact of allochthonous organic loading, has been determined.

Scopus
Держатели документа:
Institute of Biophysics of SB RAS, Krasnoyarsk 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Degermendzhy, A.G.; Belolipetsky, V.M.; Zotina, T.A.; Gulati, R.D.

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9.


   
    Agent-based modeling of the complex life cycle of a cyanobacterium (Anabaena) in a shallow reservoir / F. L. Hellweger [et al.] // Limnology and Oceanography. - 2008. - Vol. 53, Is. 4. - P1227-1241 . - ISSN 0024-3590
Кл.слова (ненормированные):
algal bloom -- annual variation -- cyanobacterium -- ecological modeling -- Eulerian analysis -- experimental study -- Lagrangian analysis -- life cycle -- nutrient availability -- phytoplankton -- population dynamics -- reservoir -- shallow water -- survival -- water column -- Bugach Reservoir -- Eurasia -- Krasnoyarsk [Russian Federation] -- Russian Federation -- Anabaena -- Anabaena flos-aquae
Аннотация: The cyanobacterium Anabaena flos-aquae and many other phytoplankton species have a complex life cycle that includes a resting stage (akinete). We present a new agent-based (also known as individual-based) model of Anabaena that includes the formation and behavior of akinetes. The model is part of a coupled Eulerian-Lagrangian model and can reproduce the main features of the observed seasonal and interannual population dynamics in Bugach Reservoir (Siberia), including an unexpectedly large bloom in a year with low nutrient concentrations. Model analysis shows that the internal loading of phosphorus (P) due to germination from the sediment bed is ?10% of the total input. However, most of the long-term nutrient uptake for Anabaena occurs in the sediment bed, which suggests that the sediment bed is not just a convenient overwintering location but may also be the primary source of nutrients. An in silico tracing experiment showed that most water column cells (?90%) originated from cells located in the sediment bed during the preceding winter. An in silico gene knockout experiment (akinete formation is prohibited) showed that the formation of resting stages is of critical importance to the survival of the population on an annual basis. A nutrient-reduction management scenario indicates that Anabaena densities increase because they are less sensitive to water column nutrient levels (because of the sediment bed source) than other species. В© 2008, by the American Society of Limnology and Oceanography, Inc.

Scopus
Держатели документа:
Civil and Environmental Engineering Department, Northeastern University, Boston, MA 02115, United States
Center for Urban Environmental Studies, Northeastern University, Boston, MA 02115, United States
Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk 660036, Russian Federation
Siberian Federal University, Krasnoyarsk 660041, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Hellweger, F.L.; Kravchuk, E.S.; Novotny, V.; Gladyshev, M.I.

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10.


   
    Modelling the effect of planktivorous fish removal in a reservoir on the biomass of cyanobacteria / I. G. Prokopkin, V. G. Gubanov, M. I. Gladyshev // Ecological Modelling. - 2006. - Vol. 190, Is. 3-4. - P419-431, DOI 10.1016/j.ecolmodel.2005.05.011 . - ISSN 0304-3800
Кл.слова (ненормированные):
Biomanipulation -- Cyanobacteria -- Ecological mathematical model -- Viable gut passage -- Bacteria -- Biodiversity -- Biomass -- Ecosystems -- Rivers -- Cyanobacteria -- Fishes -- Viable gut passage -- Ecology -- algal bloom -- community dynamics -- modeling -- planktivore -- removal experiment -- reservoir -- Bugach Reservoir -- Eastern Hemisphere -- Eurasia -- Krasnoyarsk [Russian Federation] -- Russian Federation -- World -- Anabaena -- Carassius auratus -- Carassius carassius -- Cyanobacteria -- Cyprinus carpio -- Daphnia -- Microcystis
Аннотация: In 2002, a "top-down" biomanipulation (reduction of biomass of planktivorous fish Carassius auratus) had been successfully carried out in a small reservoir of the river Bugach (Krasnoyarsk, Russia), after which the cyanobacterial blooming ceased. However, the reservoir ecosystem was absolutely free of Daphnia - the main link of trophic cascade. As supposed, the reduction of blooming was the result of suppression of a direct stimulation effect of planktivorous fish on cyanobacteria, revealed earlier in laboratory experiments. The question arose as to whether the effect of stimulation of cyanobacteria revealed in laboratory may lead to the changes in biomass of cyanobacteria in the reservoir, observed after the biomanipulation. To test this supposition, a mathematical model describing growth of cyanobacteria in the reservoir was developed. The modelling results and field data on biomass of cyanobacteria in summer closely coincided. Modelling calculations showed that direct influence of planktivorous fish could cause the second summer peak of water blooming by Microcystis. On the contrary, removal of crucian carp from the reservoir will not affect the level of water blooming caused by cyanobacteria Anabaena, as this species' growth is not stimulated by fish. В© 2005 Elsevier B.V. All rights reserved.

Scopus
Держатели документа:
Institute of Biophysics, Akademgorodok, 660036 Krasnoyarsk, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Prokopkin, I.G.; Gubanov, V.G.; Gladyshev, M.I.

Найти похожие
11.


   
    Individual-based model of the reproduction cycle of Moina macrocopa (Crustacea: Cladocera) / E. S. Zadereev [et al.] // Ecological Modelling. - 2003. - Vol. 162, Is. 1-2. - P15-31, DOI 10.1016/S0304-3800(02)00348-4 . - ISSN 0304-3800
Кл.слова (ненормированные):
Change of reproduction mode -- Cladocera -- Individual-based model -- Metabolic by-products -- ecological modeling -- individual-based model -- reproductive cycle -- Animalia -- Cladocera -- Crustacea -- Moina macrocopa
Аннотация: An individual-based model of cyclic development of Cladocera populations was developed on the basis of experimental data. The model takes into account the following processes describing the development of an individual animal: maturation, transition into other reproductive classes, selection of the reproduction mode (parthenogenetic or gamogenetic), release of parthenogenetic progeny and death. The model assumes that switching from asexual to sexual reproduction is controlled by the concentration of food and metabolic by-products of the animal population. Verification of the model by independent experiments demonstrated that (1) during population growth, metabolic by-products build up in the medium, and (2) the effect of metabolic by-products on gamogenesis induction depends on concentration. The hypothesis that the effect of regulating reproductive switching factors should synchronise the development of population with the change of environmental conditions in order to ensure production of the maximum number of diapausing eggs was tested. It is shown that combination of regulating reproductive switching factors maximises the production of diapausing eggs. В© 2002 Elsevier Science B.V. All rights reserved.

Scopus
Держатели документа:
Institute of Biophysics, Akademgorodok, 660036 Krasnoyarsk, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Zadereev, E.S.; Prokopkin, I.G.; Gubanov, V.G.; Gubanov, M.V.

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12.


   
    Typification of natural seasonal dynamics of vegetation to reveal impact of land surface change on environment (by satellite data) / A. Shevyrnogov [et al.] // Advances in Space Research. - 2000. - Vol. 26, Is. 7. - P1169-1172, DOI 10.1016/S0273-1177(99)01142-4 . - ISSN 0273-1177
Кл.слова (ненормированные):
ecological modeling -- ecosystem health -- land surface -- satellite data -- vegetation dynamics
Аннотация: Deep insight into types of vegetation variability provided by AVHRR space scanner images of vegetation index spatial distribution helps reveal impact of land surface changes on environment. The Institute of Computational Modeling SB RAS has developed nonparametric algorithms of automatic to classify and recognize patterns of these images which helped to reveal: (1) major variability types (generally connected); (2) areas belonging to small classes, which can be used to reveal deviations from 'normal' (e.g., forest fires, etc.); (3) deviation from a certain type of dynamics indicative of changes in condition of plants, which can be used to diagnose pathology at early stages; (4) impact of economical activities on vegetation in Norilsk area. The authors provide biological interpretation of the satellite data. Computer-animated dynamics and color maps are presented. Nonparametric algorithms of an automatic classification and pattern recognition were provided by the Institute of Computational Modeling SB RAS. (C) 2000 COSPAR. Published by Elsevier Science Ltd.

Scopus
Держатели документа:
Inst. of Biophys. of Russ. A., Siberian Branch, 660036, Krasnoyarsk, Russian Federation
Inst. of Compl. Modeling of Russ. A., Siberian Branch (SB RAS), 660036, Krasnoyarsk, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Shevyrnogov, A.; Vysotskaya, G.; Sidko, A.; Dunaev, K.

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13.


   
    Mass exchange in an experimental new-generation life support system model based on biological regeneration of environment / A. A. Tikhomirov [et al.] // Advances in Space Research. - 2003. - Vol. 31, Is. 7. - P1711-1720, DOI 10.1016/S0273-1177(03)80017-0 . - ISSN 0273-1177
Кл.слова (ненормированные):
Biomass -- Photosynthesis -- Plants (botany) -- Transpiration -- Mass exchange -- Life support systems (spacecraft) -- ammonia -- nitrogen -- oxygen -- biosphere -- animal -- annelid worm -- article -- biological model -- biomass -- bioremediation -- evaluation -- growth, development and aging -- human -- metabolism -- microclimate -- photosynthesis -- Pleurotus -- radish -- wheat -- Ammonia -- Animals -- Biodegradation, Environmental -- Biomass -- Ecological Systems, Closed -- Evaluation Studies -- Humans -- Life Support Systems -- Models, Biological -- Nitrogen -- Oligochaeta -- Oxygen -- Photosynthesis -- Pleurotus -- Raphanus -- Triticum
Аннотация: An experimental model of a biological life support system was used to evaluate qualitative and quantitative parameters of the internal mass exchange. The photosynthesizing unit included the higher plant component (wheat and radish), and the heterotrophic unit consisted of a soil-like substrate, California worms, mushrooms and microbial microflora. The gas mass exchange involved evolution of oxygen by the photosynthesizing component and its uptake by the heterotroph component along with the formation and maintaining of the SLS structure, growth of mushrooms and California worms, human respiration, and some other processes. Human presence in the system in the form of "virtual human" that at regular intervals took part in the respirative gas exchange during the experiment. Experimental data demonstrated good oxygen/carbon dioxide balance, and the closure of the cycles of these gases was almost complete. The water cycle was nearly 100% closed. The main components in the water mass exchange were transpiration water and the watering solution with mineral elements. Human consumption of the edible plant biomass (grains and roots) was simulated by processing these products by a unique physicochemical method of oxidizing them to inorganic mineral compounds, which were then returned into the system and fully assimilated by the plants. The oxidation was achieved by "wet combustion" of organic biomass, using hydrogen peroxide following a special procedure, which does not require high temperature and pressure. Hydrogen peroxide is produced from the water inside the system. The closure of the cycle was estimated for individual elements and compounds. Stoichiometric proportions are given for the main components included in the experimental model of the system. Approaches to the mathematical modeling of the cycling processes are discussed, using the data of the experimental model. Nitrogen, as a representative of biogenic elements, shows an almost 100% closure of the cycle inside the system. The proposed experimental model of a biological system is discussed as a candidate for potential application in the investigations aimed at creating ecosystems with largely closed cycles of the internal mass exchange. The formation and maintenance of sustainable cycling of vitally important chemical elements and compounds in biological life support systems (BLSS) is an extremely pressing problem. To attain the stable functioning of biological life support systems (BLSS) and to maintain a high degree of closure of material cycles in them, it is essential to understand the character of mass exchange processes and stoichiometric proportions of the initial and synthesized components of the system. В© 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Scopus
Держатели документа:
Institute of Biophysics, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk, Russian Federation
Universite B. Pascal, Clermont-Ferrand, France
Environ. Control/Life Support Sect., ESA, Estec Noorwijk, Netherlands : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Tikhomirov, A.A.; Ushakova, S.A.; Manukovsky, N.S.; Lisovsky, G.M.; Kudenko, Yu.A.; Kovalev, V.S.; Gubanov, V.G.; Barkhatov, Yu.V.; Gribovskaya, I.V.; Zolotukhin, I.G.; Gros, J.B.; Lasseur, Ch.

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14.


   
    A closed ecological system as a means of providing high quality of life in an antarctic station and as a model of a life-support system for the martian mission / J. I. Gitelson [et al.] // International Astronautical Federation - 55th International Astronautical Congress 2004. - 2004. - Vol. 3: International Astronautical Federation - 55th International Astronautical Congress 2004 (4 October 2004 through 8 October 2004, Vancouver) Conference code: 69653. - P1428-1435
Кл.слова (ненормированные):
Biotechnology -- Environmental impact -- Martian surface analysis -- Photosynthesis -- Psychophysiology -- Water pollution -- Antarctic station -- Closing technology -- Ecological life support system -- Environmental pollution -- Ecosystems
Аннотация: This closing technology developed for experimental BIOS-3 facility seems to be highly expedient for providing normal life conditions in high-latitude settlements and first of all for life-support of Antarctic stations. Obvious advantages of ecological life-support system based on photosynthesis, in comparison with used now in Antarctic Continent, are: 1) highly effective cascade usage of energy for performance of all functions of life-support; 2) minimization of environmental pollution due to processing human excretions and polluted water; 3) providing crew with fresh vegetable food all-the-year-round; 4) contact with alive plants is powerful source of positive emotions and effective means of psychological relaxation; 5) significant reduction of the transport charges on delivery of foodstuff to Antarctic Continent. First of all, the usage of closed ecosystem can be recommended for high-mountainous station "Concordia". Similar ecosystems can be used in northern high-latitude settlements - Russian North, Canadian Northern territories, Alaska. Finally, the experience of closed ecological life-support system operation in Antarctic Continent can serve as the best range for modeling some aspects of Martian mission - its ecological, biotechnological and psychophysiological problems - since there are no natural conditions on the Earth closer to Mars with respect to severity of a place.

Scopus
Держатели документа:
Institute of Biophysics, SB, RAS, Krasnoyarsk, 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Gitelson, J.I.; Bartsev, S.I.; Okhonin, V.A.; Mezhevikin, V.V.

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15.


   
    Kinetic characteristics of the theoretical ecosystems with different extent of openness / Ya. V. Galayda [et al.] // Advances in Space Research. - 2005. - Vol. 35, Is. 9 SPEC. ISS. - P1516-1520, DOI 10.1016/j.asr.2005.01.034 . - ISSN 0273-1177
Кл.слова (ненормированные):
Mathematic modeling -- Net primary production -- Residual concentration of biogenic limiting substances -- Trophic chain length -- Mathematic modeling -- Net primary production -- Residual concentration of biogenic limiting substances -- Trophic chain length -- Characterization -- Degradation -- Kinetic theory -- Mathematical models -- Nitrogen -- Phosphorus -- Recycling -- Surface waters -- Ecosystems -- biological model -- biomass -- bioremediation -- conference paper -- ecosystem -- food chain -- microclimate -- Biodegradation, Environmental -- Biomass -- Ecological Systems, Closed -- Ecosystem -- Food Chain -- Life Support Systems -- Models, Biological
Аннотация: In this paper, the influence of the extent of openness of ecosystem that is defined by the dilution rate, which characterizes the extent of flowage of the pond, on the intensity of the biotic circulation in ecosystems with different regulation types, number of trophic links and extent of closing has been investigated. We considered open systems, we took into account the return of the limiting substances, such as nitrogen and phosphorous, into the cycle by degradation of detritus and products of vital functions of consumers. It was shown by the numerical calculations that the increase of the dilution rate in without recycle ecosystems leads to increase of the net primary production up to the maximum value corresponding to the two-link trophic chain (biogenic substance and producer) and then, to gradually decrease. The residual concentration of biogenic limiting substances monotone increases. Net primary production and residual concentration of biogenic limiting substances in systems with recycle with even number of links behaves similarly to that in without recycle ecosystems. In the systems with recycle with the odd number of links that values lies on the stable level. We showed that in wide range of the dilution rate the recycling of the ecosystem can highly increase the net primary production and reduce residual concentration of biogenic limiting substances. The influence of the dilution rate on numbers of links that may exist in the system was analyzed. В© 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.

Scopus
Держатели документа:
Krasnoyarsk State University, Svobodny 79, Krasnoyarsk 660041, Russian Federation
Institute of Biophysics, SB, RAS, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Galayda, Ya.V.; Pechurkin, N.S.; Shirobokova, I.M.; Pisman, T.I.

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16.


   
    The effect of cannibalism intensity on net primary production and dynamics of trophic links in aquatic ecosystems / I. M. Shirobokova, N. S. Pechurkin // Advances in Space Research. - 2003. - Vol. 31, Is. 7. - P1737-1741, DOI 10.1016/S0273-1177(03)00112-1 . - ISSN 0273-1177
Кл.слова (ненормированные):
Biomass -- Ecosystems -- Mathematical models -- Photosynthesis -- Cannibalism intensity -- Space research -- aquatic ecosystem -- cannibalism -- ecological modeling -- net primary production -- trophic structure -- Amphipoda -- animal -- aquaculture -- article -- biological model -- biomass -- cannibalism -- Daphnia -- ecosystem -- food chain -- microclimate -- phytoplankton -- zooplankton -- Amphipoda -- Animals -- Aquaculture -- Biomass -- Cannibalism -- Daphnia -- Ecological Systems, Closed -- Ecosystem -- Food Chain -- Models, Biological -- Phytoplankton -- Zooplankton
Аннотация: A mathematical model was used to investigate the effect of cannibalism intensity on the net primary production and the dynamics of trophic links in an aquatic ecosystem characterized by cannibalism at the upper trophic level. A mathematical model of an aquatic ecosystem has been constructed, with the following principal trophic links: limiting nutrient concentration, producers (phytoplankton), nonpredatory and predatory zooplankton. The model takes into account the age structure of the predator and includes two age groups (the young and adults). The adult predators are cannibals feeding on both nonpredatory zooplankton and their own young, which consume phytoplankton. It has been found that when cannibalism intensity increases above a certain level, the concentrations of both adults and the young of the predators decrease. At the same time, the concentrations of the nonpredatory zooplankton and of nutrients increase, while the biomass of producers decreases. When the cannibalism intensity is low, the net primary production of the system increases to a certain level correlated with the increase in cannibalism intensity and drops sharply when the level of consumption of young is high. There is an optimal intensity of cannibalism, at which the productivity in the photosynthesis link is maximal. В© 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Scopus
Держатели документа:
Inst. of Biophys. of Siberian Branch, Russian Academy of Sciences, Krasnoyarsk 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Shirobokova, I.M.; Pechurkin, N.S.

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17.


   
    System analysis of links interactions and development of ecosystems of different types / N. S. Pechurkin, I. M. Shirobokova // Advances in Space Research. - 2003. - Vol. 31, Is. 7. - P1667-1674, DOI 10.1016/S0273-1177(03)80013-3 . - ISSN 0273-1177
Кл.слова (ненормированные):
Free energy -- Heuristic methods -- Hierarchical systems -- Mathematical models -- Photosynthesis -- Systems analysis -- Biological interactions -- Ecosystems -- anthropogenic effect -- ecosystem function -- systems analysis -- article -- biological model -- biomass -- ecology -- ecosystem -- energy transfer -- environmental protection -- food chain -- methodology -- microclimate -- plankton -- population dynamics -- statistics -- Biomass -- Conservation of Natural Resources -- Ecological Systems, Closed -- Ecology -- Ecosystem -- Energy Transfer -- Food Chain -- Models, Biological -- Plankton -- Population Dynamics
Аннотация: The anthropogenic impact on the Earth's ecosystems are leading to dramatic changes in ecosystem functioning and even to destruction of them. System analysis and the use of heuristic modeling can be an effective means to determine the main biological interactions and key factors that are of high importance for understanding the development of ecosystems. Cycling of limiting substances, induced by the external free energy flux, and trophic links interaction is the basis of the mathematical modeling studies presented in this paper. Mathematical models describe the dynamics of simplified ecosystems having different characteristics: 1) different degrees of biotic turnover closure (from open to completely closed); 2) different numbers of trophic links (including both "topdown", "bottom-up" regulation types); 3) different intensities of input - output flows of the limiting nutrient and its total amount in the system. Adaptive values of the changes of lower hierarchical levels (populational, trophic chain level) are to be estimated by integrity indices for total system functioning (e.g. NPP, total photosynthesis). The approach developed can be used for evaluating the contributions of lower hierarchical levels to the functioning of the higher hierarchical levels of the system. This approach may have value for determining biomanipulation management and their assessment. В© 2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Scopus
Держатели документа:
Institute of Biophysics, SB RAS, Krasnoyarsk 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Pechurkin, N.S.; Shirobokova, I.M.

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18.


   
    Mathematical modeling of response of ecosystems with different structure to external impact / I. M. Shirobokova, N. S. Pechurkin // Advances in Space Research. - 2001. - Vol. 27, Is. 9. - P1593-1598, DOI 10.1016/S0273-1177(01)00254-X . - ISSN 0273-1177
Кл.слова (ненормированные):
Environmental impact -- Mathematical models -- Sensitivity analysis -- Structural analysis -- Top-down controlled systems -- Ecosystems -- fresh water -- ecosystem response -- animal -- article -- biological model -- biomass -- ecosystem -- Escherichia coli -- food chain -- microclimate -- protozoon -- Animals -- Biomass -- Ecological Systems, Closed -- Ecosystem -- Escherichia coli -- Food Chain -- Fresh Water -- Models, Biological -- Protozoa
Аннотация: A mathematical model was used to study the response of ecosystems of different structures to external impact. The response was measured as a sensitivity coefficient: the magnitude of the system's response vs. the change of the factor in the inflow. The formula has been obtained to calculate the sensitivity coefficient for ecosystems containing different numbers of trophic links. The derived sensitivity coefficients demonstrate that the degree of compensation for the external impact can differ depending on the type of system regulation and the length of the trophic chain. E. g. the sensitivity coefficient decreases with complexity of trophic links in an ecosystem for top-down controlled systems and impact of degree of openness on sensitivity e.g. closed ecosystems show higher sensitivity then fully open ecosystem to impacts also bottom-up control system show less sensitivity then top-down. В© 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Scopus
Держатели документа:
Institute of Biophysics, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Shirobokova, I.M.; Pechurkin, N.S.

Найти похожие
19.


   
    Computer modeling of the biotic cycle formation in a closed ecological system / A. V. Brilkov [et al.] // Advances in Space Research. - 2001. - Vol. 27, Is. 9. - P1587-1592, DOI 10.1016/S0273-1177(01)00253-8 . - ISSN 0273-1177
Кл.слова (ненормированные):
Ecology -- Energy utilization -- Mathematical models -- Biotic turnover -- Predators -- Space research -- artificial ecosystem -- alga -- animal -- article -- biological model -- computer simulation -- Cyprinodontiformes -- Daphnia -- ecosystem -- energy metabolism -- evolution -- food chain -- microclimate -- plankton -- Algae -- Animals -- Computer Simulation -- Daphnia -- Ecological Systems, Closed -- Ecosystem -- Energy Metabolism -- Evolution -- Food Chain -- Models, Biological -- Plankton -- Poecilia
Аннотация: The process of biotic turnover in a closed ecological system (CES) with an external energy flow was analyzed by mathematical modeling of the biotic cycle formation. The formation of hierarchical structure in model CESs is governed by energy criteria. Energy flow through the ecosystem increases when a predator is introduced into a "producer-reducer" system at steady state. Analysis of the model shows that under certain conditions the presence of the primary predator with its high mineralization ability accelerates the biotic turnover measured by primary production. We, therefore, conclude that for every system it is possible to find a suitable predator able to provide the system with a higher biotic turnover rate and energy consumption. В© 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Scopus
Держатели документа:
Institute of Biophysics, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk, 660036, Russian Federation : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Brilkov, A.V.; Ganusov, V.V.; Morozova, E.V.; Pechurkin, N.S.

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20.


   
    Mathematical modeling of population dynamics of unstable plasmid-containing bacteria during continuous cultivation in a chemostat / V. V. Ganusov, A. V. Bril'kov, N. S. Pechurkin // Biofizika. - 2000. - Vol. 45, Is. 5. - С. 908-914 . - ISSN 0006-3029
Кл.слова (ненормированные):
article -- bioreactor -- Escherichia coli -- fermentation -- genetics -- growth, development and aging -- Photobacterium -- plasmid -- theoretical model -- Bioreactors -- Escherichia coli -- Fermentation -- Models, Theoretical -- Photobacterium -- Plasmids
Аннотация: A structural approach to studying the regularities of the population dynamics of unstable recombinant bacterial strains in a chemostat was elaborated. The approach is based on the mathematical modeling of cell distribution in a population with different numbers of plasmid copies. The effect of decreased selective preference of plasmidless variants of the recombinant strain in the chemostat, which is related to a decrease in the number of plasmid copies in cells upon long-term incubation was analyzed. It is shown that the time of half-elimination of plasmids from the bacterial population in the steady state in the chemostat T1/2 does not depend on the maximum number of plasmid copies in cells N but is determined only by the mean time of generation g and the probability of the loss of one plasmid copy tau. The dependence of the preference of bacterial plasmidless variants on the efficiency of expression of genes cloned into plasmids in chemostat was analyzed using the recombinant strain E. coli Z905, whose plasmids pPHL-7 contain cloned genes for the luminescence system of marine luminescing bacteria Photobacterium leiognathi.

Scopus
Держатели документа:
Institute of Biophysics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, Russia. : 660036, Красноярск, Академгородок, д. 50, стр. 50

Доп.точки доступа:
Ganusov, V.V.; Bril'kov, A.V.; Pechurkin, N.S.

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