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1.
Biofizika ; 60(2): 411-5, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26016039

RESUMO

The paper presents the idea of transparent evolution through the long-term reaction of the planet Earth on the external flow of radiant energy from the Sun. Due to limitations of matter on Earth, as well as on any other planet, the continuous pumping flow of radiant energy was shown to lead to cyclization and transport of substance on emerging gradients. The evolution of energy-matter interaction follows the path of capturing and transferring more energy by the fewer matter, i.e., the path of growth of the amount of energy used by each unit mass. For this indicator, the least effective mass transfer is a simple mass transfer as vortices of gases, in the gradients of temperature and pressure, which occurred on the primary surface of the planet. A long-term natural selection related to the accumulation of water on the planet has played a special role in developing the interaction of energy and matter. Phase transformations (ice, water, vapor) and mechanical transfers are the most common energy-matter processes. Based on water cycles, cyclic transports and transformations, chemical transformation of substances became possible developing over time into a biological transformation. This kind of the interaction of energy and matter is most efficient. In particular, during photosynthesis the energy of our star "is captured and utilized" in the most active part of the spectrum of its radiation. In the process of biological evolution of heterotrophs, a rise (by a factor of hundreds) in the coefficient that characterizes the intensity of energy exchange from protozoa to mammals is most illustratory. The development and the current dominance of humans as the most energy-using active species in capturing the energy and meaningful organization of its new flows especially on the basis of organic debris of former biospheres is admirable, but quite natural from the energy positions. In the course of technological evolution of humankind, the measure of the intensity of energy for homoeothermic (warm-blooded) animals has increased 20 times, based on the process energy used by the "average" inhabitant of the world. Thus, the victory of our species in planetary evolution is easy to fit into the mainstream of evolution through energy-matter interactions: multiple growth of star energy was used to transform the matter on the surface of the irradiated planet.


Assuntos
Evolução Biológica , Planeta Terra , Fotossíntese , Sistema Solar , Animais , Civilização , Metabolismo Energético , Humanos
3.
Adv Space Res ; 35(9): 1573-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16175684

RESUMO

Populations of Escherichia coli Z905/pPHL7, a transgenic microorganism, were heterogenic in the expression of plasmid genes when adapting to the conditions of water microcosms of various mineralization levels and structure of microbial community. This TM has formed two subpopulations (ampicillin-resistant and ampicillin-sensitive) in every microcosm. Irrespective of mineralization level of a microcosm, when E. coli Z905/pPHL7 alone was introduced, the ampicillin-resistant subpopulation prevailed, while introduction of the TM together with indigenous bacteria led to the dominance of the ampicillin-sensitive subpopulation. A high level of lux gene expression maintained longer in the freshwater microcosms than in sterile saline lake water microcosms. A horizontal gene transfer has been revealed between the jointly introduced TM and Micrococcus sp. 9/pSH1 in microcosms with the Lake Shira sterile water.


Assuntos
Ecossistema , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/genética , Dinâmica Populacional , Resistência a Ampicilina/genética , Microbiologia Ambiental , Água Doce , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Micrococcus/genética , Micrococcus/crescimento & desenvolvimento , Organismos Geneticamente Modificados , Plasmídeos/genética , Sais , Microbiologia da Água
4.
Adv Space Res ; 35(9): 1621-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16175696

RESUMO

The problem of interaction between man and microorganisms in closed habitats is an inextricable part of the whole problem of co-existence between macro- and microorganisms. Concerning the support of human life in closed habitat, we can, conventionally, divide microorganisms, acting in life support system (LSS) into three groups: useful, neutral and harmful. The tasks, for human beings for optimal coexistence with microhabitants seem to be trivial: (1) to increase the activity of useful forms, (2) decrease the activity harmful forms, (3) not allow the neutral forms to become the harmful ones and even to help them to gain useful activity. The task of efficient management and control of microbial population's development in LSS highly depends on mission duration. As for short-term missions without recycling, the proper hygienic procedures are developed. For longer missions, the probability of transformation of the neutral forms into the harmful ones is becoming more dangerous. The LSS for long-term missions are to use cycling-recycling systems, including system with biological recycling. In these systems, microbial populations as regenerative link should be useful and active agents. Some problems of microbial populations control and management are discussed in the paper.


Assuntos
Sistemas Ecológicos Fechados , Microbiologia Ambiental , Sistemas de Manutenção da Vida , Voo Espacial/instrumentação , Ausência de Peso , Medicina Aeroespacial , Biodegradação Ambiental , Reatores Biológicos , Chlorella , Resistência a Medicamentos , Humanos , Higiene , Sistema Imunitário/fisiologia , Gerenciamento de Resíduos/métodos
5.
Adv Space Res ; 35(9): 1507-11, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16173160

RESUMO

Using biotic turnover of substances in trophic chains, natural and artificial ecosystems are similar in functioning, but different in structure. It is necessary to have quantitative criteria to evaluate the efficiency of artificial ecosystems (AES). These criteria are dependent on the specific objectives for which the AES are designed. For example, if AES is considered for use in space, important criteria are efficiency in use of mass, power, volume (size) and human labor and reliability. Another task involves the determination of quantitative criteria for the functioning of natural ecosystems. To solve the problem, it is fruitful to use a hierarchical approach suitable for both individual links and the ecosystem as a whole. Energy flux criteria (principles) were developed to estimate the functional activities of biosystems at the population, community and ecosystem levels. A major feature of ecosystems as a whole is their biotic turnover of matter the rate of which is restricted by the lack of limiting substances. Obviously, the most generalized criterion is to take into account the energy flux used by the biosystem and the quantity of limiting substance included in its turnover. The use of energy flux by ecosystem, E(USED)--is determined from the photoassimilation of CO2 by plants (per time unit). It can be approximately estimated as the net primary production of photosynthesis (NPP). So, the ratio of CO2 photoassimilation rate (sometimes, measured as NPP) to the total mass of limiting substrate can serve as a main universal criterion (MUC). This MUC characterizes the specific cycling rate of limiting chemical elements in the system and effectiveness of every ecosystem including the global Biosphere. Comparative analysis and elaboration of quantitative criteria for estimation of natural and artificial ecosystems activities is of high importance both for theoretical considerations and for real applications.


Assuntos
Carbono/química , Sistemas Ecológicos Fechados , Ecossistema , Sistemas de Manutenção da Vida , Biomassa , Ecologia , Transferência de Energia , Fotossíntese , Dinâmica Populacional
6.
Adv Space Res ; 35(9): 1512-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16173161

RESUMO

Studying material transformations and biotic cycling in artificial ecosystems (AES), we need to know the principles of biological adaptation of active organisms to change in the environment. Microorganisms in AES for water purification are the most active transforming organisms and consumers of the organic substances contained in wastes. Utilization of organic substances is directly connected with the energy fluxes used by AES. According to energy criteria, the energy fluxes used by a biological system tend to reach maximum values under stable conditions. Unutilized substrate concentration decreases as a result of biological adaptations. After a dramatic change in environmental factors, for example, after a sharp increase in the flow rate of organic substances, the biological system is not able to react quickly. The concentration of unutilized substrate increases and the energy flux used by the biological system decreases. The structure of the microbial community also changes, with a decrease in biological diversity. The efficiency of energy use by simple terrestrial ecosystems depends on the energetic intensity and interactions between plants and rhizospheric microorganisms.


Assuntos
Sistemas Ecológicos Fechados , Ecossistema , Sistemas de Manutenção da Vida , Gerenciamento de Resíduos/métodos , Biodegradação Ambiental , Microbiologia Ambiental , Plantas/microbiologia , Esgotos/microbiologia , Microbiologia do Solo , Purificação da Água/métodos
7.
Adv Space Res ; 35(9): 1516-20, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16173162

RESUMO

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.


Assuntos
Ecossistema , Modelos Biológicos , Biodegradação Ambiental , Biomassa , Sistemas Ecológicos Fechados , Cadeia Alimentar , Sistemas de Manutenção da Vida
9.
Adv Space Res ; 31(7): 1731-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14552290

RESUMO

Simple models of terrestrial ecosystems with a limited number of components are an efficient tool to study the main laws of functioning of populations, including microbial ones, and their communities, as components of natural ecosystems, under variable environmental conditions. Among other factors are the increase of carbon dioxide in the atmosphere and limitation of plants' growth by biogenic elements. The main types of ecosystems' responses to changes in environmental conditions (a change in CO2 concentration) have been demonstrated in a "plants-rhizospheric microorganisms-artificial soil" simple experimental system. The mathematical model of interactions between plants and microorganisms under normal and elevated atmospheric CO2 and limitation by nutrients (nitrogen and phosphorus) yielded a qualitative agreement between calculated and experimental values of limiting substances concentrations and release rates of exudates.


Assuntos
Dióxido de Carbono/farmacologia , Ecossistema , Ambiente Controlado , Modelos Biológicos , Microbiologia do Solo , Triticum/efeitos dos fármacos , Atmosfera/química , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Relação Dose-Resposta a Droga , Nitrogênio/deficiência , Nitrogênio/metabolismo , Fósforo/deficiência , Fósforo/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Triticum/microbiologia
10.
Adv Space Res ; 31(7): 1667-74, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14503504

RESUMO

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 "top-down", "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.


Assuntos
Biomassa , Sistemas Ecológicos Fechados , Ecossistema , Cadeia Alimentar , Modelos Biológicos , Conservação dos Recursos Naturais , Ecologia/métodos , Ecologia/estatística & dados numéricos , Transferência de Energia , Plâncton , Dinâmica Populacional
11.
Adv Space Res ; 31(7): 1737-41, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14503511

RESUMO

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.


Assuntos
Canibalismo , Sistemas Ecológicos Fechados , Cadeia Alimentar , Modelos Biológicos , Fitoplâncton , Zooplâncton , Anfípodes , Animais , Aquicultura , Biomassa , Daphnia , Ecossistema
12.
Adv Space Res ; 31(7): 1763-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14503515

RESUMO

It has been demonstrated that the transgenic microorganism Escherichia coli Z905/pPHL7 (AprLux+) can exist for a long time at an elevated concentration of mineral salts. The microorganism was introduced into microcosms with sterile brackish water (salinity variable from 21 to 22 g l-1) taken from Lake Shira (Khakasia, Russia). The survival of the microorganism was estimated both by measuring the growth of the colonies on solid nutrient media and by the bioluminescence exhibited by the transgenic strain in samples from the microcosms and in the enrichment culture with the added selective factor-ampicillin (50 micrograms/ml). In the enrichment culture, the bioluminescent signal was registered through the 160-day experiment. It has been shown that in the closed microcosms with brackish water the E. coli strain becomes heterogeneous in its ampicillin resistance. The populations of the transgenic strain were mainly represented by isolates able to persist in the medium containing 50 micrograms/ml, but there were also the cells (about 10%) with the threshold of ampicillin resistance not more than 0.05 micrograms/ml. Thus, it was shown that in the microcosms with brackish water and in the absence of the selective factor the transgenic strain survives and retails the recombinant plasmid.


Assuntos
Sistemas Ecológicos Fechados , Escherichia coli/crescimento & desenvolvimento , Minerais , Organismos Geneticamente Modificados/crescimento & desenvolvimento , Sais , Microbiologia da Água , Ampicilina/farmacologia , Resistência a Ampicilina , Cloretos , Contagem de Colônia Microbiana , Meios de Cultura , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Medições Luminescentes , Magnésio , Organismos Geneticamente Modificados/genética , Plasmídeos/genética , Potássio , Federação Russa , Sódio , Sulfatos
13.
Adv Space Res ; 31(7): 1769-74, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14503516

RESUMO

The processes resulting from the introduction of the tranagenic microorganism (TM) E. coli Z905/pPHL7 into aquatic microcosms have been modeled experimentally. It has been shown that the TM E. coli is able to adapt to a long co-existence with indigenous heterotrophic microflora in variously structured microcosms. In more complex microcosms the numerical dynamics of the introduced E. coli Z905/pPHL7 population is more stable. In the TM populations staying in the microcosms for a prolonged time, changes are recorded in the phenotypic expression of plasmid genes (ampicillin resistance and the luminescence level) and chromosome genes (morphological and physiological traits). However, in our study microcosms, the recombinant plasmid persisted in the TM cells for 6 years after the introduction, and as the population adapts to the conditions of the microcosms, the efficiency of the cloned gene expression in the cells is restored. In the microcosms with high microalgal counts (10(7) cells/ml), cells with a high threshold of sensitivity to ampicillin dominate in the population of the TM E. coli Z905/pPHL7.


Assuntos
Monitoramento Ambiental , Escherichia coli/crescimento & desenvolvimento , Água Doce/microbiologia , Regulação Bacteriana da Expressão Gênica , Organismos Geneticamente Modificados/crescimento & desenvolvimento , Microbiologia da Água , Adaptação Fisiológica , Resistência a Ampicilina , Animais , Contagem de Colônia Microbiana , Daphnia/crescimento & desenvolvimento , Sistemas Ecológicos Fechados , Escherichia coli/genética , Eucariotos , Medições Luminescentes , Plasmídeos/genética , Fatores de Tempo
14.
Biofizika ; 47(5): 920-5, 2002.
Artigo em Russo | MEDLINE | ID: mdl-12397967

RESUMO

A mathematical model describing the interaction of plants and rhizospheric microorganisms on complete mineral medium at a higher CO2 level in the atmosphere was constructed. The positive effect of CO2-enrichment on the system plant--rhizospheric microorganisms was shown. The effect of rhizospheric microorganisms on plant growth at normal and high level of carbon dioxide was demonstrated. It was shown that the biomass of plant in the system is smaller than the biomass of plant growing without microorganisms. It was experimentally demonstrated that a simple ecosystem wheat--Pseudomonas putida--artificial soil develops and functions differently than its individual constituents in the case of a wheat-artificial soil system. With unlimited nutrition and a higher CO2 level (0.06%), plants with roots inoculated with microorganisms have a smaller biomass than plants that were not inoculated with microorganisms.


Assuntos
Dióxido de Carbono/fisiologia , Pseudomonas putida/fisiologia , Triticum/fisiologia , Algoritmos , Biomassa , Ecossistema , Modelos Biológicos , Sementes , Triticum/microbiologia
15.
Adv Space Res ; 27(9): 1497-504, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11695428

RESUMO

Closed Artificial ecosystems (CAES) have good prospects for wide use as new means for quantitative studies of different types of both natural ecosystems and man-made ones. The paper deals with the discussion of three points of CAES applications. The first one is of importance for theoretical ecology development and is connected with bringing together "holistic" and "merological" approaches in ecosystems studies. Using CAES, we can combine both approaches, taking into account the biotic turnover of limiting substrates which few in number even for complicated natural ecosystems. The second CAES use concerns the development of "ecosystems health" concept and application of a key-factor-approach for the indication and measurement of healthy unhealthy state and functioning of ecosystems or their links. The third use is more of an applied nature, oriented to the intensification of bioremediation or biodepollution processes in different types of ecosystems, including the global biosphere. Grant numbers: N 99-04-96017, N25.


Assuntos
Sistemas Ecológicos Fechados , Ecossistema , Transferência de Energia , Sistemas de Manutenção da Vida , Dinâmica Populacional , Biodegradação Ambiental , Planeta Terra , Ecologia , Microbiologia Ambiental , Leveduras
16.
Adv Space Res ; 27(9): 1571-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11695438

RESUMO

The role of key environmental factors in adaptation of spore-forming and non-spore-forming transgenic microorganisms (TM) have been studied in model ecosystems. Model TM Escherichia coli Z905 (bearing plasmid genes of bacterial luminescence Ap (r) Lux+) has been found to have a higher adaptation potential than TM Bacillus subtilis 2335/105 (bearing genes of human alpha 2-interferon Km (r) Inf+), planned for employment as a living vaccine under varying environmental conditions. Effects of abiotic factors on migration of natural and recombinant plasmids between microorganisms under model ecosystem conditions has been estimated. The transgenic microorganisms with low copy number survived better under introduction conditions in the microcosms studied. This trend has been shown to be independent of the microcosm type and its complexity. Grant numbers: 99-04-96017, 25, 00-07-9011.


Assuntos
Adaptação Fisiológica , Ecossistema , Organismos Geneticamente Modificados/crescimento & desenvolvimento , Dinâmica Populacional , Microbiologia da Água , Bacillus subtilis , Contenção de Riscos Biológicos , Escherichia coli , Água Doce/microbiologia , Expressão Gênica , Micrococcus , Organismos Geneticamente Modificados/genética , Pressão Osmótica , Plasmídeos , Medição de Risco
17.
Adv Space Res ; 27(9): 1563-70, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11695437

RESUMO

Functional, regulatory and indicator features of microorganisms in development and functioning of the systems and sustaining stability of three man-made ecosystem types has been studied. 1) The functional (metabolic) feature was studied in aquatic ecosystems of biological treatment of sewage waters for the reducer component. 2) The regulatory feature of bacteria for plants (producer component) was studied in simple terrestrial systems "wheat plants-rhizospheric microorganisms-artificial soil" where the behavior of the system varied with activity of the microbial component. For example with atmospheric carbon dioxide content elevated microbes promote intensification of photosynthesis processes, without binding the carbon in the plant biomass. 3) The indicator feature for the humans (consumer component) was studied in Life Support Systems (LSS). High sensitivity of human microflora to system conditions allowed its use as an indicator of the state of both system components and the entire ecosystem. Grant numbers: N99-04-96017, N15.


Assuntos
Carbono/metabolismo , Sistemas Ecológicos Fechados , Microbiologia Ambiental , Raízes de Plantas/microbiologia , Eliminação de Resíduos Líquidos , Biomassa , Reatores Biológicos , Dióxido de Carbono/metabolismo , Ecossistema , Humanos , Intestinos/microbiologia , Sistemas de Manutenção da Vida , Raízes de Plantas/metabolismo , Esgotos , Triticum/metabolismo , Triticum/microbiologia
18.
Adv Space Res ; 27(9): 1587-92, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11695440

RESUMO

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. Grant numbers: 99-04-96017/2000.


Assuntos
Evolução Biológica , Simulação por Computador , Sistemas Ecológicos Fechados , Ecossistema , Cadeia Alimentar , Animais , Daphnia , Metabolismo Energético , Eucariotos , Modelos Biológicos , Plâncton , Poecilia
19.
Adv Space Res ; 27(9): 1593-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11695441

RESUMO

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. Grant numbers: N99-04-96017, N25.


Assuntos
Ecossistema , Cadeia Alimentar , Modelos Biológicos , Animais , Biomassa , Sistemas Ecológicos Fechados , Escherichia coli , Eucariotos , Água Doce
20.
Adv Space Res ; 27(9): 1599-603, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11695442

RESUMO

The work analyzes functioning of a "producer-consumer" closed aquatic system with spatially separated links, where each component consisted of two species. Producers in the system were the microalgae of Chlorella vulgaris and Scenedesmus sp., consumers--Paramecium caudatum infusoria and Brachionus sp. rotifers. In the experiment the competing predators were consuming on a mixed culture of algae, and the competition of algae was studied under nitrogen limitation. Under these conditions competitiveness of Scenedesmus was higher than that of Chlorella vulgaris. Metabolism products of Scenedesmus algae have been found to have negative effect on reproduction of Paramecium caudatum protozoa. Predator population dynamics in the "consumer" link demonstrated that the rotifers that consume two algal species are more competitive compared to protozoa feeding on chlorella only. Grant numbers: N99-04-96017, N25.


Assuntos
Sistemas Ecológicos Fechados , Cadeia Alimentar , Água Doce , Nitrogênio/metabolismo , Animais , Chlorella , Clorófitas , Paramecium , Rotíferos
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