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Using multispectral sensor WASP-LITE to analyze harmful algal blooms /McNamara, Shari J. January 2007 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (leaves 133-138).
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Remote Sensing of Cyanobacteria in Case II Waters Using Optically Active Pigments, Chlorophyll a and PhycocyaninRandolph, Kaylan Lee 27 March 2007 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Nuisance blue-green algal blooms contribute to aesthetic degradation of water resources and produce toxins that can have serious adverse human health effects. Current field-based methods for detecting blooms are costly and time consuming, delaying management decisions. Remote sensing techniques which utilize the optical properties of blue-green algal pigments (chlorophyll a and phycocyanin) can provide rapid detection of blue-green algal distribution. Coupled with physical and chemical data from lakes, remote sensing can provide an efficient method for tracking cyanobacteria bloom occurrence and toxin production potential to inform long-term management strategies. In-situ field reflectance spectra were collected at 54 sampling sites on two turbid, productive Indianapolis reservoirs using ASD Fieldspec (UV/VNIR) spectroradiometers. Groundtruth samples were analyzed for in-vitro pigment concentrations and other physical and chemical water quality parameters. Empirical algorithms by Gitelson et al. (1986, 1994), Mittenzwey et al. (1991), Dekker (1993), and Schalles et al. (1998), were applied using a combined dataset divided into a calibration and validation set. Modified semi-empirical algorithms by Simis et al. (2005) were applied to all field spectra to predict phycocyanin concentrations. Algorithm accuracy was tested through a least-squares regression and residual analysis. Results show that for prediction of chlorophyll a concentrations within the range of 18 to 170 ppb, empirical algorithms yielded coefficients of determination as high as 0.71, RMSE 17.59 ppb, for an aggregated dataset (n=54, p<0.0001). The Schalles et al. (2000) empirical algorithm for estimation of phycocyanin concentrations within the range of 2 to 160 ppb resulted in an r2 value of 0.70, RMSE 23.97 ppb (n=48, p<0.0001). The Simis et al. (2005) semi-empirical algorithm for estimation of chlorophyll a and phycocyanin concentrations yielded coefficients of determination of 0.69, RMSE 20.51 ppb (n=54, p<0.0001) and 0.85, RMSE 24.61 pbb (n=49, p<0.0001), respectively. Results suggest the Simis et al. (2005) algorithm is robust, where error is highest in water with phycocyanin concentrations of less than 10 ppb and in water where chlorophyll a dominates (Chl:PC>2). A strong correlation between measured phycocyanin concentrations and blue-green algal biovolume measurements was also observed (r2=0.95, p<0.0001).
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The role of nitrogen in the regulation of microcystin content in Microcystis aeruginosaDowning, T. G. 12 1900 (has links)
Thesis (PhD)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: Several genera of cyanobacteria produce a range of toxins. The increased
rate of eutrophication of surface fresh waters due to anthropogenic inputs has
resulted in more frequent and severe cyanobacterial bloom events. Such
bloom events make impoundments unsuitable for recreational use and
increase the cost of production of potable water due to the necessity for
removal of toxins released from cells during the purification process.
Microcystis aeruginosa is the major freshwater bloom-forming toxic
cyanobacterium. Concentrations of the hepatotoxin, microcystin, are highly
variable in blooms. Published literature on environmental conditions leading to
increased microcystin production was often contradictory and in many cases
did not consider all relevant parameters. However, environmental nitrogen
and phosphorus, temperature and light, and growth rate were implicated in
regulation of toxin content. The purpose of this work was therefore to
investigate environmental factors (specifically nitrogen and phosphorus) and
cellular activities (specifically carbon fixation and nitrogen uptake rates and
growth rate) involved in the modulation of microcystin production in M.
aeruginosa in order to clarify the role of these parameters, and in an attempt
to identify regulatory mechanisms for microcystin production. Environmental
nitrogen, phosphorus and growth rate were shown to co-modulate microcystin
production in M. aeruginosa. Adequate phosphorus is required for
photosynthetic carbon fixation. Phosphorus uptake by M. aeruginosa is
strongly correlated with carbon fixation rate. Although microcystin content
increased with increasing nitrogen:phosphorus ratios in culture medium,
under phosphorus limitation microcystin content was lower irrespective of
nitrogen concentrations. This observation and the requirements for fixed
carbon for nitrogen assimilation therefore prompted investigation of the effects
of cellular carbon fixation and nitrogen uptake in the modulation of microcystin
production. Microcystin production was found to be enhanced when nitrogen
uptake rate relative to carbon fixation rate was higher than that required for
balanced growth. The cellular nitrogen:carbon ratio above which microcystin
concentrations increased substantially, corresponded to the Redfield ratio for balanced growth. Investigation of potential regulatory mechanisms involving
the cyanobacterial nitrogen regulator, NtcA, yielded putative NtcA binding
sites indicative of repression in the microcystin synthetase gene cluster. In
culture, the polypeptide synthetase module gene, mcyA, and ntcA were
inversely expressed as a function of carbon-fixation:nitrogen-uptake potential.
However, no increase or decrease in microcystin production could be linked to
either glutamine, glutamate or a-ketoglutarate, metabolites that are involved in
regulation of ntcA. The role of NtcA in regulation of microcystin production
could therefore not be confirmed. In conclusion, these data suggest that
microcystin production is metabolically regulated by cellular C:N balance and
specific growth rate. The primary importance of nitrogen and carbon was
demonstrated by a simple model where only nitrogen uptake, carbon fixation
and growth rate were used to predict microcystin levels. The model also
explains results previously described in literature. Similarly, an artificial neural
network model was used to show that the carbon fixation dependence on
phosphorus allows accurate prediction of microcystin levels based on growth
rate and environmental nitrogen and phosphorus. / AFRIKAANSE OPSOMMING: Verskeie genera van sianobakterieë produseer 'n verskeidenheid van
toksiene. Die toename in die tempo van eutrofikasie van varswater
oppervlaktes as gevolg van antropogeniese insette veroorsaak al hoe meer
en al hoe erger sianobakteriële infestasies. Dit veroorsaak probleme vir
ontspanninggebruik van hierdie waters en verhoog die koste van produksie
van drinkbare water as gevolg van die noodsaak om die toksiene wat deur die
selle gedurende die suiweringsproses vrygelaat word te verwyder. Microcystis
aeruginosa is die belangrikste varswater bloeisel-vormende toksiese
sianobakterium. Die konsentrasie van die hepatotoksien mikrosistien is hoogs
varieerbaar in sulke bloeisels. Gepubliseerde literatuur oor die
omgewingskondisies wat lei na verhoogde mikrosistienproduksie is dikwels
weersprekend en neem in vele gevalle nie al die relevante parameters in ag
nie. Desnieteenstaande word omgewingstikstof, fosfor, temperatuur en lig,
asook groeisnelheid, geïmpliseer in die regulering van toksieninhoud. Die doel
van hierdie navorsing was dus om omgewingsfaktore (spesifiek stikstof en
fosfor) en sellulêre aktiwiteite (spesifiek koolstoffiskering en die snelheid van
stikstofopname en van groei) betrokke by die modulering van
mikrosistienproduksie in M. aeruginosa te ondersoek in 'n poging om die rol
van hierdie parameters te verstaan en om regulatoriese meganismes vir
mikrosistienproduksie te identifiseer. In hierdie studie is aangetoon dat
omgewingstikstof en fosfor sowel as groeisnelheid mikrosistienproduksie in M.
aeruginosa ko-moduleer. Genoegsame fosfor word benodig vir fotosintetiese
koolstoffiksering. Fosforopname deur M. aeruginosa korreleer sterk met die
snelheid van koolstoffiksering. Alhoewel mikrosistieninhoud toegeneem het
met 'n toename in die stikstof:fosfor verhouding in die kultuurmedium, was die
mikrosistieninhoud onder kondisies van fosforlimitering laer ongeag die
stikstofkonsentrasie. Hierdie waarneming, tesame met die noodsaak van
gefikseerde koolstof vir stikstofassimilering, het gelei na 'n studie van die
effekte van sellulêre koolstoffiksering and stikstofopname op die modulering
van mikrosistienproduksie. Dit is gevind dat mikrosistienproduksie verhoog
was wanneer die snelheid van stikstofopname relatief tot die snelheid van koolstoffiksering hoër was as die waarde wat benodig word vir gebalanseerde
groei. Die sellulêre stikstof:koolstof verhouding waarbo
mikrosistienkonsentrasies beduidend verhoog is stem ooreen met die
Redfield verhouding vir gebalanseerde groei. 'n Ondersoek na potensiële
reguleringsmeganismes waarby die sianobakteriële stikstofreguleerder NtcA
betrokke is het gelei na die ontdekking van moontlike NtcA bindingseteis; dit
kan dui op die repressie van die mikrosistiensintetase geengroepering. Onder
kultuurkondisies is gevind dat die geen vir die polipeptiedsintetase module,
mcyA, en ntcA omgekeerd uitgedruk word as 'n funksie van
koolstofopname:stikstofopname potensiale. Geen toename of afname in
mikrosistienproduksie kon egter gekoppel word aan óf glutamien, óf
glutamaat, óf a-ketoglutaraat nie, metaboliete wat betrokke is by die
regulering van ntcA. Die rol van NtcA in die regulering van
mikrosistienproduksie kon dus nie bevestig word nie. Die gevolgtrekking is
dus gemaak dat mikrosistienproduksie metabolies gereguleer word deur die
C:N balans en die spesifieke groeisnelheid. Die primêre belang van stikstof en
koolstof is gedemonstreer deur 'n eenvoudige model waarin slegs
stikstofopname, koolstoffiksering en groeisnelheid gebruik word om
mikrosistienvlakke te voorspel. Die model verklaar ook resultate wat tevore in
die literatuur beskryf is. Soortgelyk is 'n artifisiële neurale netwerkmodel
gebruik om te toon dat die afhanklikheid van koolstoffiksering van fosfor
akkurate voorspelling van mikrosistienvlakke gebaseer of groeisnelheid en
omgewingstikstof en fosfor moontlik maak.
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Estudo da comunidade fitoplanctônica como bioindicador de poluição em três reservatórios em série do Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SP / Phytoplankton communitys study as bioindicator of pollution in three cascading reservoir system in Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SPLopes, Adriana Guidetti Dias 13 August 2007 (has links)
Os três reservatórios rasos e em série localizam-se no Parque Estadual das Fontes do Ipiranga (PEFI), região sudoeste do município de São Paulo, numa unidade de conservação que abriga as nascentes do histórico riacho do Ipiranga. O primeiro reservatório recebe água do Lago das Garças, um sistema artificial eutrófico, onde já foram detectadas florações de cianobactérias potencialmente tóxicas e com problemas ecológicos, sanitários e estéticos. Objetivo. Analisar a variação sazonal da comunidade fitoplanctônica de três reservatórios rasos subseqüentes a um lago hipereutrófico localizado no município de São Paulo/SP, visando avaliar a qualidade da água durante o sistema em série. Material e Métodos. As coletas foram realizadas trimensalmente durante o período de um ano (outubro/2005 a julho/2006), em uma estação de amostragem em cada um dos três reservatórios e a duas profundidades: superfície e fundo. Foram determinadas variáveis morfométricas (área superficial, perímetro, comprimento máximo e profundidade), climatológicas (temperatura do ar e precipitação), físicas e químicas (temperatura da água, transparência, zona eufótica, pH, condutividade, turbidez, oxigênio dissolvido, demanda bioquímica de oxigênio, fósforo total e ortofosfato, nitrogênio total e amoniacal), biológicas (coliformes totais e termotolerantes, clorofila-a, feofitina, composição florística, densidade total, biovolume, estimativa do número de células e espécies descritoras) e aplicações de índices biológicos. Na análise qualitativa foi empregada a rede de malha de 20 µm e identificação em microscópio óptico binocular com câmara clara. Na análise quantitativa, foi utilizado a garrafa coletora e método de sedimentação em câmara de volume definido e contagem em microscópio invertido. A ordenação dos dados foi realizada por meio da análise de componentes principais (ACP) e análise de correspondência canônica (ACC). Resultados. Como conseqüência da floração de cianobactérias registradas nos três reservatórios, foram identificados 125 táxons distribuídos em 12 classes. A classe com maior representatividade foi Chlorophyceae com 38,8%, seguida por Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) e 11,1% para as demais classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae e Fragilariophyceae). Os táxons que apresentaram 100% de freqüência foram: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). As espécies descritoras que podem ser consideradas como bioindicadoras de poluição foram Cylindrospermopsis raciborskii e Chroococcus minutus, que juntas contribuíram com 79,4% de toda densidade deste estudo. Conclusões. A comunidade fitoplanctônica respondeu sazonalmente às estações do ano, predominando a classe Cyanophyceae na primavera e a classe Chlorophyceae nas demais estações e não houve melhoria na qualidade da água durante a série. / The three shallow cascading reservoir system are located in Parque Estadual das Fontes do Ipiranga (PEFI) Biological Reserve in the southern of São Paulo city where located headwater Ipiranga Stream. The first reservoir is linked to Lago das Garças, a shallow and eutrophic environment, where have become frequent blooms of Cyanobacteria that produce aggressive toxins which cause problems to environment and public health. Objective. This study aimed to analyze the sazonal variation of the phytoplankton community of three shallow cascading reservoir system subsequent of a eutrophic lake and avaliated the water quality. Material and Methods. Samples were collected quarterly during the period of one year (October/2005 to July/2006), in the deepest part of the each lake, in two depths. Morphometric variables (superficial area, perimeter, maximum length and depth), climatic variables (air temperature and precipitation), physical and chemical variables (water temperature, transparence of water, euphotic zone, pH, conductivity, turbidity, dissolved oxygen, biochemical oxygen demand, nutrients), biological variables (total and fecal coliforms, chlorophyll-a, pheopigments, species composition, density, biovolume, cells number and descriptions species) were determined. Qualitative samples were collected at the surface using planktonic net (20 µm) and identificated using a binocular optic microscope. Quantitative samples were obtained by collecting bottle and counting in inverted microscope. Multivariate statistical analysis was applied to calculate the correlations between biological and environmental data. Results. The phytoplankton community was composed of 125 taxons distributed in 12 classes: Chlorophyceae (38,8%) was the main class regarding species richness and density, followed by the Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) and 11,1% for others classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae and Fragilariophyceae). Taxons that had appeared during all study are: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). Cylindrospermopsis raciborskii and Chroococcus minutus are descriptions species and they can be considered bioindicator of pollution because their density are elevated (79,4% of total density). Conclusions. The phytoplankton community as well as the environmental variables responded to the seasonality, predominance of Cyanophyceae in spring and Chlorophyceae in others stations. It didnt have improvement in the quality of the water during the serie.
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Estudo da comunidade fitoplanctônica como bioindicador de poluição em três reservatórios em série do Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SP / Phytoplankton communitys study as bioindicator of pollution in three cascading reservoir system in Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SPAdriana Guidetti Dias Lopes 13 August 2007 (has links)
Os três reservatórios rasos e em série localizam-se no Parque Estadual das Fontes do Ipiranga (PEFI), região sudoeste do município de São Paulo, numa unidade de conservação que abriga as nascentes do histórico riacho do Ipiranga. O primeiro reservatório recebe água do Lago das Garças, um sistema artificial eutrófico, onde já foram detectadas florações de cianobactérias potencialmente tóxicas e com problemas ecológicos, sanitários e estéticos. Objetivo. Analisar a variação sazonal da comunidade fitoplanctônica de três reservatórios rasos subseqüentes a um lago hipereutrófico localizado no município de São Paulo/SP, visando avaliar a qualidade da água durante o sistema em série. Material e Métodos. As coletas foram realizadas trimensalmente durante o período de um ano (outubro/2005 a julho/2006), em uma estação de amostragem em cada um dos três reservatórios e a duas profundidades: superfície e fundo. Foram determinadas variáveis morfométricas (área superficial, perímetro, comprimento máximo e profundidade), climatológicas (temperatura do ar e precipitação), físicas e químicas (temperatura da água, transparência, zona eufótica, pH, condutividade, turbidez, oxigênio dissolvido, demanda bioquímica de oxigênio, fósforo total e ortofosfato, nitrogênio total e amoniacal), biológicas (coliformes totais e termotolerantes, clorofila-a, feofitina, composição florística, densidade total, biovolume, estimativa do número de células e espécies descritoras) e aplicações de índices biológicos. Na análise qualitativa foi empregada a rede de malha de 20 µm e identificação em microscópio óptico binocular com câmara clara. Na análise quantitativa, foi utilizado a garrafa coletora e método de sedimentação em câmara de volume definido e contagem em microscópio invertido. A ordenação dos dados foi realizada por meio da análise de componentes principais (ACP) e análise de correspondência canônica (ACC). Resultados. Como conseqüência da floração de cianobactérias registradas nos três reservatórios, foram identificados 125 táxons distribuídos em 12 classes. A classe com maior representatividade foi Chlorophyceae com 38,8%, seguida por Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) e 11,1% para as demais classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae e Fragilariophyceae). Os táxons que apresentaram 100% de freqüência foram: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). As espécies descritoras que podem ser consideradas como bioindicadoras de poluição foram Cylindrospermopsis raciborskii e Chroococcus minutus, que juntas contribuíram com 79,4% de toda densidade deste estudo. Conclusões. A comunidade fitoplanctônica respondeu sazonalmente às estações do ano, predominando a classe Cyanophyceae na primavera e a classe Chlorophyceae nas demais estações e não houve melhoria na qualidade da água durante a série. / The three shallow cascading reservoir system are located in Parque Estadual das Fontes do Ipiranga (PEFI) Biological Reserve in the southern of São Paulo city where located headwater Ipiranga Stream. The first reservoir is linked to Lago das Garças, a shallow and eutrophic environment, where have become frequent blooms of Cyanobacteria that produce aggressive toxins which cause problems to environment and public health. Objective. This study aimed to analyze the sazonal variation of the phytoplankton community of three shallow cascading reservoir system subsequent of a eutrophic lake and avaliated the water quality. Material and Methods. Samples were collected quarterly during the period of one year (October/2005 to July/2006), in the deepest part of the each lake, in two depths. Morphometric variables (superficial area, perimeter, maximum length and depth), climatic variables (air temperature and precipitation), physical and chemical variables (water temperature, transparence of water, euphotic zone, pH, conductivity, turbidity, dissolved oxygen, biochemical oxygen demand, nutrients), biological variables (total and fecal coliforms, chlorophyll-a, pheopigments, species composition, density, biovolume, cells number and descriptions species) were determined. Qualitative samples were collected at the surface using planktonic net (20 µm) and identificated using a binocular optic microscope. Quantitative samples were obtained by collecting bottle and counting in inverted microscope. Multivariate statistical analysis was applied to calculate the correlations between biological and environmental data. Results. The phytoplankton community was composed of 125 taxons distributed in 12 classes: Chlorophyceae (38,8%) was the main class regarding species richness and density, followed by the Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) and 11,1% for others classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae and Fragilariophyceae). Taxons that had appeared during all study are: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). Cylindrospermopsis raciborskii and Chroococcus minutus are descriptions species and they can be considered bioindicator of pollution because their density are elevated (79,4% of total density). Conclusions. The phytoplankton community as well as the environmental variables responded to the seasonality, predominance of Cyanophyceae in spring and Chlorophyceae in others stations. It didnt have improvement in the quality of the water during the serie.
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Using Wetlands to Prevent the Surface Accumulation of <i>Aphanizomenon flos-aquae</i> from Upper Klamath LakeRouhe, Arick Christopher 02 August 2018 (has links)
The ability to regulate buoyancy (sinking and floating) using cellular gas vesicles is a unique characteristic that allows many common bloom-forming cyanobacteria to accumulate at water surfaces and dominate systems. Typical control and management strategies include nutrient manipulation and phosphorus reduction, which are effective but do not reduce the advantage of buoyancy control. Since buoyancy control is based upon a mechanism that is driven by photosynthesis along with environmental conditions that trigger vesicle formation and ion exchange, buoyancy regulation can be influenced by manipulating extracellular conditions. In this study I manipulated extracellular conditions using wetland water and additions of potassium, sodium, and calcium in small-scale lab experiments and larger scale, near-lake containers with Aphanizomenon flos-aquae from Upper Klamath Lake, Oregon. The results indicate a target mixture of 10% wetland water reduces surface accumulation, increases cellular turgor pressure (a measure of the ability of gas vesicle forming cells to control buoyancy), and leads to fewer rafts at the surface of the water column. By adding ions at the same concentration as the target wetland mixture, similar results were found. This research represents the basis of a possible strategy for mitigating surface blooms of buoyant cyanobacteria in lakes using wetland water and/or ion additions that could be used in tandem with nutrient manipulation and phosphorus reduction.
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Ecological studies of phytoplankton and harmful algal blooms in Junk Bay, Hong Kong /Lu, Songhui. January 2001 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 201-227).
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Use of artificial neural networks for modelling multivariate water quality times series / by Holger Robert Maier.Maier, Holger R. January 1995 (has links)
Corrigenda attached to back end paper. / Bibliography: p. 526-559. / xxx, 559 p. : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This research analyses the suitability of back-propagation artifical neural networks (ANNs) for modelling multivariate water quality time series. The ANNs are successfully applied to two case studies, the long-term forcasting of salinity and the modelling of blue-green algae, in the River Murray, Australia. / Thesis (Ph.D.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 1996?
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Phytoplankton-zooplankton interactions in Mt. Bold Reservoir, South Australia /Merrick, Chester John. January 1990 (has links) (PDF)
Thesis (Ph. D.)--Dept. of Botany, University of Adelaide, 1991. / Typescript (Photocopy). Includes bibliographical references (leaves 166-189).
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Investigations of the influence of physical factors on some marine ecological systems /Öberg, Jörgen. January 2005 (has links)
Thesis (Ph. D.)--Göteborg University, 2005. / Includes bibliographical references.
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