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Salomon, Paulo
Publications (10 of 28) Show all publications
Lindh, M. V., Riemann, L., Baltar, F., Romero-Oliva, C., Salomon, P., Granéli, E. & Pinhassi, J. (2013). Consequences of increased temperature and acidification on bacterioplankton community composition during a mesocosm spring bloom in the Baltic Sea. Environmental Microbiology Reports, 5(2), 252-262
Open this publication in new window or tab >>Consequences of increased temperature and acidification on bacterioplankton community composition during a mesocosm spring bloom in the Baltic Sea
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2013 (English)In: Environmental Microbiology Reports, ISSN 1758-2229, E-ISSN 1758-2229, Vol. 5, no 2, p. 252-262Article in journal (Refereed) Published
Abstract [en]

Despite the paramount importance of bacteria for biogeochemical cycling of carbon and nutrients, little is known about the potential effects of climate change on these key organisms. The consequences of the projected climate change on bacterioplankton community dynamics were investigated in a Baltic Sea spring phytoplankton bloom mesocosm experiment by increasing temperature with 3°C and decreasing pH by approximately 0.4 units via CO2 addition in a factorial design. Temperature was the major driver of differences in community composition during the experiment, as shown by denaturing gradient gel electrophoresis (DGGE) of amplified 16S rRNA gene fragments. Several bacterial phylotypes belonging to Betaproteobacteria were predominant at 3°C but were replaced by members of the Bacteriodetes in the 6°C mesocosms. Acidification alone had a limited impact on phylogenetic composition, but when combined with increased temperature, resulted in the proliferation of specific microbial phylotypes. Our results suggest that although temperature is an important driver in structuring bacterioplankton composition, evaluation of the combined effects of temperature and acidification is necessary to fully understand consequences of climate change for marine bacterioplankton, their implications for future spring bloom dynamics, and their role in ecosystem functioning.

National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-22627 (URN)10.1111/1758-2229.12009 (DOI)000315851200008 ()23584969 (PubMedID)2-s2.0-84874716930 (Scopus ID)
Available from: 2012-11-27 Created: 2012-11-27 Last updated: 2019-01-23Bibliographically approved
Pérez Blanco, E., Hagström, J., Salomon, P. & Granéli, E. (2013). Detection of Heterosigma akashiwo (Hada) using specific RNA probes: Variability of RNA content with environmental conditions. Harmful Algae, 24, 80-88
Open this publication in new window or tab >>Detection of Heterosigma akashiwo (Hada) using specific RNA probes: Variability of RNA content with environmental conditions
2013 (English)In: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 24, p. 80-88Article in journal (Refereed) Published
Abstract [en]

The raphidophyte Heterosigma akashiwo, which forms toxic blooms, causes major economical losses to the fish industry because of the fish kills involved. It is therefore important to be able to detect not only H. akashiwo but other toxic phytoplankton species as well, rapidly and accurately to reduce losses by fish kills. With this purpose, DNA sequences from H. akashiwo 18S and 28S rRNA gene regions were studied in silico to design species-specific probes to be used in a microarray format. Three strains of H. akashiwo (AC 265, AC 266 and GUMACC 120) were grown at optimal conditions and transferred into new environmental conditions changing either the light intensity, salinity, temperature or nutrient concentrations, to check if any of these environmental conditions induced changes in the cellular RNA concentration. The aim of this experiment was the calibration of several species-specific probes for the quantification of H. akashiwo. Differences on RNA content were not significant (p < 0.05) in any of the treatments, therefore the calibration curves were validated. The designed probes are reliable for the detection and quantification of H. akashiwo cells in natural waters. (C) 2013 Elsevier B.V. All rights reserved.

Keywords
Calibration, Environmental conditions, Heterosigma, Microarray, RNA probes
National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-26299 (URN)10.1016/j.hal.2013.02.001 (DOI)000317327100008 ()2-s2.0-84874970188 (Scopus ID)
Available from: 2013-06-11 Created: 2013-06-11 Last updated: 2017-12-06Bibliographically approved
Laohaprapanon, S., Kaczala, F., Salomon, P., Marques, M. & Hogland, W. (2012). Toxicity on the Microalgae Desmodesmus subspicatus: Wastewater Generated during washing procedures in a Wood-floor industry. In: : . Paper presented at ECOTOX XII Congrasso Brasileiro De Ecotoxicologia.
Open this publication in new window or tab >>Toxicity on the Microalgae Desmodesmus subspicatus: Wastewater Generated during washing procedures in a Wood-floor industry
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2012 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Environmental Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-25296 (URN)
External cooperation:
Conference
ECOTOX XII Congrasso Brasileiro De Ecotoxicologia
Available from: 2013-04-11 Created: 2013-04-11 Last updated: 2016-11-17Bibliographically approved
Laohaprapanon, S., Kaczala, F., Salomon, P., Marques, M. & Hogland, W. (2012). Wastewater generated during cleaning/washing procedures in a wood-floor industry: toxicity on the microalgae Desmodesmus subspicatus. Environmental technology, 33(21), 2439-2446
Open this publication in new window or tab >>Wastewater generated during cleaning/washing procedures in a wood-floor industry: toxicity on the microalgae Desmodesmus subspicatus
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2012 (English)In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 33, no 21, p. 2439-2446Article in journal (Refereed) Published
Abstract [en]

In industries based on dry processes, such as wood floor and wood furniture manufacture, wastewater is mainly generated after cleaning of surfaces, storage tanks and machinery. Owing to the small volumes, onsite treatment options and potential environmental risks posed to aquatic ecosystems due to discharge of these wastewaters are seldom investigated. In the present study, the effects of cleaning wastewater streams generated at two wood floor production lines on Desmodesmus subspicatus were investigated. The microalgae was exposed to different wastewater concentrations (100, 50, 25, 12.5 and 6.25% v:v) and the algae growth evaluation was based on in vivo chlorophyll fluorescence, cell density, cell size (number of cells/colony) and cell ratio (length/width). Inhibitory effects of the tested wastewaters on the microalgae were positively related to concentration and negatively related to exposure time. The EC50,24 h of blade cleaning wastewater (BCW) and floor cleaning wastewater (FCW) were 3.36 and 5.87% (v:v), respectively. No negative effect on cell colony formation was caused by BCW, whereas an increase of 90% unicellular cells was observed in FCW concentrations below 50% (v:v). At the lowest concentration (3.13% v:v) where no growth inhibition was observed, both wastewater streams caused changes in cell dimensions by increasing cell length and width. To conclude, wastewaters generated during cleaning procedures in the wood floor industries can have severe environmental impacts on aquatic organisms, even after high dilution. Therefore, these wastewaters must be treated before being discharged into water bodies.

Keywords
growth inhibition, Desmodesmus subspicatus, colony sizes, induced unicellular cell, wood industry
National Category
Environmental Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-23106 (URN)10.1080/09593330.2012.671853 (DOI)000311120000009 ()2-s2.0-84871073383 (Scopus ID)
External cooperation:
Available from: 2012-12-20 Created: 2012-12-20 Last updated: 2017-12-06Bibliographically approved
Minnhagen, S., Kim, M., Salomon, P., Yih, W., Granéli, E. & Park, M. G. (2011). Active uptake of kleptoplastids by Dinophysis caudata from its ciliate prey Myrionecta rubra. Aquatic Microbial Ecology, 62(1), 99-108
Open this publication in new window or tab >>Active uptake of kleptoplastids by Dinophysis caudata from its ciliate prey Myrionecta rubra
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2011 (English)In: Aquatic Microbial Ecology, ISSN 0948-3055, E-ISSN 1616-1564, Vol. 62, no 1, p. 99-108Article in journal (Refereed) Published
Abstract [en]

We verified an active uptake of kleptoplastids in the toxic and bloom-forming dinoflagellatesof the genus Dinophysis from its preferred prey, the ciliate Myrionecta rubra, using a quantitativereal-time PCR technique. During a 65 d starvation/feeding experiment with Dinophysis caudata,changes in plastid 16S rRNA, plastid autofluorescence and plastid/nuclear DNA ratio throughthe cell cycle were followed with quantitative real-time PCR and flow cytometry. During starvation,the cultures initially showed a rapid growth and a 3.5-fold increase of number of cells ml–1, while atthe same time, plastid DNA cell–1 showed a 3.5-fold decrease, and a 3.6-fold decrease in phycoerythrinfluorescence cell–1. The decrease in plastid DNA cell–1 d–1 closely followed culture growth rate(Pearson correlation, r = 0.91), indicating that existing plastids were diluted within the growing populationand that no new plastids were synthesised by the cells. When starved cells were re-fed by theciliate M. rubra on Days 43 to 51 of the experiment, plastid DNA cell–1 increased 7-fold up to 14 00016S DNA copies per cell, thereby directly revealing the kleptoplastic behaviour. The implication isthat not only availability of the prey M. rubra itself, but also the supply of suitable kleptoplastidsmight be an important controlling factor for Dinophysis spp. bloom formation and decline.

National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-10619 (URN)10.3354/ame01459 (DOI)
External cooperation:
Available from: 2011-02-07 Created: 2011-02-07 Last updated: 2017-12-11Bibliographically approved
Kaczala, F., Salomon, P., Marques, M., Granéli, E. & Hogland, W. (2011). Effects from log-yard stormwater runoff on the microalgae Scenedesmus subspicatus: Intra-storm magnitude and variability. Journal of Hazardous Materials, 185(2-3), 732-739
Open this publication in new window or tab >>Effects from log-yard stormwater runoff on the microalgae Scenedesmus subspicatus: Intra-storm magnitude and variability
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2011 (English)In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 185, no 2-3, p. 732-739Article in journal (Refereed) Published
Abstract [en]

This paper describes the effects posed by stormwater runoff from an industrial log-yard on the microalgae Scenedesmus subspicatus. The effects of stormwater runoff sampled during two rain events were determined by exposing S. subspicatus cells to different concentrations (% v:v) of each sample. The effects were measured as the percentage change in growth rates in relation to a control culture after exposure times of 24, 48, 72 and 96h. The runoff from the first rain event had no negative effects to S.subspicatus, posing in most cases growth stimulation, whereas the runoff from the second rain event inhibited algae growth. Differences in runoff physico-chemical characteristics combined with the hydrological factors of each rain event explained these opposite effects. The hypothesis of toxic first flush phenomenon was confirmed in the second rain event on the basis of normalized inhibitory effects and runoff volume. It was found that 42, 51 and 50% of the inhibitory effects during exposures of 24, 48 and 72h are associated with the initial 4% of the total discharged volume. The fact that negative effects were observed in the two runoff events analyzed here, raises concern about the potential environmental threats posed by runoff originated from wood-based industrial areas during the entire hydrological year.

Keywords
toxicity, first flush, wood-industry, stormwater, growth inhibition
National Category
Natural Sciences
Research subject
Natural Science, Environmental Science
Identifiers
urn:nbn:se:lnu:diva-7136 (URN)10.1016/j.jhazmat.2010.09.080 (DOI)2-s2.0-78649968690 (Scopus ID)
Available from: 2010-08-12 Created: 2010-08-12 Last updated: 2017-12-12Bibliographically approved
Granéli, E. & Salomon, P. (2010). Factors influencing allelopathy and toxicity in Prymnesium parvum. Journal of the American Water Resources Association, 46, 108-120
Open this publication in new window or tab >>Factors influencing allelopathy and toxicity in Prymnesium parvum
2010 (English)In: Journal of the American Water Resources Association, ISSN 1093-474X, E-ISSN 1752-1688, Vol. 46, p. 108-120Article in journal (Refereed) Published
Abstract [en]

Some microalgae are able to kill or inhibit nutrient-competing microalgae, a process called allelopathy. Inhibiting or killing competitors enable these species to monopolize limiting resources, such as nitrogen and phosphorus. Prymnesium parvum is known to produce such allelopathic compounds, substances that seem identical to the ichthyotoxins identified from this species. Biotic and abiotic environmental factors influence not only growth rates but also toxin/allelopathic compounds production by P. parvum cells. Toxin production, as well as allelopathy, including grazer deterrence, increases dramatically in light, temperature, or nutrient stressed P. parvum cells. Correspondingly, toxicity and allelopathy may decrease, or cease completely, if cells are grown with high amounts of N and P in balanced proportions. However, even under nutrient (N and P) sufficient conditions, P. parvum is able to produce toxins/allelopathic compounds, with negative effects on other phytoplankton species or grazers, if cells densities of P. parvum are high relative to other species. This negative effect might shift the plankton community to more toxin resistant species. Filtrates from nutrient-deficient P. parvum cultures have almost the same strong negative effect on grazers and other phytoplankton species as when Prymnesium cells are grown together with the target organisms. Eutrophication, the increased input of N and P to aquatic ecosystems, besides increasing nutrient concentrations, is usually provoking unbalanced N:P condition for the optimal growth of phytoplankton, deviating from the Redfield ratio, i.e., the phytoplankton cellular nitrogen to phosphorus ratio, N:P = 16:1 (by atoms) or 7.2:1 (by weight). Eutrophication thus both enhances P. parvum growth and increases production of toxins and allelopathic compounds. Supplying N-deficient or P-deficient P. parvum cells with the deficient nutrient reduces toxicity to less than half within 24 h after additions. As P. parvum is mixotrophic, uptake of dissolved or particulate organic N (DON or PON) can also reduce toxicity and allelopathy in the same manner as addition of inorganic N to N-starved cells. In conclusion, P. parvum, by increasing its toxicity and allelopathic ability under poor environmental conditions, outcompetes the co-occurring phytoplankton species.

National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-2160 (URN)10.1111/j.1752-1688.2009.00395.x (DOI)
External cooperation:
Available from: 2010-04-06 Created: 2010-04-06 Last updated: 2017-12-12Bibliographically approved
Axelsson Olsson, D., Svensson, L., Olofsson, J., Salomon, P., Waldenström, J., Ellström, P. & Olsen, B. (2010). Increase in Acid Tolerance of Campylobacter jejuni through Coincubation with Amoebae. Applied and Environmental Microbiology, 76(13), 4194-4200
Open this publication in new window or tab >>Increase in Acid Tolerance of Campylobacter jejuni through Coincubation with Amoebae
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2010 (English)In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 76, no 13, p. 4194-4200Article in journal (Refereed) Published
Abstract [en]

Campylobacter jejuni is a recognized and common gastrointestinal pathogen in most parts of the world. Human infections are often food borne, and the bacterium is frequent among poultry and other food animals. However, much less is known about the epidemiology of C. jejuni in the environment and what mechanisms the bacterium depends on to tolerate low pH. The sensitive nature of C. jejuni stands in contrast to the fact that it is difficult to eradicate from poultry production, and even more contradictory is the fact that the bacterium is able to survive the acidic passage through the human stomach. Here we expand the knowledge on C. jejuni acid tolerance by looking at protozoa as a potential epidemiological pathway of infection. Our results showed that when C. jejuni cells were coincubated with Acanthamoeba polyphaga in acidified phosphate-buffered saline (PBS) or tap water, the bacteria could tolerate pHs far below those in their normal range, even surviving at pH 4 for 20 h and at pH 2 for 5 h. Interestingly, moderately acidic conditions (pH 4 and 5) were shown to trigger C. jejuni motility as well as to increase adhesion/internalization of bacteria into A. polyphaga. Taken together, the results suggest that protozoa may act as protective hosts against harsh conditions and might be a potential risk factor for C. jejuni infections. These findings may be important for our understanding of C. jejuni passage through the gastrointestinal tract and for hygiene practices used in poultry settings.

National Category
Microbiology
Research subject
Ecology, Microbiology
Identifiers
urn:nbn:se:lnu:diva-7087 (URN)10.1128/AEM.01219-09 (DOI)2-s2.0-77954258414 (Scopus ID)
Available from: 2010-08-10 Created: 2010-08-10 Last updated: 2017-12-12Bibliographically approved
Salomon, P., Granéli, E., Neves, M. & Rodriguez, E. (2009). Infection by Amoebophrya spp. parasitoids of dinoflagellates in a tropical marine coastal area. Aquatic Microbial Ecology, 55(2), 143-153
Open this publication in new window or tab >>Infection by Amoebophrya spp. parasitoids of dinoflagellates in a tropical marine coastal area
2009 (English)In: Aquatic Microbial Ecology, ISSN 0948-3055, E-ISSN 1616-1564, Vol. 55, no 2, p. 143-153Article in journal (Refereed) Published
Abstract [en]

Infection of marine dinoflagellates by the parasitic dinoflagellate Amoebophrya spp. plays an important role in population dynamics and carbon flow in marine food webs. It has been extensively reported that Amoebophrya parasitoids occur in temperate coastal areas of the northern hemisphere; however, little is known about their distribution and importance in tropical areas and southern oceans. We used an rRNA-based, fluorescent in situ hybridization assay to detect Amoebophrya spp. infections during the decline of a late-summer dinoflagellate population dominated by Ceratium falcatiforme in a tropical coastal area of the southern Atlantic Ocean subjected to recurrent upwelling-downwelling cycles. Conditions during our survey were typical of downwelling when oligotrophic waters dominate the area. C. falcatiforme was the most infected host, with a prevalence averaging 2% over the study area at the beginning of sampling. At a fixed sampling station monitored over 4 wk, Amoebophrya prevalence escalated from 1 to 7% over a 6 d period, concomitant to a 94% decrease in host cell numbers. Infection by Amoebophrya was estimated to have killed ca. 11% of the host cell population within this period; thus, parasitism was not the main factor behind the C. falcatiforme population decline. Estimates based on biovolume calculations indicate that ca. 6.5% of the carbon in the decaying C. falcatiforme population was transformed into parasitoid dinospores, which became available to tintinnid ciliates that were abundant during our survey. Such a trophic link might be relevant in tropical oligotrophic waters when the system is characterized by a microbial food web structure.

National Category
Ecology
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-2090 (URN)10.3354/ame01293 (DOI)
External cooperation:
Available from: 2010-04-06 Created: 2010-04-06 Last updated: 2017-12-12Bibliographically approved
Granéli, E., Weberg, M. & Salomon, P. (2008). Harmful algal blooms of allelopathic species: the role of eutrophication. Harmful Algae, 8, 94-102
Open this publication in new window or tab >>Harmful algal blooms of allelopathic species: the role of eutrophication
2008 (English)In: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 8, p. 94-102Article in journal (Refereed) Published
National Category
Natural Sciences
Research subject
Ecology, Aquatic Ecology
Identifiers
urn:nbn:se:lnu:diva-2086 (URN)
External cooperation:
Available from: 2010-04-06 Created: 2010-04-06 Last updated: 2017-12-12Bibliographically approved
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