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How climate change impacts the habitat building vegetation in the Baltic Sea : How are the species bladderwrack & common eelgrass impacted by climate change in the Baltic Sea?Axelsson, Sophia January 2022 (has links)
The world's seas are without a doubt being changed by global warming, affecting all species, causing ecosystem changes. The overall low biodiversity in the Baltic Sea leads to sensitive unique qualities. Understanding how climate change in the Baltic Sea will affect key species is important to understanding how the Baltic Sea coastal environment will look in the future. Fucus vesiculosus, and Zostera marina, are key habitat building vegetation in the Baltic Sea, building up most of the canopies by the coasts on rocky and sandy bottoms. How are these species affected by climate change in the Baltic Sea? The result showed that both Fucus and Zostera growth is stimulated during most of the year with rising temperatures, but during summer heatwaves inhibit the plants, raising the mortality. Fucus will migrate more south, as the Baltic Sea will likely become fresher, and Zostera will continue to thrive if nutrients are reduced. Both species will experience die-offs during summer heatwaves. / Världens hav förändras utan tvekan av den globala uppvärmningen, vilket påverkar alla arter och leder till ekosystem förändringar. Den övergripande låga biologiska mångfalden i Östersjön leder till känsliga unika förhållanden. Att förstå hur klimatförändringarna i Östersjön kommer att påverka nyckelarter är viktigt för att förstå hur Östersjöns kustmiljö kommer att se ut i framtiden. Fucus vesiculosus och Zostera marina, är viktiga habitatsbildande växter i Östersjön, som bygger upp majoriteten av ekosystemen vid kusterna på steniga och sandiga bottnar. Hur påverkas dessa arter av klimatförändringar i Östersjön? Resultatet visade att tillväxten av både Fucus och Zostera stimuleras under större delen av året med stigande temperaturer, men under sommaren hämmar värmeböljor växterna, vilket ökar dödligheten. Huvudslutsatserna är att Fucus kommer att vandra mer söderut, eftersom Östersjön med största sannolikhet kommer att bli sötare från norr, och Zostera kommer fortsätta trivas om näringsmängden minskar. Båda arterna kommer drabbas av dödsfall under värmeböljor på sommaren.
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Avalia??o da genotoxicidade e do potencial osteog?nico de polissacar?deos sulfatados de algas marinhas / Evaluation of the genotoxicity and osteogenic potential of seaweed sulfated polysaccharidesSousa, Ang?lica Fernandes Gurgel de 26 May 2017 (has links)
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Previous issue date: 2017-05-26 / Os problemas relacionados com defeitos ?sseos continuam a motivar a busca de terapias mais eficazes. Assim, a combina??o de biomateriais, c?lulas-tronco e mol?culas bioativas fazem parte das ferramentas usadas pela medicina regenerativa para alcan?ar esse objetivo. Diversos estudos j? mostraram o potencial osteog?nico dos polissacar?deos sulfatados (PSs) extra?dos de macroalgas marinhas. Entre eles, o fucoidan, isolado da alga marrom Fucus vesiculosus, ? o mais estudado, sendo j? comercializado por algumas empresas. As algas verdes tamb?m s?o fonte de PSs, mas estas s?o ainda pouco exploradas para aplica??es na regenera??o ?ssea. Em geral, as aplica??es cl?nicas dos PSs extra?dos de algas ainda s?o limitadas devido ? escassez de estudos sobre os seus efeitos, como por exemplo, o potencial genot?xico ? desconhecido na maioria dos casos. Assim, neste trabalho avaliamos a atividade osteog?nica 1) do Fucoidan de F. vesiculosus (um extrato comercializado pela Sigma), 2) das amostras ricas em PSs obtidas do subfracionamento do fucoidan comercial, e 3) do extrato rico em PSs extra?dos da alga verde Caulerpa sertularioides usando como modelo c?lulas-tronco humanas isoladas da geleia de Wharton de cord?es umbilicais (CTMH-GW). Estudou-se tamb?m o potencial genot?xico dos extratos totais de F. vesiculosus e C. sertularioides e posteriormente, da subfra??o do fucoidan que apresentou maior potencial osteog?nico, utilizando do ensaio de micron?cleo com bloqueio da citocinese (CBMN) na linhagem CHO-K1. Os ensaios de redu??o do MTT evidenciaram que as amostras ricas em PSs n?o apresentaram citotoxicidade significativa ao longo de 72 h, at? 10 ?g.mL-1. Os ensaios de atividade da fosfatase alcalina (ALP) e de mineraliza??o sugerem que as amostras ricas em PSs possuem atividades osteog?nicas diferentes: a subfra??o do fucoidan FUC 0.5 (5 ?g.mL-1) foi a que apresentou melhor resultado, aumentando 124% a atividade da ALP em rela??o ao controle positivo (c?lulas mantidas em meio osteog?nico). J? o extrato total de C. sertularioides (5 ?g.mL-1) aumentou 192% a atividade da ALP. Adicionalmente, todas as amostras testadas induziram o ac?mulo de c?lcio na matriz extracelular. Quanto ? genotoxicidade, os resultados do ensaio CBMN sugerem que, nas condi??es testadas, estas amostras n?o s?o genot?xicas, indicando que podem ser uma alternativa para terapias de regenera??o ?ssea. / Problems related with bone defects continue to motivate the search for more effective therapies. Thus, the combination of biomaterials, stem cells and bioactive molecules is part of the tools used by regenerative medicine to achieve this goal. Several studies have already shown the osteogenic potential of sulfated polysaccharides (SPs) extracted from marine macroalgae. Among them, fucoidan, isolated from brown algae Fucus vesiculosus, is the most studied, and is already commercialized by some companies. Green algae are also a source of SPs, but these are even more unexploited in the scope of bone regeneration. In general, the clinical applications of SPs from algae are very limited, because studies on their effects are scarce, for example, their genotoxic effects are unknown in most cases. Thus, in this work, we evaluated the osteogenic activity of Fucoidan from F. vesiculosus (an extract commercialized by Sigma), 2) SPs-rich samples obtained from subfractionation of commercial fucoidan, and 3) SPs-enriched extract from green algae Caulerpa Sertularioides, using human mesenchymal stem cells isolated from the Wharton jelly of umbilical cords (CTMH-GW) as cell model. It was also studied the genotoxic potential of the total extracts of F. vesiculosus and C. sertularioides, using the cytokinesis block micronucleus assay (CBMN) in the line CHO-K1. The genotoxicity of fucoidan?s subfraction that presented greater osteogenic potential was also evaluated. The MTT reduction assays showed that SPs-enriched samples did not show significant cytotoxicity over 72 h, up to 10 ?g.mL-1. Alkaline phosphatase (ALP) activity and mineralization assays suggest that SPs-enriched samples have different osteogenic activities: fucoidan subfraction FUC 0.5 (5 ?g.mL-1) showed the best result, increasing 124% the ALP activity in relation to the positive control (cells maintained in osteogenic medium). The total extract of C. sertularioides (5 ?g.mL-1) increased the ALP activity by 192%. In addition, all samples tested induced calcium accumulation in the extracellular matrix. Concerning to genotoxicity, CBMN assay results suggest that, under the tested conditions, these samples are not genotoxic, indicating their potential as alternative bone regeneration therapy.
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Long-term changes in macroalgal vegetation on the Swedish coast : An evaluation of eutrophication effects with special emphasis on increased organic sedimentationEriksson, Britas Klemens January 2002 (has links)
<p>In this thesis I examine and evaluate the effects of a documented large-scale eutrophication on macroalgal vegetation on the Swedish coast. During the past century the load of nutrients has increased manifold in the Baltic Sea area, increasing primary production and organic sedimentation significantly. By re-investigating a unique reference material of macroalgal vegetation from the 1940-60s and by conducting new diving studies at the same sites, I showed that long-term trends in macroalgal community composition and species’ distributions are consistent with changes expected from an increased nutrient availability. In the Öregrund archipelago (northern Baltic Sea), I documented a declined depth distribution of the dominant canopy forming alga, <i>Fucus vesiculosus</i>, and an increased abundance of opportunistic ephemeral algae compared to 52-53 years ago. In the Gullmar Fjord area (Skagerrak), trends included increased abundances of functional groups with opportunistic algae, decreased abundances of large perennial algae and a general decline in the depth distribution of the vegetation compared to 36-57 years ago. Sediment removal experiments in the northern Baltic Sea confirmed the hypothesis that sedimentation influences macroalgal community composition. Species depending on short periods of reproduction were clearly favoured by sediment removal, especially <i>F. vesiculosus</i> that seemed limited in depth by the local sediment load. Species with long continuous periods of dispersal by spores and/or fragments (for example the ephemerals <i>Cladophora glomerata</i>, <i>Ceramium tenuicorne</i> and <i>Enteromorpha</i> spp.) were more tolerant to the natural sediment load. In general, sediment removal favoured macroalgal establishment and development, indicating that variation in the natural sediment load is an important constraint for sublittoral rocky-shore macroalgal community development. I conclude by suggesting that the documented long-term changes in macroalgal vegetation on the Swedish coast partly are explained by an increased organic sedimentation in these areas.</p>
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Improvements in the dosimetric models of selected benthic organismsCaffrey, Emily Amanda 02 October 2012 (has links)
The International Commission on Radiological Protection (ICRP) has modeled twelve
reference animal and plant (RAP) species using simple geometric shapes in Monte���Carlo
(MCNP) based simulations. The focus has now shifted to creating voxel phantoms of
each RAP to advance the understanding of radiation interactions in nonhuman biota.
The work contained herein presents results for the voxel phantom of the Dungeness crab,
Metacarcinus magister, the Sand Dab, Limanda limanda, and the brown seaweed, Fucus
vesiculosus, and details a generalized framework for creating voxel phantoms of the other
RAPs. Absorbed fractions (AFs) for all identified organs were calculated at several
discrete initial energies: 0.01, 0.015, 0.02, 0.03, 0.05, 0.1, 0.2, 0.5, 1.0, 1.5, 2.0, and 4.0
MeV for photons and 0.1, 0.2, 0.4, 0.5, 0.7, 1.0, 1.5, 2.0 and 4.0 MeV for electrons. AFs
were then tabulated for each organ as a source and target at each energy listed above.
AFs whose error exceeded 5% are marked with an underline in the data tables; AFs
whose error was higher than 10% are shown in the tabulated data as a dashed line. The
AF���s were highly dependent on organ mass and geometry. For photons above 0.5 MeV
and electrons above 0.2-0.4 MeV a nontrivial amount of energy escapes the source organ. / Graduation date: 2013
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Long-term changes in macroalgal vegetation on the Swedish coast : An evaluation of eutrophication effects with special emphasis on increased organic sedimentationEriksson, Britas Klemens January 2002 (has links)
In this thesis I examine and evaluate the effects of a documented large-scale eutrophication on macroalgal vegetation on the Swedish coast. During the past century the load of nutrients has increased manifold in the Baltic Sea area, increasing primary production and organic sedimentation significantly. By re-investigating a unique reference material of macroalgal vegetation from the 1940-60s and by conducting new diving studies at the same sites, I showed that long-term trends in macroalgal community composition and species’ distributions are consistent with changes expected from an increased nutrient availability. In the Öregrund archipelago (northern Baltic Sea), I documented a declined depth distribution of the dominant canopy forming alga, Fucus vesiculosus, and an increased abundance of opportunistic ephemeral algae compared to 52-53 years ago. In the Gullmar Fjord area (Skagerrak), trends included increased abundances of functional groups with opportunistic algae, decreased abundances of large perennial algae and a general decline in the depth distribution of the vegetation compared to 36-57 years ago. Sediment removal experiments in the northern Baltic Sea confirmed the hypothesis that sedimentation influences macroalgal community composition. Species depending on short periods of reproduction were clearly favoured by sediment removal, especially F. vesiculosus that seemed limited in depth by the local sediment load. Species with long continuous periods of dispersal by spores and/or fragments (for example the ephemerals Cladophora glomerata, Ceramium tenuicorne and Enteromorpha spp.) were more tolerant to the natural sediment load. In general, sediment removal favoured macroalgal establishment and development, indicating that variation in the natural sediment load is an important constraint for sublittoral rocky-shore macroalgal community development. I conclude by suggesting that the documented long-term changes in macroalgal vegetation on the Swedish coast partly are explained by an increased organic sedimentation in these areas.
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En undersökning av potentiellt odlingsbara makroalger i Hanöbukten, ÖstersjönPersson, Beatrice January 2023 (has links)
In the future, the cultivation of algae for food may become increasingly important in Sweden. But this area is still new in Europe and most of the harvest today comes from wild stocks. In Sweden, cultivation is only available on the west coast, but research is underway to see if it is possible to start cultivating macroalgae in the Baltic Sea as well. The Baltic Sea has completely different biological conditions than the west coast, and one of the challenges is the low salinity, which limits the species that can live in the Baltic Sea. This is something that the Marine Center in Simrishamn is also researching in the project Tångkusten, of which this study is a part of. The purpose of this study is to use a literature study to compile available knowledge about which algae that has the potential to be cultivated in the future and what the life cycles of these algae look like. An inventory of the macroalgae found locally in Hanöbukten was also carried out. Based on this information, possible cultivation methods and the advantages of each species are discussed, but also the challenges that may arise. The results showed that the most abundant species were filamentous brown algae, bladder wrack and saw wrack . The species deemed most cultivable are gut weed and sea lettuce. Clawed fork weed, bladder wrack and saw wrack are also considered to have some cultivation potential. Among the biggest challenges are the growth of epiphytic algae and finding a suitable site for cultivation. / Projektet Tångkusten på Marint centrum i Simrishamn
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Physiological adaptations in two ecotypes of Fucus vesiculosus and in Fucus radicans with focus on salinityGylle, A Maria January 2011 (has links)
The in origin intertidal marine brown alga Fucus vesiculosus L. grow permanently sublittoral in the brackish Bothnian Sea, side by side with the recently discovered F. radicans L. Bergström et L. Kautsky. Environmental conditions like salinity, light and temperature are clearly different between F. vesiculosus growth sites in the Bothnian Sea (4-5 practical salinity units, psu; part of the Baltic Sea) and the tidal Norwegian Sea (34-35 psu; part of the Atlantic Ocean). The general aims of this thesis were to compare physiological aspects between the marine ecotype and the brackish ecotype of F. vesiculosus as well as between the two Bothnian Sea species F. vesiculosus and F. radicans. The result in the study indicates a higher number of water soluble organic compounds in the marine ecotype of F. vesiculosus compared to the brackish ecotype. These compounds are suggested to be compatible solutes and be due to an intertidal and sublittoral adaptation, respectively; where the intertidal ecotype needs the compounds as a protection from oxygen radicals produced during high irradiation at low tide. The sublittoral ecotype might have lost the ability to synthesize these compound/compounds due to its habitat adaptation. The mannitol content is also higher in the marine ecotype compared to the brackish ecotype of F. vesiculosus and this is suggested to be due to both higher level of irradiance and higher salinity at the growth site. 77 K fluorescence emission spectra and immunoblotting of D1 and PsaA proteins indicate that both ecotypes of F. vesiculosus as well as F. radicans have an uneven ratio of photosystem II/photosystem I (PSII/PSI) with an overweight of PSI. The fluorescence emission spectrum of the Bothnian Sea ecotype of F. vesiculosus however, indicates a larger light-harvesting antenna of PSII compared to the marine ecotype of F. vesiculosus and F. radicans. Distinct differences in 77 K fluorescence emission spectra between the Bothnian Sea ecotype of F. vesiculosus and F. radicans confirm that this is a reliable method to use to separate these species. The marine ecotype of F. vesiculosus has a higher photosynthetic maximum (Pmax) compared to the brackish ecotype of F. vesiculosus and F. radicans whereas both the brackish species have similar Pmax. A reason for higher Pmax in the marine ecotype of F. vesiculosus compared to F. radicans is the greater relative amount of ribulose-1.5-bisphosphate carboxylase/oxygenase (Rubisco). The reason for higher Pmax in marine ecotype of F. vesiculosus compare to the brackish ecotype however is not due to the relative amount of Rubisco and further studies of the rate of CO2 fixation by Rubisco is recommended. Treatments of the brackish ecotype of F. vesiculosus in higher salinity than the Bothnian Sea natural water indicate that the most favourable salinity for high Pmax is 10 psu, followed by 20 psu. One part of the explanation to a high Pmax in 10 psu is a greater relative amount of PsaA protein in algae treated in 10 psu. The reason for greater amount of PsaA might be that the algae need to produce more ATP, and are able to have a higher flow of cyclic electron transport around PSI to serve a higher rate of CO2 fixation by Rubisco. However, studies of the rate of CO2 fixation by Rubisco in algae treated in similar salinities as in present study are recommended to confirm this theory. / Fucus vesiculosus L. (Blåstång) är en brunalg som i huvudsak växer i tidvattenzonen i marint vatten men arten klarar också att växa konstant under ytan i det bräckta Bottenhavet. Norska havet och den del av Bottenhavet, där algerna är insamlade i denna studie, har salthalterna 34-35 psu (praktisk salthaltsenhet) respektive 4-5 psu. F. radicans L. Bergström et L. Kautsky (Smaltång) är en nyligen upptäckt art (2005) som har utvecklats i Bottenhavet. F. radicans och Bottenhavets ekotyp av F. vesiculosus växer sida vid sida och har tidigare ansetts vara samma art. Sett till hela Östersjön, så ändras ytans salthalt från 25 till 1-2 psu mellan Östersjöns gräns mot Kattegatt och norra Bottenviken. Den låga salthalten i Östersjön beror på det höga flödet av sötvatten från älvarna och på ett litet inflödet av saltvatten i inloppet vid Kattegatt. Salthaltsgradienten är korrelerad med antalet arter som minskar med minskad salthalt. Östersjön är ett artfattigt hav och de arter som finns är till stor del en blandning av söt- och saltvattenarter. Det finns bara ett fåtal arter som är helt anpassade till bräckt vatten och F. radicans är en av dem. Exempel på miljöskillnader för F. vesiculosus i Norska havet och i Bottenhavet är salthalten, tidvattnet, ljuset och temperaturen. Tidvattnet i Norska havet gör att algerna växlar mellan att vara i vattnet och på land, vilket utsätter algerna för stora ljusskillnader, snabba och stora temperaturväxlingar samt även torka. De alger som växer i Bottenhavet har däremot en jämnare och lägre temperatur, istäcke på vintern och mindre tillgång på ljus eftersom de alltid lever under vattenytan. Skillnaderna i miljön mellan växtplatserna leder till skillnader i fysiologiska anpassningar. Anledningen till att F. vesiculosus och F. radicans valdes som studieobjekt i denna avhandling är att de är viktiga nyckelarter i Bottenhavet. F. vesiculosus och F. radicans är de enda större bältesbildande alger som finns i det artfattiga ekosystemet och de används därför flitigt som mat, gömställe, parningsplats och barnkammare för t.ex. fisk. Att de är nyckelarter gör det angeläget att försöka förstå hur algerna är anpassade och hur de reagerar på miljöförändringar för att få veta hur de kan skyddas och bevaras. F. radicans inkluderades även för att se hur en naturlig art i Bottenhavet är anpassad i jämförelse med den invandrade F. vesiculosus. Marin F. vesiculosus inkluderades för att vara en artreferens från artens naturliga växtplats. Studien visar att det finns fler vattenlösliga organiska substanser (finns vissa organiska substanser som har en proteinskyddande funktion) i den marina ekotypen av of F. vesiculosus än i Bottenhavets ekotyp. Anledningen till detta föreslås vara en anpassning till att växa i tidvattenzonen. Vid lågvatten utsätts F. vesiculosus från Norska havet för starkt ljus, uttorkning, och snabba temperatur- växlingar vilket gör att den kan behöva dessa organiska substanser som skydd mot fria syreradikaler som bildas under lågvattenexponeringarna. F. vesiculosus från Bottenhavet har troligen mist förmågan att syntetisera dessa substanser på grund av anpassning till att hela tiden växa under ytan. Mängden mannitol (socker) är högre i den marina ekotypen av of F. vesiculosus än i Bottenhavets ekotyp. Detta föreslås bero på högre fotosyntetiskt maximum i F. vesiculosus från Norska havet jämfört med ekotypen från Bottenhavet. Skillnaden i fotssyntetiskt maximum är bland annat kopplat till ljus- och salthaltskillnaden på algernas växtplatser. Denna teori styrks av att både fotosyntesen och halten av mannitol ökar i Bottenhavets ekotyp när den behandlas i högre salthalt. Studien visar även att båda ekotyperna av F. vesiculosus samt F. radicans har ett ojämnt förhållande mellan fotosystem II och I (PSII och PSI) med en dominans av PSI. Denna slutsats är baserad på fluorescens emissions mätningar vid 77 K (-196 °C) och mätning av den relativa mängden D1 protein (motsvarar PSII) och PsaA protein (motsvarar PSI). F. vesiculosus från Bottenhavet visar ett emission spektrum som pekar mot en jämnare fördelning av PSII och PSI jämfört med den marina ekotypen och F. radicans. Detta stämmer dock inte med förhållandet mellan D1/PsaA som indikerar att alla tre har mer PSI än PSII. Förklaringen till avvikelsen mellan metoderna antas vara att F. vesiculosus från Bottenhavet har större ljus-infångande antennpigment än marin F. vesiculosus och F. radicans. De tydliga skillnaderna i 77 K fluorescens emission spektra mellan Bottenhavets F. vesiculosus och F. radicans visar att denna metod kan användas som säker artidentifiering. Den marina ekotypen av F. vesiculosus har högre fotosyntetiskt maximum än de båda arterna från Bottenhavet. Mätningar av den relativa mängden av enzymet Rubisco, viktigt för upptaget av koldioxid hos växter och alger, visar att mängden enzym är en sannolik förklaring till skillnaden i fotosyntetiskt maximum mellan den marina ekotypen av F. vesiculosus och F. radicans och detta är troligen en normal artskillnad. Mängden Rubisco kan dock inte förklara skillnaden i fotosyntetiskt maximum mellan de båda ekotyperna av F. vesiculosus. För att undersöka vad skillnaden mellan dessa två beror på så föreslås istället mätningar av Rubisco’s koldioxidfixeringshastighet. Det är en ökning av fotosyntetiskt maximum i Bottenhavets ekotyp av F. vesiculosus när den behandlas i högre salthalt (10, 20 och 35 psu) och det högsta fotosyntetiska maximumet uppmättes i alger som behandlats i 10 psu. Denna ökning beror inte på ökning i den relativa mängden av Rubisco. Ökningen i fotosyntesen speglas dock av en ökning av den relativa mängden PsaA. Detta antas bero på att det behövs mer energi i form av ATP och att en ökning av detta kan ske på grund av att mer PsaA kan driva den cykliska elektrontransporten i fotosyntesreaktionen. Ökat behov av ATP antas bero på en ökning av Rubisco aktiviteten men mätning av aktiviteten krävs för att bekräfta detta.
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