9 research outputs found

    Cleaning up seas using blue growth initiatives : Mussel farming for eutrophication control in the Baltic Sea

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    Eutrophication is a serious threat to aquatic ecosystems globally with pronounced negative effects in the Baltic and other semi-enclosed estuaries and regional seas, where algal growth associated with excess nutrients causes widespread oxygen free “dead zones” and other threats to sustainability. Decades of policy initiatives to reduce external (land-based and atmospheric) nutrient loads have so far failed to control Baltic Sea eutrophication, which is compounded by significant internal release of legacy phosphorus (P) and biological nitrogen (N) fixation. Farming and harvesting of the native mussel species (Mytilus edulis/trossulus) is a promising internal measure for eutrophication control in the brackish Baltic Sea. Mussels from the more saline outer Baltic had higher N and P content than those from either the inner or central Baltic. Despite their relatively low nutrient content, harvesting farmed mussels from the central Baltic can be a cost-effective complement to land-based measures needed to reach eutrophication status targets and is an important contributor to circularity. Cost effectiveness of nutrient removal is more dependent on farm type than mussel nutrient content, suggesting the need for additional development of farm technology. Furthermore, current regulations are not sufficiently conducive to implementation of internal measures, and may constitute a bottleneck for reaching eutrophication status targets in the Baltic Sea and elsewhere. Highlights • Mussel farming is a viable internal measure to address Baltic Sea eutrophication. • Rates of nutrient removal depend on salinity at the regional scale and food availability at the local scale. • Cost effectiveness of nutrient removal by mussel farming depends also on farm type. • Total farm area needed for achieving HELCOM nutrient reduction targets is realistic

    Trombotsüütide agregatsiooni inhibeerimine B6-vitamiini vitameeridega in vitro koronaarhaigetel

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    B6-vitamiin inhibeerib trombotsüütide agregatsiooni ja samal ajal kaitseb ka veresoone endoteelirakke kahjustuste eest. Töös uuriti B6-vitamiini vitameeride püridoksiini (PN), püridoksamiini (PM), püridoksaali (PL) ja püridoksaalfosfaadi (PLP) toimeid trombotsüütide agregatsioonile koronaarhaigetel võrdlevalt nii optilise kui ka impedantsmeetodiga in vitro. Mõlema meetodi puhul ei erinenud B6-vitamiini vitameeride IC50 väärtused märkimisväärselt. Kuna erinevad B6-vitamiini vitameerid esinevad vereplasmas korraga, uuriti ka nende koostoimet. Eraldi võetuna inhibeerivad nad trombotsüütide agregatsiooni millimolaarstetes kontsentratsioonides, kombinatsioonides on nad tõhusad juba mikromolaarsetes kontsentratsioonides. Selline tulemus viitab B6-vitamiini vitameeride võimalikule rollile aterotromboosi kujunemisel. Eesti Arst 2008; 87(12):923−92

    Data from: Predicting the cover and richness of intertidal macroalgae in remote areas: a case study in the Antarctic Peninsula

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    1. Antarctica is an iconic region for scientific explorations as it is remote and a critical component of the global climate system. Recent climate change causes dramatic retreat of ice in Antarctica with associated impacts to its coastal ecosystem. These anthropogenic impacts have a potential to increase habitat availability for Antarctic intertidal assemblages. Assessing the extent and ecological consequences of these changes requires us to develop accurate biotic baselines and quantitative predictive tools. 2. In this study, we demonstrated that satellite based remote sensing, when used jointly with in-situ ground-truthing and machine learning algorithms, provides a powerful tool to predict the cover and richness of intertidal macroalgae. 3. The salient finding was that the Sentinel-based remote sensing described a significant proportion of variability in the cover and richness of Antarctic macroalgae. The highest performing models were for macroalgal richness and the cover of brown and green algae as opposed to the model of red algal cover. 4. When expanding the geographical range of the ground-truthing, even involving only a few sample points, it becomes possible to potentially map other Antarctic intertidal macroalgal habitats and monitor their dynamics. This is a significant milestone as logistical constraints are an integral part of the Antarctic expeditions. The method has also a potential in other remote coastal areas where extensive in-situ mapping is not feasible

    data

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    SHEET DATA Cover of substrate types and cover (%) and richness of macroalgal taxonomic groups along with values of the bottom of atmosphere reflectance at different spatial resolution (in metres) at an indicative wavelength. SHEET EXTERNAL VALIDATION DATASET Percent coverage of different macroalgal taxonomic group or macroalgal richness estimated by our BRT modelling together with that estimated during a separate field survey

    Random forest assessment of correlation between environmental factors and genetic differentiation of populations: Case of marine mussels Mytilus

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    Summary: The novel machine learning technique Random Forest (RF) was used to test if the genetic differentiation of populations of marine species may be related to any of the key environmental variables known to shape species distributions. The study was performed in North and Baltic Sea characterized by strong gradients of environmental factors and almost continuous distributions of Mytilus mussel populations. Assessment of the species identity was performed using four nuclear DNA markers, and previously published single nucleotide polymorphism (SNP) data. A general pattern of cline variation was observed with increasing Mytilus trossulus share towards the eastern Baltic Sea. Average allele share rose to 61% in Höga Kusten, Gulf of Bothnia. All Baltic Sea samples revealed a strong introgression of Mytilus edulis and a limited introgression of M. trossulus through the Danish Straits.The studied environmental variables described 67 and 68% of the variability in the allele frequencies of M. edulis and M. trossulus. Salinity defined over 50% of the variability in the gene frequencies of the studied Mytilus spp. populations. Changes along this environmental gradient were not gradual but instead a significant shift from gene dominance was found at a salinity of 12 PSU. Water temperature and the trophic status of the sea area had only moderate association with the gene frequencies. The obtained results showed that the novel machine learning technique can be successfully used for finding correlations between genetic differentiation of populations and environmental variables and for defining the functional form of these linkages. Keywords: Marine environment, Spatial distribution, Seascape genetics, Nuclear DNA markers EFbis, Glu-5′, ITS, M7 and Single Nucleotide Polymorphism, Baltic Se

    Cleaning up seas using blue growth initiatives: Mussel farming for eutrophication control in the Baltic Sea

    Get PDF
    Eutrophication is a serious threat to aquatic ecosystems globally with pronounced negative effects in the Baltic and other semi-enclosed estuaries and regional seas, where algal growth associated with excess nutrients causes widespread oxygen free “dead zones” and other threats to sustainability. Decades of policy initiatives to reduce external (land-based and atmospheric) nutrient loads have so far failed to control Baltic Sea eutrophication, which is compounded by significant internal release of legacy phosphorus (P) and biological nitrogen (N) fixation. Farming and harvesting of the native mussel species (Mytilus edulis/trossulus) is a promising internal measure for eutrophication control in the brackish Baltic Sea. Mussels from the more saline outer Baltic had higher N and P content than those from either the inner or central Baltic. Despite their relatively low nutrient content, harvesting farmed mussels from the central Baltic can be a cost-effective complement to land-based measures needed to reach eutrophication status targets and is an important contributor to circularity. Cost effectiveness of nutrient removal is more dependent on farm type than mussel nutrient content, suggesting the need for additional development of farm technology. Furthermore, current regulations are not sufficiently conducive to implementation of internal measures, and may constitute a bottleneck for reaching eutrophication status targets in the Baltic Sea and elsewhere. Highlights • Mussel farming is a viable internal measure to address Baltic Sea eutrophication. • Rates of nutrient removal depend on salinity at the regional scale and food availability at the local scale. • Cost effectiveness of nutrient removal by mussel farming depends also on farm type. • Total farm area needed for achieving HELCOM nutrient reduction targets is realistic
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