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Schneider S.C.,Norwegian Institute for Water Research
Science of the Total Environment | Year: 2011

Acidification continues to be a major impact in freshwaters of northern Europe, and the biotic response to chemical recovery from acidification is often not a straightforward process. The focus on biological recovery is relevant within the context of the EU Water Framework Directive, where a biological monitoring system is needed that detects differences in fauna and flora compared to undisturbed reference conditions. In order to verify true reference sites for biological analyses, expected river pH is modeled based on Ca and TOC, and 94% of variability in pH at reference sites is explained by Ca alone, while 98% is explained by a combination of Ca and TOC. Based on 59 samples from 28 reference sites, compared to 547 samples from 285 non-reference sites, the impact of calcium and total organic carbon (TOC) on benthic algae species composition, expressed as acidification index periphyton (AIP), is analyzed. Rivers with a high Ca concentration have a naturally higher AIP, and TOC affects reference AIP only at low Ca concentrations. Four biological river types are needed for assessment of river acidification in Norway based on benthic algae: very calcium-poor, humic rivers (Ca < 1. mg/l and TOC > 2. mg/l); very calcium-poor, clear rivers (Ca < 1. mg/l and TOC < 2. mg/l); calcium-poor rivers (Ca between 1 and 4. mg/l); moderately calcium rich rivers (Ca > 4. mg/l). A biological assessment system for river acidification in Norway based on benthic algae is presented, following the demands of the Water Framework Directive. © 2010 Elsevier B.V. Source

Rott E.,University of Innsbruck | Schneider S.C.,Norwegian Institute for Water Research
Science of the Total Environment | Year: 2014

Alpine and Nordic rivers are often considered as being among the most pristine in Europe. Nevertheless, acidification and eutrophication impact surface waters in these regions. Soft-bodied, i.e. non-diatom, benthic algae are used as indicators for eutrophication and acidification in both Norway and Austria, but consistency of indicator values has never been tested. We compared species optima with respect to pH, conductivity, total phosphorus (TP), and NO3 --N concentration for 21 species, derived from geographically and temporally extensive datasets from Norway and Austria, respectively. The ranges of all four measured parameters were different between Norway and Austria, with Austria having generally higher values for all measured parameters. Optima for all 21 species with respect to pH, conductivity and NO3 --N were significantly different between Norway and Austria, while 5 of the 21 taxa showed no significant differences for TP. Nevertheless, species optima for Norway and Austria were significantly correlated with each other for TP, pH and conductivity. This indicates that positions of species optima relative to each other may be stable across ecoregions, in spite of the absolute values of species optima being different. In contrast, optima with respect to NO3 --N were not correlated, possibly suggesting a lesser importance of NO3 - in shaping benthic algal assemblages than TP and pH. We conclude that the use of eutrophication and acidification models across different ecoregions may give meaningful results, but requires regional testing of species optima. © 2013 Elsevier B.V. Source

Larssen T.,Norwegian Institute for Water Research
Environmental Pollution | Year: 2010

Chinese reservoirs may behave differently with respect to Hg mobilization compared to the much studied cases in North America and Europe. © 2009 Elsevier Ltd. All rights reserved. Source

Sonstebo J.H.,Norwegian Institute for Water Research | Rohrlack T.,University of Oslo
Applied and Environmental Microbiology | Year: 2011

Populations of the cyanobacterium Planktothrix comprise multiple coexisting oligopeptide chemotypes that can behave differently in nature. We tested whether this population subdivision can, in principle, be driven by parasitic chytrid fungi, which are almost neglected agents of Planktothrix mortality. Two chytrid strains, Chy-Lys2009 and Chy-Kol2008, were isolated from Planktothrix-dominated lakes in Norway. The two strains shared 98.2% and 86.2% of their 28S and internal transcribe spacer rRNA gene sequences, respectively. A phylogenetic analysis placed them in the order Rhizophydiales family Angulomycetaceae. Chy-Lys2009 and Chy-Kol2008 could completely lyse Planktothrix cultures within days, while they failed to infect other filamentous cyanobacteria. The effect on Planktothrix was chemotype dependent, and both chytrid strains showed distinct chemotype preferences. These findings identify chytrid fungi infecting Planktothrix as highly potent and specialized parasites which may exert strong selective pressure on their hosts. According to established hypotheses on host-parasite coevolution, parasitism with the above properties may result in subdivision of Planktothrix populations into coexisting chemotypes and periodic shifts in the relative Planktothrix chemotype composition. These predictions are in agreement with field observations. Moreover, a genetic analysis verified the co-occurrence of Chy-Lys2009 and Chy-Kol2008 or related chytrid strains along with distinct Planktothrix chemotypes in at least one water body. Our findings are consistent with a scenario where chytrid parasitism is one driving force of Planktothrix population subdivision, which in turn leads to polymorphism in parasitic chytrid fungi. Future studies should test the validity of this scenario under field conditions. © 2011, American Society for Microbiology. Source

Agency: Cordis | Branch: H2020 | Program: RIA | Phase: LCE-15-2015 | Award Amount: 15.97M | Year: 2016

STEMM-CCS is an ambitious research and innovation project on geological carbon dioxide (CO2) storage that will deliver new insights, guidelines for best practice, and tools for all phases of the CO2 storage cycle at ocean Carbon Capture and Storage (CCS) sites. It brings together the main operator (Shell) of the worlds first commercial scale full-chain ocean demonstration CCS project (Peterhead Project) with the leading scientific and academic researchers in the field of ocean CCS. The work performed in STEMM-CCS will add value to this existing operational programme, and fill gaps in future capability by providing generically applicable definitive guides, technologies and techniques informing how to select a site for CCS operations, how to undertake a risk assessment, how best to monitor the operations, how to provide information on fluxes and quantification of any leakage; necessary for the European Union Emissions Trading Scheme (ETS) and to guide mitigation/remediation actions. All of this information will be used to better communicate the case for offshore CCS, with a particular focus on communities directly and indirectly impacted. During STEMM-CCS we will perform a simulated CO2 leak beneath the surface sediments at the site to be used for CCS as part of the Peterhead project. This experiment will be used to test CO2 leak detection, leak quantification, impact assessment, and mitigation/remediation decision support techniques currently at the Technology Readiness Level (TRL) stage 4-5 and support their development to a higher TRL. In addition, using new geophysical approaches STEMM-CCS will develop tools to assess leakage from natural geological features (e.g. chimneys) and engineered structures such as abandoned wells. The Peterhead project will commence during the life of STEMM-CCS and so a unique aspect is the focus on a real-world ocean CCS site covering its initial phases of implementation, with direct involvement of industrial partners.

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