Institution
Swedish University of Agricultural Sciences
Education•Uppsala, Sweden•
About: Swedish University of Agricultural Sciences is a education organization based out in Uppsala, Sweden. It is known for research contribution in the topics: Population & Soil water. The organization has 13510 authors who have published 35241 publications receiving 1414458 citations. The organization is also known as: Sveriges Lantbruksuniversitet & SLU.
Topics: Population, Soil water, Species richness, Biodiversity, Picea abies
Papers published on a yearly basis
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TL;DR: Species richness was not affected by fire, whereas the evenness of species distributions of mycorrhizas was lower in the burned stands, suggesting that EM fungal communities show a high degree of continuity following low‐intensity wildfires.
Abstract: This study was conducted to evaluate the effects of wildfires on ectomycorrhizal (EM) fungal communities in Scots pine (Pinus sylvestris) stands. Below- and above-ground communities were analysed in terms of species richness and evenness by examining mycorrhizas and sporocarps in a chronosequence of burned stands in comparison with adjacent unburned late-successional stands. The internal transcribed spacer (ITS)-region (rDNA) of mycobionts from single mycorrhizas was digested with three restriction enzymes and compared with an ITS–restriction fragment length polymorphism (RFLP) reference database of EM sporocarps. Spatial variation seemed to be more prominent than the effects of fire on the EM fungal species composition. Most of the common species tended to be found in all sites, suggesting that EM fungal communities show a high degree of continuity following low-intensity wildfires. Species richness was not affected by fire, whereas the evenness of species distributions of mycorrhizas was lower in the burned stands. The diversity of EM fungi was relatively high considering that there were only three EM tree species present in the stands. In total, 135 EM taxa were identified on the basis of their RFLP patterns; 66 species were recorded as sporocarps, but only 11 of these were also recorded as mycorrhizas. The species composition of the below-ground community of EM fungi did not reflect that of the sporocarps produced. EM fungal species present in our ITS–RFLP reference database accounted for 54–99% of the total sporocarp production in the stands, but only 0–32% of the mycorrhizal abundance.
244 citations
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TL;DR: In this article, tocopherol levels in vegetable oils seem to be close to the optimal levels needed for the stabilization of these oils, and the presence of other antioxidants in the oils, e.g. carotenoids, phenolic compounds, and Maillard reaction products, may synergize with tocophels and minimize this loss of efficacy.
Abstract: The oxidative stability of vegetable oils is determined by their fatty acid composition and antioxidants, mainly tocopherols but also other non-saponifiable constituents. The effect of fatty acids on stability depends mainly on their degree of unsaturation and, to a lesser degree, on the position of the unsaturated functions within the triacylglycerol molecule. Vegetable oils contain tocopherols and tocotrienols, especially α- and γ-tocopherols, as their main antioxidants. The antioxidant behavior of tocopherols represents a complex phenomenon as they are efficient antioxidants at low concentrations but they gradually lose efficacy as their concentrations in the vegetable oils increase. The “loss of efficacy” of tocopherols, sometimes referred to as a “pro-oxidant effect”, is witnessed by an increase in the rate of oxidation during the induction period, despite elongation of this phase. The phenomenon is much obvious for α-tocopherol, but is also evident for other tocopherols. In agreement with nature's wisdom, the tocopherol levels in vegetable oils seem to be close to the optimal levels needed for the stabilization of these oils. The presence of other antioxidants in the oils, e.g. carotenoids, phenolic compounds, and Maillard reaction products, may synergize with tocopherols and minimize this loss of efficacy.
244 citations
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TL;DR: It is difficult to establish straightforward relationships between nutrient management, surplus, losses and environmental impact, and agronomic and environmental reference or target values need to be established for different production systems, geographical areas and elements.
243 citations
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TL;DR: The hypothesis that some ectomycorrhizal fungi--Cortinarius species in particular--may play an important role in decomposition of complex organic matter, linked to their mobilization of organically bound N is supported.
Abstract: In northern forests, belowground sequestration of nitrogen (N) in complex organic pools restricts nutrient availability to plants. Oxidative extracellular enzymes produced by ectomycorrhizal fungi may aid plant N acquisition by providing access to N in macromolecular complexes. We test the hypotheses that ectomycorrhizal Cortinarius species produce Mn-dependent peroxidases, and that the activity of these enzymes declines at elevated concentrations of inorganic N. In a boreal pine forest and a sub-arctic birch forest, Cortinarius DNA was assessed by 454-sequencing of ITS amplicons and related to Mn-peroxidase activity in humus samples with- and without previous N amendment. Transcription of Cortinarius Mn-peroxidase genes was investigated in field samples. Phylogenetic analyses of Cortinarius peroxidase amplicons and genome sequences were performed. We found a significant co-localization of high peroxidase activity and DNA from Cortinarius species. Peroxidase activity was reduced by high ammonium concentrations. Amplification of mRNA sequences indicated transcription of Cortinarius Mn-peroxidase genes under field conditions. The Cortinarius glaucopus genome encodes 11 peroxidases - a number comparable to many white-rot wood decomposers. These results support the hypothesis that some ectomycorrhizal fungi--Cortinarius species in particular--may play an important role in decomposition of complex organic matter, linked to their mobilization of organically bound N.
243 citations
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TL;DR: Carboxylate shifts are often important for car boxylate coordinated metal clusters; they allow the metals to achieve different coordination modes in redox reactions, in the case of reduced R2 these carboxylates shifts allow the formation of accessible reaction sites for dioxygen.
243 citations
Authors
Showing all 13653 results
Name | H-index | Papers | Citations |
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Svante Pääbo | 147 | 407 | 84489 |
Lars Klareskog | 131 | 697 | 63281 |
Stephen Hillier | 129 | 1138 | 83831 |
Carol V. Robinson | 123 | 670 | 51896 |
Jun Yu | 121 | 1174 | 81186 |
Peter J. Anderson | 120 | 966 | 63635 |
David E. Clapham | 119 | 382 | 58360 |
Angela M. Gronenborn | 113 | 568 | 44800 |
David A. Wardle | 110 | 409 | 70547 |
Agneta Oskarsson | 106 | 766 | 40524 |
Jack S. Remington | 103 | 481 | 38006 |
Hans Ellegren | 102 | 349 | 39437 |
Per A. Peterson | 102 | 356 | 35788 |
Malcolm J. Bennett | 99 | 439 | 37207 |
Gunnar E. Carlsson | 98 | 466 | 32638 |