| 1. |
- Abbott, Benjamin W., et al.
(författare)
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Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire : an expert assessment
- 2016
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Ingår i: Environmental Research Letters. - : IOP Publishing. - 1748-9326. ; 11:3
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Tidskriftsartikel (refereegranskat)abstract
- As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate change. Results suggest that contrary to model projections, total permafrost-region biomass could decrease due to water stress and disturbance, factors that are not adequately incorporated in current models. Assessments indicate that end-of-the-century organic carbon release from Arctic rivers and collapsing coastlines could increase by 75% while carbon loss via burning could increase four-fold. Experts identified water balance, shifts in vegetation community, and permafrost degradation as the key sources of uncertainty in predicting future system response. In combination with previous findings, results suggest the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario but that 65%-85% of permafrost carbon release can still be avoided if human emissions are actively reduced.
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| 2. |
- Abiven, Samuel, et al.
(författare)
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Biochar amendment increases maize root surface areas and branching : a shovelomics study in Zambia
- 2015
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Ingår i: Plant and Soil. - : Springer Science and Business Media LLC. - 0032-079X .- 1573-5036. ; 395:1-2, s. 45-55
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Tidskriftsartikel (refereegranskat)abstract
- Positive crop yield effects from biochar are likely explained by chemical, physical and/or biological factors. However, studies describing plant allometric changes are scarcer, but may be crucial to understand the biochar effect. The main aim of the present study is to investigate the effect of biochar on root architecture under field conditions in a tropical setting. The presented work describes a shovelomics (i.e., description of root traits in the field) study on the effect of biochar on maize root architecture. Four field experiments we carried out at two different locations in Zambia, exhibiting non-fertile to relatively fertile soils. Roots of maize crop (Zea mays L.) were sampled from treatments with fertilizer (control) and with a combination of fertilizer and 4 t.ha(-1) maize biochar application incorporated in the soil. For the four sites, the average grain yield increase upon biochar addition was 45 +/- 14 % relative to the fertilized control (from 2.1-6.0 to 3.1-9.1 ton ha(-1)). The root biomass was approximately twice as large for biochar-amended plots. More extensive root systems (especially characterized by a larger root opening angle (+14 +/- 11 %) and wider root systems (+20 +/- 15 %)) were observed at all biochar-amended sites. Root systems exhibited significantly higher specific surface areas (+54 +/- 14 %), branching and fine roots: +70 +/- 56 %) in the presence of biochar. Biochar amendment resulted in more developed root systems and larger yields. The more extensive root systems may have contributed to the observed yield increases, e.g., by improving immobile nutrients uptake in soils that are unfertile or in areas with prolonged dry spells.
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| 3. |
- Abramsson-Zetterberg, Lilianne
(författare)
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Strongly heated carbohydrate-rich food is an overlooked problem in cancer risk evaluation
- 2018
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Ingår i: Food and Chemical Toxicology. - : Elsevier BV. - 0278-6915 .- 1873-6351. ; 121, s. 151-155
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Tidskriftsartikel (refereegranskat)abstract
- A cascade of compounds is produced when foodstuffs are heated at high temperatures but only a few of these compounds have been identified and quantified. In this study data are evaluated regarding differences in the micronucleus frequency of human erythrocytes (fMNs) in peripheral blood (a known biomarker of genotoxicity) in individuals that consumed either high- or low-heated food during a 4-day period. Concomitantly, acrylamide (aa) levels were measured in the food that the participants consumed. The obtained fMNs in this human study are compared with the fMNs in mice after comparable exposure levels of pure aa. The results of this comparison showed several hundred times higher fMNs in humans compared with mice. With an assumed linear correlation between an increased genotoxic effect and cancer, our data suggest that aa only represents a fraction of all carcinogenic compounds produced in heated carbohydrate-rich food. Consequently, our daily intake of carbohydrate-rich food heated at high temperatures might be responsible for one-fifth of the rate of the total cancer risk. One sentence summary: A biomarker of genotoxicity indicates the risk of cancer to be some hundred-fold greater in heated carbohydrate-rich food than the risk calculated from animal studies on pure acrylamide.
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| 4. |
- Abramsson-Zetterberg, Lilianne, et al.
(författare)
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The synthetic food colouring agent Allura Red AC (E129) is not genotoxic in a flow cytometry-based micronucleus assay in vivo
- 2013
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Ingår i: Food and Chemical Toxicology. - : Elsevier BV. - 0278-6915 .- 1873-6351. ; 59, s. 86-89
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Tidskriftsartikel (refereegranskat)abstract
- The safety of several azo colouring agents, used as food additives, has during the years been questioned. Allura Red AC (E129) has in some publications been classified as genotoxic. In fact, in the European Union, Allura Red is permitted as a food additive in human food, but, surprisingly, it was not acceptable as an additive for use in animal feed. In this study we have evaluated whether Allura Red is genotoxic using a flow cytometer-based micronucleus assay in peripheral blood of mice. Male FVB mice were given a single intra-peritoneal injection of various doses of Allura Red and sacrificed at 46 h after treatment. The tested doses were 0, 100, 200, 400, 600, 800, 1000, 1500, and 2000 mg/kg body weight (b.w.). Each dose group constituted three mice, except for in the dose group of 1000 mg/kg b.w., which constituted four mice. Blood samples were collected and the frequency of micronucleated polychromatic erythrocytes (fMNPCE) and the cell proliferation (%PCE) was determined. The analyses did not show any significant difference in the %PCE or in the fMNPCE. Consequently, under the testing circumstances one can conclude that Allura Red is not genotoxic.
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| 5. |
- Adler, Anneli, et al.
(författare)
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Lignin-first biorefining of Nordic poplar to produce cellulose fibers could displace cotton production on agricultural lands
- 2022
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Ingår i: Joule. - : Elsevier BV. - 2542-4351. ; 6:8, s. 1845-1858
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Tidskriftsartikel (refereegranskat)abstract
- Here, we show that lignin-first biorefining of poplar can enable the production of dissolving cellulose pulp that can produce regenerated cellulose, which could substitute cotton. These results in turn indicate that agricultural land dedicated to cotton could be reclaimed for food production by extending poplar plantations to produce textile fibers. Based on climate-adapted poplar clones capable of growth on marginal lands in the Nordic region, we estimate an environmentally sustainable annual biomass production of ∼11 tonnes/ha. At scale, lignin-first biorefining of this poplar could annually generate 2.4 tonnes/ha of dissolving pulp for textiles and 1.1 m3 biofuels. Life cycle assessment indicates that, relative to cotton production, this approach could substantially reduce water consumption and identifies certain areas for further improvement. Overall, this work highlights a new value chain to reduce the environmental footprint of textiles, chemicals, and biofuels while enabling land reclamation and water savings from cotton back to food production.
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| 6. |
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Agrarhistoria på många sätt : 28 studier om människan och jorden. Festskrift till Janken Myrdal på hans 60-årsdag
- 2009
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- Den överväldigande majoriteten av alla människor har varit verksamma i arbetet med jord och skog. Än idag är detta helt nödvändigt för vår överlevnad. Idag ställs även krav på landskapets biologiska och estetiska värden. Allt talar för att vi är i stort behov av agrarhistorisk kunskap. Boken ökar vår kunskap om dess kärna - om jorden, djuren och redskapen - men även de sociala, kulturella och politiska förhållandena som påverkat jordbruket. Bokens alla författare, både svenska och utländska, gör oss medvetna om mängden av agrarhistoriska källor och metoder. denna stora antologi är tillägnad Janken Myrdal, agrarhistoriens främste representant i Sverige, som låtit de mest skiftande och överraskande källmaterial och metoder komma till användning i sitt arbete.
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| 7. |
- Ahlbeck Bergendahl, Ida, et al.
(författare)
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Determining the effects of duration and recency of exposure to environmental enrichment
- 2016
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Ingår i: Applied Animal Behaviour Science. - : Elsevier BV. - 0168-1591 .- 1872-9045. ; 176, s. 163-169
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Tidskriftsartikel (refereegranskat)abstract
- Experience can help animals adapt their behaviour to fit the environment or conditions that they find themselves in. Understanding how and when experience affects behaviour is important for the animals we rear in captivity. This is particularly true when we rear animals with the intent of releasing them into the wild as part of population rehabilitation and conservation efforts. We investigated how exposure to a changing, more complex environment promotes behavioural development in juvenile trout. Four groups of fish were compared; (i) fish that were maintained without enrichment, (ii) fish that were exposed to an early period of enrichment, but were then returned to a plain environment, (iii) fish that were maintained in plain conditions, but were then exposed to enrichment towards the end of the rearing phase, (iv) a group that were kept in enriched conditions throughout the 12 week rearing period. We then assessed fish anxiety levels, their spatial learning ability, and the capacity of the fish to find their way through a barrier where different routes were presented across 4 different trials. Fish that experienced enriched conditions for the longest duration had superior spatial learning abilities, and they were better at finding the correct route to get past the barrier than fish from the remaining three treatments. Positive effects on behaviour were, however, also found in the fish that only experienced enrichment in the last part of the rearing period, compared to the control, or fish exposed to early enrichment. No effect of enrichment was found on levels of anxiety in any of the groups.
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| 8. |
- Ahlbeck, Ida, et al.
(författare)
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Evaluating fish diet analysis methods by individual-based modelling
- 2012
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Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - 0706-652X .- 1205-7533. ; 69:7, s. 1184-1201
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Tidskriftsartikel (refereegranskat)abstract
- Knowledge of diet compositions is important in ecological research. There are many methods available and numerous aspects of diet composition. Here we used modelling to evaluate how well different diet analysis methods describe the true diet of fish, expressed in mass percentages. The methods studied were both basic methods (frequency of occurrence, dominance, numeric, mass, points) and composite indices (Index of Relative Importance, Comparative Feeding Index). Analyses were based on both averaged stomach content of individual fish and on pooled content from several fish. Prey preference, prey size, and evacuation rate influenced the performance of the diet analysis methods. The basic methods performed better than composite indices. Mass and points methods produced diet compositions most similar to the true diet and were also most robust, indicating that these methods should be used to describe energetic-nutritional sources of fish.
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| 9. |
- Ahlqvist, Ola, et al.
(författare)
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Formalized interpretation of compound land use objects – Mapping historical summer farms from a single satellite image
- 2012
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Ingår i: Journal of Land Use Science. - : Taylor & Francis. - 1747-423X .- 1747-4248. ; 7:1, s. 89-107
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Tidskriftsartikel (refereegranskat)abstract
- Notions of land cover relating to physical landscape characters are readily captured by satellite imagery. Land use on the other hand relates more to the societal aspects of a landscape. We argue that much of the spatial configuration of landscape characters is related to land use and that satellite data can be used to represent and investigate interpretations of land use. We propose and demonstrate the joint use of a novel SRPC procedure for satellite imagery together with an explicit representation of category semantics. We use these two mechanisms to identify a collection of conceptual spaces related to land use on Swedish historic summer farms. We also outline a framework for analysis of the relations between two separate ways of knowing: the machine-based knowledge and the human, mental knowledge. An evaluation demonstrates that satellite images can be used to identify land use processes as a mixture of land cover objects occurring in particular spatial contextual relationships closely tied to the land use category semantics. This opens up an unexplored possibility for research on vague spatial ontologies and questions on how to formally articulate different interpretations of space, land use, and other branches of spatial social science.
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| 10. |
- Ahmadi Afzadi, Masoud, et al.
(författare)
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Genome-wide expression analysis suggests a role for jasmonates in the resistance to blue mold in apple
- 2018
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Ingår i: Plant growth regulation (Print). - : Springer Science and Business Media LLC. - 0167-6903 .- 1573-5087. ; 85:3, s. 375-387
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Tidskriftsartikel (refereegranskat)abstract
- Blue mold, caused by the necrotrophic fungal pathogen Penicillium expansum, causes serious postharvest losses in apple, and threatens human health through production of the potent mycotoxin patulin. Recent studies indicate a quantitative control of resistance against this disease in apple cultivars. A whole genome apple microarray covering 60k transcripts was used to identify gene(s) that appear to be differentially regulated between resistant and susceptible cultivars in P. expansum-infected fruits. A number of potential candidates was encountered among defense- and oxidative stress-related genes, cell wall modification and lignification genes, and genes related to localization and transport. Induction of one cell wall-related gene and three genes involved in the 'down-stream' flavonoid biosynthesis pathway, demonstrates the fundamental role of the cell wall as an important barrier, and suggests that fruit flavonoids are involved in the resistance to blue mold. Moreover, exogenous application of the plant hormone methyl jasmonate (MeJA) reduced the symptoms resulting from inoculating apples with P. expansum. This is the first report linking MeJA and activation of cell wall and flavonoid pathway genes to resistance against blue mold in a study comparing different cultivars of domesticated apple. Our results provide an initial categorization of genes that are potentially involved in the resistance mechanism, and should be useful for developing tools for gene marker-assisted breeding of apple cultivars with an improved resistance to blue mold.
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