| 1. |
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| 2. |
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| 3. |
- Ahnström, Johan, et al.
(författare)
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Farmers' Interest in Nature and Its Relation to Biodiversity in Arable Fields
- 2013
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Ingår i: International Journal of Ecology. - : Hindawi Publishing Corporation. - 1687-9708 .- 1687-9716.
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Tidskriftsartikel (refereegranskat)abstract
- Biodiversity declines in farmland have been attributed to intensification of farming at the field level and loss of heterogeneity at the landscape level. However, farmers are not solely optimizing production; their actions are also influenced by social factors, tradition and interest in nature, which indirectly influence biodiversity but rarely are incorporated in studies of farmland biodiversity. We used social science methods to quantify farmers’ interest in nature on 16 farms with winter wheat fields in central Sweden, and combined this with biodiversity inventories of five organism groups (weeds, carabid beetles, bumblebees, solitary bees, and birds) and estimates of landscape composition andmanagement intensity at the field level.Agricultural intensity,measured as crop density, and farmers’ interest in nature explained variation in biodiversity, measured as the proportion of the regional species richness found on single fields. Interest in nature seemed to incorporate many actions taken by farmers and appeared to be influenced by both physical factors, for example, the surrounding landscape, and social factors, for example, social motivations.This study indicates that conservation of biodiversity in farmland, and design of new agri-environmental subsidy systems, would profit from taking farmers’ interest in nature and its relation to agricultural practices into account.
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| 4. |
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| 5. |
- Ahrné, Karin, et al.
(författare)
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Dagfjärilar i naturbetesmarker, kraftledningsgator, på hyggen och skogsbilvägar : betydelse för miljöövervakning
- 2011
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Ett förändrat och intensifierat jordbruk har bland annat lett till att naturbetesmarker och andra gräsmarksbiotoper minskat i odlingslandskapet. Detta har fått till följd att många arter knutna till öppna gräsmarker minskat, däribland fåglar, växter och dagfjärilar. Dagfjärilar svarar snabbt på förändringar både i miljön och klimatet och kan därför vara viktiga indikatorarter för miljöövervakning. I år startar en nationell övervakning av dagfjärilar med hjälp av volontärer och de senaste fem åren har dagfjärilar inventerats i ängs- och betesmarker inom den nationella inventeringen av landskapet (NILS). För att få en rättvisande bild av hur situationen ser ut för dagfjärilar i Sverige kan det vara viktigt att systematiskt inventera olika typer av miljöer, inte enbart ängs- och betesmarker eller känt artrika platser. I den här studien jämför vi artrikedom, individantal och artsammansättning av dagfjärilar (Rophalocera) och bastardsvärmare (Zyganidaea) i naturbetesmarker och tre typer av öppna biotoper i skogslandskapet; hyggen, kraftledningsgator och skogsbilvägar. Vi delar också in fjärilarna efter val av värdväxt och flygtid på säsongen för att se om det finns några skillnader mellan biotoperna vad gäller art- och individrikedom inom dessa grupper. Vi undersöker hur mängden skog och betesmark inom det omgivande landskapet påverkar dagfjärilsfaunan på de olika platserna och hur många inventeringstillfällen (3, 5 eller 7) som krävs för att få tillförlitliga data på artrikedomen på en plats. Våra resultat visar att artsammansättningen av fjärilar skiljer sig mellan biotoperna och att alla bidrar med unika arter och således kompletterar varandra. Kraftledningsgatorhade både fler fjärilsarter och individer än de övriga biotoperna och hyggen och skogsbilvägar var lika art- och individrika som betesmarkerna. Det är därför viktigt att övervaka flera typer av miljöer och även skogsbiotoper inom framtida dagfjärilsövervakning. Eftersom alla tre skogsbiotoperna hyser en stor mångfald av fjärilar kan det vara värt att anpassa skötseln av dessa miljöer för att gynna fjärilar. I kraftledningsgator och skogsbilvägar som är relativt beständiga miljöer och som redan idag sköts med ett visst intervall är detta fullt möjligt. Betydelsen av antal inventeringstillfällen beror på vilken frågeställning man har. Vill man jämföra artrikedomen i olika miljöer eller studera förändring i artrikedom mellan år kan det kanske räcka med tre besök, men vill man ha en mer heltäckande bild av artrikedomen på en plats kan det sju eller fler besök spridda över säsongen
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| 6. |
- Akerstrom, Ulf, et al.
(författare)
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Comparison of Moisturizing Creams for the Prevention of Atopic Dermatitis Relapse: A Randomized Double-blind Controlled Multicentre Clinical Trial
- 2015
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Ingår i: Acta Dermato-Venereologica. - : Medical Journals Sweden AB. - 1651-2057 .- 0001-5555. ; 95:5, s. 587-592
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Tidskriftsartikel (refereegranskat)abstract
- Atopic dermatitis (AD) affects adults and children and has a negative impact on quality of life. The present multicentre randomized double-blind controlled trial showed a barrier-improving cream (5% urea) to be superior to a reference cream in preventing eczema relapse in patients with AD (hazard ratio 0.634, p = 0.011). The risk of eczema relapse was reduced by 37% (95% confidence interval (95% CI) 10-55%). Median time to relapse in the test cream group and in the reference cream group was 22 days and 15 days, respectively (p = 0.013). At 6 months 26% of the patients in the test cream group were still eczema free, compared with 10% in the reference cream group. Thus, the barrier-improving cream significantly prolonged the eczema-free time compared with the reference cream and decreased the risk of eczema relapse. The test cream was well tolerated in patients with AD.
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| 7. |
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| 8. |
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| 9. |
- Balk, Lennart, et al.
(författare)
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Widespread episodic thiamine deficiency in Northern Hemisphere wildlife
- 2016
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Ingår i: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Many wildlife populations are declining at rates higher than can be explained by known threats to biodiversity. Recently, thiamine (vitamin B-1) deficiency has emerged as a possible contributing cause. Here, thiamine status was systematically investigated in three animal classes: bivalves, ray-finned fishes, and birds. Thiamine diphosphate is required as a cofactor in at least five life-sustaining enzymes that are required for basic cellular metabolism. Analysis of different phosphorylated forms of thiamine, as well as of activities and amount of holoenzyme and apoenzyme forms of thiaminedependent enzymes, revealed episodically occurring thiamine deficiency in all three animal classes. These biochemical effects were also linked to secondary effects on growth, condition, liver size, blood chemistry and composition, histopathology, swimming behaviour and endurance, parasite infestation, and reproduction. It is unlikely that the thiamine deficiency is caused by impaired phosphorylation within the cells. Rather, the results point towards insufficient amounts of thiamine in the food. By investigating a large geographic area, by extending the focus from lethal to sublethal thiamine deficiency, and by linking biochemical alterations to secondary effects, we demonstrate that the problem of thiamine deficiency is considerably more widespread and severe than previously reported.
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| 10. |
- Berg, Björn, et al.
(författare)
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Sequestration of carbon in the humus layer of Swedish forests - direct measurements
- 2009
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Ingår i: Canadian Journal of Forest Research. - 0045-5067 .- 1208-6037. ; 39:5, s. 962-975
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Tidskriftsartikel (refereegranskat)abstract
- To determine sequestration rates of carbon dioxide (CO2) we calculated the carbon (C) storage rate in humus layers of Swedish forests with Podsolic soils, which account for 14.2 x 106 ha of the 22.7 x 106 ha of forested land in Sweden. Our data set covered 41 years of humus inventories and mean humus layer thickness in 82513 plots. We analysed three forest types: (i) all combinations of tree species, (ii) forests dominated (>70%) by Norway spruce (Picea abies (L.) Karst.), and (Ui) forests dominated (>70%) by Scots pine (Pinus sylvestris L.). To relate changes in humus layer thickness to land area we used the intersections in 25 km x 25 km grids and used kriging interpolation, permitting calculations for each forest type. For each intersection mean humus thickness for each year was calculated and regressed against time to obtain the rate of change. This rate, humus bulk density, and humus C concentration were used, to calculate sequestration rates. The mean sequestration rate was 251 kg C-ha-1'year1, which is higher than theoretical values. The sequestration rate was positively related to temperature sum, albeit including effects of forest management. The pine-dominated forest type had a mean rate of 283 kgCha⁁year-1, and. the spruce-dominated had a mean rate of 239 kg Cha-1-year1. Under similar site conditions, pine sequestered more C than spruce (difference of 71 kg Cha-1'year-1; p < 0.0001), showing the importance of this type of ecosystem for C sequestration.
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| 11. |
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| 12. |
- Berg, Bengt-Åke
(författare)
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Livsmedelsindustrin under mellankrigstiden
- 2014
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Ingår i: Organiserad samverkan : svenska karteller under 1900-talet. - Möklinta : Gidlunds förlag. - 9789178448913 ; , s. 69-104
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 13. |
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| 14. |
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| 15. |
- Berg, Bengt-Åke, et al.
(författare)
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Samarbetets omfattning och aktörernas roll
- 2014
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Ingår i: Organiserad samverkan : svenska karteller under 1900-talet. - Möklinta : Gidlund. - 9789178448913 ; , s. 15-40
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 16. |
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| 17. |
- Berg, Bengt-Åke
(författare)
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Volatility, integration and grain banks : studies in harvests, rye prices and institutional development of the parish magasins in Sweden in the 18th and 19th centuries
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This study is the first to focus primarily on the Swedish parish magasins, the country’s most widespread credit institution in the last half of the 18th, and the first part of the 19th, century. During the Early Modern Period, grain price volatility was a matter of great concern. The parish magasins were conceived as a substitute for government action intended to stabilize grain prices and offer relief in case of crop failure. The thesis analyzes the problems of harvest variability and grain price fluctuations utilizing both theory and empirical evidence. It is concluded that market integration, especially by permitting imports, was more effective than inter-harvest storage in reducing the likelihood of high prices. Initially the peasants were sceptical of the new institution. Although the establishment of the magasinswas strictly speaking voluntary, substantial hierarchical pressure was applied. Once they had come into existence, however, the magasins evolved into a type of grain bank. The parishioners found them useful as a source of communal revenue at a time of rising need for local public expenditure for education and poor relief. In addition, the failure of the grain market to meet the needs of the peasantry created a demand for loans in kind. Although by no means ideal, in the absence of any superior institutions, themagasins provided valuable services. When improvements in both municipal finance and the functioning of the grain markets occurred in the second half of the 19th century, the magasins became obsolete. Both history and geography impact the formation of institutions. This study describes one such case of institutional development and attempts to explain why the outcome deviated from the original intention.
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| 18. |
- Berg, Mats, et al.
(författare)
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A Novel Formulation of Mometasone Furoate in Psoriasis Patients: A Multicenter, Randomized, Double-Blind Clinical Study
- 2013
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Ingår i: Advances in Therapy. - : Springer Science and Business Media LLC. - 0741-238X .- 1865-8652. ; 30:5, s. 503-516
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Tidskriftsartikel (refereegranskat)abstract
- Further formulations of mometasone furoate are needed for treatment of patients with plaque psoriasis to meet individual patient preferences. This has motivated the development of Ovixan(A (R)) (Galencia, Malmoe, Sweden), a formulation of mometasone furoate with different cosmetic properties than the commonly used formulation, Elocon(A (R)) (Merck [Schering Plough], Whitehouse Station, New Jersey, USA). This novel formulation of mometasone furoate was examined in a vasoconstrictor assay comparing its efficacy with that of Elocon. Subsequently, the new formulation was tested in a multicenter, randomized, double-blind clinical study in patients with plaque psoriasis. Healthy volunteers were included in the vasoconstrictor study. The treatments were randomly assigned to test fields on the forearms. The test fields were gently cleaned after treatment for 6 h. Skin color was measured during the following 24 h and area under the time curve was calculated. The clinical efficacy and tolerance of Ovixan was as compared to that of Elocon and their vehicles in a double-blind study in patients with plaque psoriasis. Patients with four symmetrically placed lesions on the arms or the legs were treated for 6 weeks. Primary endpoint was the change from baseline of the Total Severity Sign score for each treated lesion. The cosmetic characteristics of the two test preparations were assessed by an independent cosmetological institute. Ovixan was shown to have skin blanching potency almost identical to the vasoconstrictor potency of Elocon. Clinical equivalence of Ovixan to Elocon was demonstrated in the clinical study of the efficacy in patients with plaque psoriasis. A professional testing team clearly documented the cosmetic superiority of Ovixan as compared to Elocon. The results of the investigations show that Ovixan is equipotent to the commonly used formulation Elocon. However, the cosmetic properties are in favor of Ovixan. The effect of the cosmetic differences on patient preferences and patient adherence to prescribed treatment has to be investigated in further studies.
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| 19. |
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| 20. |
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| 21. |
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| 22. |
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| 23. |
- Berg, Sven, et al.
(författare)
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Experimental characterisation of CaCO3 powder mix for high-pressure compaction modelling
- 2010
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Ingår i: Powder Technology. - : Elsevier BV. - 0032-5910 .- 1873-328X. ; 203:2, s. 198-205
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Tidskriftsartikel (refereegranskat)abstract
- The mechanical properties of powders at high pressures are difficult to measure and therefore such data are rarely reported in open literature. Available test equipment mainly operates in the low-pressure region, 0-200 MPa. Calcite (CaCO3) is a mineral suitable for high-pressure processes, e.g. sintering of diamond compacts. It is also a very common material in the earth core and therefore of interest for geoscientists. In order to model the processes in the high-pressure region (above 1 GPa), knowledge of the mechanical properties of the powder in the entire pressure range is needed. Experimental studies have been conducted to investigate the pressure-density relationship of a CaCO3 powder and also to correlate the relative density to elastic and strength properties using experimental results. Further, a methodology has been introduced to provide a foundation for an elastic-plastic constitutive model. The mechanical behaviour of a CaCO3 powder mix has been investigated using the Brazilian disc test, uniaxial compression testing and closed die experiments. The experiments showed increasing elastic modulus and strength with increasing density. An empirical expression of the dependence of the bulk modulus on density has also been introduced.
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| 24. |
- Berg, Sven, et al.
(författare)
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Experimental characterization of CaCO3powder for use in compressible gaskets up to ultra-high pressure
- 2012
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Ingår i: Powder Technology. - : Elsevier BV. - 0032-5910 .- 1873-328X. ; 215-216, s. 124-131
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this study was to investigate the compaction properties for a CaCO3 powder mix up to ultra-high pressure (10GPa) and how these properties affect the gasket behaviour. Different parameters of the powder are investigated, i.e. initial density and internal moisture. A set-up, supporting the outer diameter of the compact, commonly used for gaskets in the belt apparatus was also investigated. The experimental results are in terms of pressure instrumentation in the Bridgman anvil apparatus together with load–displacement curves of the powder compacts. The instrumentation is done so that it can be used to calibrate constitutive models.
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| 25. |
- Berg, Sven, et al.
(författare)
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Frictional behaviour of CaCO3 powder compacts
- 2012
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Ingår i: Powder Technology. - : Elsevier BV. - 0032-5910 .- 1873-328X. ; 228, s. 429-434
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Tidskriftsartikel (refereegranskat)abstract
- During powder compaction processes friction has an influence on the final shape and properties of components. It is therefore important to understand how the friction influences the compaction process. Since detailed friction measurements of the powder compact-tool interface are rare, simulation models of the powder compaction process often involve a more accurate description of the frictional behaviour. This limits the accuracy of the simulated results. More accurate numerical models can give improved results, especially in regards to the evolution of density and its distribution within the powder compacts.This study is as a step towards more advanced friction models for powder compaction simulations. A universal tribometer has been used to investigate the frictional behaviour of contact interfaces between a carbide counter surface and CaCO3 powder compacts with different densities. Both static and dynamic frictional properties were measured in a variety of conditions to build a fundamental foundation for friction modelling in powder compaction simulations.The results show that increasing the powder compact density decreases the dynamic friction coefficient but that the static friction coefficient remains fairly constant. The measured friction coefficient can be used to improve the simulation of a powder compact process. Also investigated is the change in friction coefficient that occurs in the compaction process when the surfaces are worn such that loose powder appears in the interface between the tool and the powder compact. This behaviour is important to take into account to accurately describe the compaction process.
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| 26. |
- Berg, Sven, et al.
(författare)
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High pressure characterization and modelling of CaCO3 powder mix in the Bridgman anvil apparatus
- 2012
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Ingår i: High Pressure Research. - : Informa UK Limited. - 0895-7959 .- 1477-2299. ; 32:4, s. 490-508
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Tidskriftsartikel (refereegranskat)abstract
- For investigating high pressure sintering processes, numerical models can be used. This will demand material models which give realistic mechanical response throughout the whole parameter space of the actual process. As the pressures become higher, the material density approaches its full theoretical value and the elastic part of the material properties becomes increasingly important. In this investigation, Poisson's ratio was determined using ultrasonic pulse-echo measurements. A new elastic model and an improved plasticity model were implemented into a user-defined material subroutine in a finite element (FE) code. To experimentally investigate the load displacement response and pressure distribution in powder compacts during pressing, a pressure instrumented Bridgman anvil apparatus was used. Validation of the FE model was conducted against experimental data from pressing experiments using two different start densities. The results show that the simulation model is indeed capable of reproducing load–thickness curves and pressure profiles reasonable close to the experimental curves.
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| 27. |
- Berg, Sven, et al.
(författare)
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High-pressure compaction modelling of calcite (CaCO3) powder compact
- 2011
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Ingår i: Powder Technology. - : Elsevier BV. - 0032-5910 .- 1873-328X. ; 206:3, s. 259-268
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Tidskriftsartikel (refereegranskat)abstract
- Numerical simulation of manufacturing processes with working conditions at high pressure (above 1 GPa) requires constitutive data of the powder for the whole range of pressure and density. Most of the test apparatuses commonly used to obtain such data is only working in the lower pressure regions. Because of the absence of high-pressure data, many parameters have to be guessed or extrapolated. A material used in high-pressure applications is Calcite (CaCO3). The material can be used as an insulator in high-pressure capsules it is also a common material in the earth core. An apparatus often used to generate high pressure during compaction is the Bridgman anvil apparatus. In this work experimental tests with a Bridgman anvil set-up using Calcite powder discs with different thicknesses were done. A nonlinear elastic-plastic cap model was developed to model the behaviour of powder material from low pressure and loose state to high pressure and solid state. The constitutive model was implemented in a finite element code. The constitutive data were identified by optimization of experimental data. Validation was done by numerically reproduce the mechanical behaviour of uni-axially pressing Calcite to different pressure (up to 5 GPa) including unloading. The load-displacement curves, density distribution and the surface displacement were measured and compared to the finite element results. The results of the compaction simulations agree reasonably well with the experimental results.
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| 28. |
- Berg, Stefan, et al.
(författare)
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Sequence properties of the 1,2-diacylglycerol 3-glucosyltransferase from Acholeplasma laidlawii membranes : Recognition of a large group of lipid glycosyltransferases in eubacteria and archaea
- 2001
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Ingår i: Journal of Biological Chemistry. - 0021-9258 .- 1083-351X. ; 276:25, s. 22056-22063
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Tidskriftsartikel (refereegranskat)abstract
- Synthesis of the nonbilayer-prone α-monoglucosyldiacylglycerol (MGlcDAG) is crucial for bilayer packing properties and the lipid surface charge density in the membrane ofAcholeplasma laidlawii. The gene for the responsible, membrane-bound glucosyltransferase (alMGS) (EC 2.4.1.157) was sequenced and functionally cloned in Escherichia coli, yielding MGlcDAG in the recombinants. Similar amino acid sequences were encoded in the genomes of several Gram-positive bacteria (especially pathogens), thermophiles, archaea, and a few eukaryotes. All of these contained the typical EX7E catalytic motif of the CAZy family 4 of α-glycosyltransferases. The synthesis of MGlcDAG by a close sequence analog from Streptococcus pneumoniae (spMGS) was verified by polymerase chain reaction cloning, corroborating a connection between sequence and functional similarity for these proteins. However, alMGS and spMGS varied in dependence on anionic phospholipid activators phosphatidylglycerol and cardiolipin, suggesting certain regulatory differences. Fold predictions strongly indicated a similarity for alMGS (and spMGS) with the two-domain structure of the E. coli MurG cell envelope glycosyltransferase and several amphipathic membrane-binding segments in various proteins. On the basis of this structure, the alMGS sequence charge distribution, and anionic phospholipid dependence, a model for the bilayer surface binding and activity is proposed for this regulatory enzyme.
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| 29. |
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| 30. |
- Berg, Åke, et al.
(författare)
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Assessing agri-environmental schemes for semi-natural grasslands during a 5-year period: can we see positive effects for vascular plants and pollinators?
- 2019
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Ingår i: Biodiversity and Conservation. - : Springer Science and Business Media LLC. - 0960-3115 .- 1572-9710. ; 28, s. 3989-4005
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Tidskriftsartikel (refereegranskat)abstract
- An important function of agri-environmental schemes (AES) is to change management of pastures to better conserve biodiversity. However, the effects of most AES on biodiversity are poorly understood, especially when it comes to effects of AES management over time. The main aim of this study is to investigate if the species richness and abundance of grassland specialists of vascular plants and two important insect pollinator groups (bumblebees and butterflies) differ over time (5 years) in pastures with AES management (two value levels; general values and special values) and pastures without AES management. We also investigate if local vegetation characteristics and landscape composition relate to species richness in semi-natural grasslands. Using data from more than 400 sites we found that species richness of vascular plants (grassland specialists) was higher in pastures with AES management (for special and general values) compared to those without AES, which implies that these schemes do have value of the conservation of plant diversity. However, species richness and abundance of butterflies (grassland specialists) and bumblebees (all species) did not differ significantly among the three AES categories. We found no evidence that the type of AES management caused any changes in species richness of plants, butterflies or bumblebees during the 5 year period of our investigation. It appears that AES management that encourages uniform and minimum levels of grazing can have both positive and negative effects on biodiversity. For example, pollinators may benefit from a lower grazing intensity that could increase flower richness and heterogeneity in vegetation height. However, low grazing intensity may lead to increased cover of trees and shrubs, which can have negative effects for both insect pollinators and vascular plants. The effects of landscape composition were weak and only species richness of bumble bees were associated with landscape composition. Designing management regimes to maintain suitably heterogeneous vegetation layer, and continued long-term monitoring of biodiversity will be critical for safeguarding culturally and functionally important semi-natural grasslands.
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| 31. |
- Berg, Åke, et al.
(författare)
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Betydelsen av kraftledningsgator, skogsbilvägar och naturbetesmarker för fjärilar i olika landskapstyper
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I landskap dominerade av modernt jord- och skogsbruk är många arters livsmiljöer starkt fragmenterade vilket hotar deras långsiktiga överlevnad. Linjära element i landskapet antas kunna underlätta arters spridning och överlevnad i landskapet genom att fungera som spridningskällor och därmed minska de negativa effekterna av fragmenteringen. Kunskapen om i vilken utsträckning linjära landskapselement, som vägkanter och kraftledningsgator utgör spridningskällor (habitat som producerar överskott av individer) och/eller fungerar som funktionella spridningskorridorer är dålig. En av målsättningarna med denna undersökning var att undersöka om närhet till kraftledningsgator ökar art- och individrikedomen av fjärilar i andra biotoper. Vi gjorde detta genom att inventera fjärilar på 160 platser i 23 landskap i södra Sverige. I fjärilsinventeringen jämförde vi fjärilsfaunan i naturbetesmarker och skogsbilvägar på olika avstånd från kraftledningsgator. Dessutom jämförde vi fjärilsfaunan i kraftledningsgator (och naturbetesmarker och skogsbilvägar) i en gradient från relativt öppna landskap med jordbruksmark till skogsdominerade landskap. Vi gjorde även detaljerade studier av några arters rörelsemönster och beteende i några utvalda landskap (två i varje delstudie). Vi studerade i) flygbeteendet hos några utvalda arter i kraftledningsgator, betesmarker och längs vägar med syftet att analysera om andelen individer som uppvisade snabb flykt (spridning) och födosöksflykt skiljde sig mellan habitaten. Dessutom gjordes ii) experiment med utsläpp av fångade individer av ett urval av arter vid gränsen mellan en betesmark och andra habitat för att se om de föredrog att flyga genom betesmark, skog, ledningsgator eller åkermark. Kraftledningsgator tycktes fungera som spridningskälla för fjärilar i skogsbilvägar eftersom både art- och individrikedom var signifikant högre i skogsbilvägar och naturbetesmarker nära kraftledningsgator än i områden långt ifrån ledningsgatorna. Den positiva effekten av närheten till kraftledningsgator tycktes klinga av först vid avstånd på 700-800 m från ledningsgatorna, dvs kraftledningsgatorna hade en positiv effekt på fjärilsfaunan i områden som är mycket större än den areal de täcker. Dessutom var sammansättningen av arter liknande i områden nära och på avstånd från ledningsgatorna, vilket tyder på att ökningen i art- och individrikedom inte berodde på en ökning av arter som normalt inte förekommer i större omfattning på skogsbilvägarna och i naturbetesmarkerna. De analyser vi genomfört när det gäller rörelsemönster och beteenden de utvalda arterna tyder på att det är stor skillnad mellan olika arter, vissa arter (t.ex. pärlgräsfjäril) tycks använda ledningsgatorna för födosök (och därmed troligen också reproduktion), luktgräsfjäril kan enligt våra resultat möjligen också använda ledningsgatorna för spridningsflykt och skogsnätfjäril tycktes göra det. Det troliga är alltså att ledningsgatorna fungerar som spridningskorridorer för vissa arter, medan andra använder habitatet för reproduktion, vilket resulterar i att ledningsgatorna fungerar som spridningskällor (bra habitat) för närliggande habitat. Generellt ökade artrikedomen av fjärilar i naturbetesmarker och skogsbilvägar med ökande andel skog i landskapet. Skogslandskap innehåller mer alternativa habitat än landskap med mer åkermark. I motsats till våra förväntningar fann vi inga starka effekter av landskapets sammansättning (inom 1 km eller 6 km radie) för art- och individrikedom av fjärilar i ledningsgatorna. Detta indikerar att ledningsgatorna (till skillnad från de två andra habitaten) uppfyller kraven för ett flertal arter oavsett det omgivande landskapets sammansättning. I likhet med tidigare studier fann vi att ledningsgatorna var art- och individrikare än naturbetesmarker och skogsbilvägar, vilket bekräftar deras betydelse för fjärilsfaunan. Förutom att fokusera på ledningsgatornas roll som spridningskälla för fjärilar så utvärderade vi betydelsen av övriga habitatvariabler som t.ex. korridorernas bredd, markförhållanden och förekomst av träd och buskar för artrikedom av fjärilar i ledningsgator och skogsbilvägar. En faktor som var viktig för artrikedomen i dessa två habitat var korridorernas bredd (från <10m m i de smalaste vägarna – 200 m i de bredaste ledningsgatorna), vilket visar betydelsen av arealen öppet habitat i de studerade skogslandskapen. För skogsbilvägar kan den högre artrikedomen i breda vägar också bero på mikroklimatets betydelse (solsken och högre temperatur i breda vägar), vilket är en viktig faktor för fjärilar på nordliga latituder. I kraftledningsgator (25 – 200 m breda) är det troligt att den positiva effekten av korridorbredd, ända upp till 200 m, är en effekt av ökad habitatvariation som är kopplat till den större arealen öppet habitat. 4 Andra faktorer som var korrelerat till artrikedomen i både skogsbilvägar och ledningsgator var mängd lövsly längs transekten och mängd lövträd i de omgivande brynen. Detta kan bero på att flera arter är beroende av det skydd som buskarna erbjuder, vissa arter är också knutna till buskar och träd under larvstadiet. Markförhållandena (t.ex. näringsinnehåll) kan också påverka artrikedomen positivt, och lövträd indikerar goda näringsförhållanden (med förekomst av örter) i annars näringsfattiga barrskogsområden. I ledningsgatorna var artrikedomen negativt korrelerad med mängden lövträd (kopplat till tid sedan röjning). Detta indikerar att mer frekvent röjning i ledningsgator med en artrik eller värdefull fjärilsfauna med fördel kan ske oftare än vart 6-8 år som nu är standard i de flesta ledningsgatorna. Artrikedomen var låg i ledningsgator med torr mark och en vegetation dominerad av ris, d.v.s. specifik skötsel för att gynna fjärilsfaunan bör fokusera på breda ledningsgator med frisk-fuktig mark och en gräs-ört vegetation med blommande växter.
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| 32. |
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| 33. |
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| 34. |
- Berg, Åke, et al.
(författare)
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Butterflies in semi-natural pastures and power-line corridors - effects of flower richness, management, and structural vegetation characteristics
- 2013
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Ingår i: Insect Conservation and Diversity. - : Wiley. - 1752-458X .- 1752-4598. ; 6, s. 639-657
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to compare the butterfly assemblages in semi-natural pastures and power-line corridors and to analyse the effects of vegetation height, occurrence of trees and shrubs and different flowering vascular plant groups on butterfly diversity and abundance. Twelve of 26 analysed butterfly species were more abundant in power-line corridors than in semi-natural pastures. Only one species preferred semi-natural pastures. In semi-natural pastures butterflies were most common in segments with tall vegetation, whereas butterflies in power-line corridors were most common in segments with vegetation of short or intermediate height. Short vegetation was sparser in power-line corridors (mean cover 4%) than in semi-natural pastures (33%), whereas tall vegetation was more common in power-line corridors (59%) than in semi-natural pastures (35%). The amount of flowers was the factor that affected the abundance of most species. Twenty-one of the 26 species showed positive associations with numbers of flowers of different families. Flowers of the plant families Apiaceae, Caryophyllaceae, Primulaceae, Rubiaceae, Scrophulariaceae, and Violaceae showed positive associations with the abundance of several butterfly species. Vegetation height seems to be a limiting factor in semi-natural pastures, and less intensive management (division of pastures into grazing pens, late season grazing, grazing every second year, or reduced grazing pressure) would benefit butterflies. In power-line corridors (dominated by tall vegetation) the opposite would be beneficial for butterflies, for example more frequent clearing of vegetation along the power-line trails combined with mowing of selected areas.
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| 35. |
- Berg, Åke, et al.
(författare)
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Butterfly distribution and abundance is affected by variation in the Swedish forest-farmland landscape
- 2011
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Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207 .- 1873-2917. ; 144, s. 2819-2831
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Tidskriftsartikel (refereegranskat)abstract
- Remaining patches of semi-natural grasslands are hot spots for biodiversity in modern agricultural landscapes. In Sweden semi-natural pastures cover approximately 500,000 ha. However, power-line corridors, road verges and clear-cuts cover larger areas (in total about 2,000,000 ha), and these open, less intensively managed habitats are potentially important for species associated with taller vegetation and flower resources (e.g. pollinating insects). The aim of the present study was to evaluate the relative importance of semi-natural pastures and the other three open habitats for butterflies in 12 forest-farmland mosaic landscapes in south central Sweden. Species composition differed significantly between habitats in multivariate analyses. Power-line corridors and semi-natural pastures harbored several species that were disproportionally abundant in these habitats (13 and 8 species, respectively), and power-line corridors also harbored several species that were classified as typical in indicator species analyses. There were more butterfly species, higher abundances and a tendency for more individuals of red-listed species in power-line corridors than in the other three habitats. Effects of the surrounding landscape composition seemed to be weaker than that of the local habitat. However, species composition was significantly associated with landscape composition and species with intermediate and low mobility were more abundant in forested landscapes than in landscapes dominated by arable fields. Analyses of flying time and host plants for larvae suggest that early flying species and species associated with dwarf shrubs were more common in power-line corridors than in the other habitats. A landscape perspective, which takes several habitats into account, is needed for conservation of butterfly communities in forest-farmland landscapes. Power-line corridors and road verges offer possibilities for creating habitats that are suitable for pollinating insects through conservation-oriented management. (C) 2011 Elsevier Ltd. All rights reserved.
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| 36. |
- Berg, Åke
(författare)
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Conservation of birds in fragmented landscapes requires protected areas
- 2022
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Ingår i: Frontiers in Ecology and the Environment. - : Wiley. - 1540-9295 .- 1540-9309. ; 20, s. 361-369
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Tidskriftsartikel (refereegranskat)abstract
- For successful conservation of biodiversity, it is vital to know whether protected areas in increasingly fragmented landscapes effectively safeguard species. However, how large habitat fragments must be, and what level of protection is required to sustain species, remains poorly known. We compiled a global dataset on almost 2000 bird species in 741 forest fragments varying in size and protection status, and show that protection is associated with higher bird occurrence, especially for threatened species. Protection becomes increasingly effective with increasing size of forest fragments. For forest fragments >50 ha our results show that strict protection (International Union for Conservation of Nature [IUCN] categories I-IV) is strongly associated with higher bird occurrence, whereas fragments had to be at least 175 ha for moderate protection (IUCN categories V and VI) to have a positive effect. This meta-analysis quantifies the importance of fragment size, protection status, and their interaction for the conservation of bird species communities, and stresses that protection should not be limited to large pristine areas.
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| 37. |
- Berg, Åke
(författare)
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Density and reproductive success of Skylarks Alauda arvensis on organic farms - an experiment with unsown Sylark plots
- 2011
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Ingår i: Ornis Svecica. - 1102-6812. ; 21, s. 3-10
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Tidskriftsartikel (refereegranskat)abstract
- Skylark plots (unsown plots; 10–25 m2 per ha) in autumn cereal fields have had positive effects on Skylark density and reproductive success on conventional farms in Britain. We tested if the same effect could be found in organic farms in Sweden by comparing paired fields with and without unsown plots in similar settings. We found that the plots had no effect. Skylark density was only associated (negatively) with field size and not with occurrence of Skylark plots, vegetation structure, yield or weed harrowing. Number of clutches per territory was affected by yield (negative) and vegetation cover (positive) but not by Skylark plots. Number of fledglings per clutch showed negative association with yield and visibility through the sward. The amount of weed was larger near Skylark plots from the preceding year than in other parts of the field. The yield (and probably vegetation density) was lower on these fields than in conventional autumn sown fields, but still negative effects of the crop (yield levels) were found.
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| 38. |
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| 39. |
- Berg, Åke, et al.
(författare)
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Linking occurrence and changes in local abundance of farmland bird species to landscape composition and land-use changes
- 2015
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 204, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Changes in agricultural policies have caused dramatic changes in land-use in agricultural landscapes. To investigate whether such changes in land-use relate to temporal changes in bird communities a repeated inventory (1994 and 2004) of farmland birds was made in 212 point-count sites in south-central Sweden.Distinct changes in abundance of several species over the study period were recorded, abundance of the 16 studied species decreased by 23%. The decline was significant for eight species, while two species increased significantly. Persistence and colonisation models suggested similar species-habitat relationships as the snapshot models, i.e. eight of the 12 associations were in line with what could be expected from the snapshot models. Occurrence of nine species was linked to land-use whereas six species displayed links between changes in occurrence and changes in land-use. In line with previous studies positive effects of short rotation coppice and negative effects of autumn-sown crops were found, while set-asides showed fewer effects than expected. In the snapshot models several species showed links to landscape characteristics such as amount of forest (negative for five species) and landscape heterogeneity (positive for six species). The evidence for effects of the landscape variables on persistence/colonisation was more restricted.The results suggest that both land-use changes and the landscape setting may cause local changes in abundance of farmland birds, even for species displaying a general decline in numbers between years, the effects of land-use changes being, however, strongly species specific. (C) 2014 Elsevier B.V. All rights reserved.
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| 40. |
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| 41. |
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| 42. |
- Berg, Åke, et al.
(författare)
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Power-line corridors as source habitat for butterflies in forest landscapes
- 2016
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Ingår i: Biological Conservation. - : ELSEVIER SCI LTD. - 0006-3207 .- 1873-2917. ; 201, s. 320-326
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Tidskriftsartikel (refereegranskat)abstract
- Modern intensified agriculture has decreased farmland heterogeneity, which has led to strong negative effects on farmland biodiversity. However, partly forested landscapes seem to offer many alternative habitats for open habitat species such as butterflies, since modern forestry and development of infrastructure has created several new environments such as forest road verges and power-line corridors. The aim of the present study was to investigate the importance of power-line corridors (PLCs) as butterfly habitats by testing i) if species richness and abundance of butterflies in PLCs are affected by adjacent habitat composition (i.e. comparisons of PLCs with different adjacent habitats), ii) if PLCs act as source habitat through spill-over of individuals into adjacent forest roads and semi-natural pastures and iii) if species composition differs among the investigated habitat types. To investigate this we censured the butterfly fauna in 23 study landscapes in south-central Sweden. We found support for the hypothesis that PLCs may act as source habitats for butterflies in forest roads and pastures, since species richness and abundance were decreasing with increasing distance to PLC from 0 to 500 m. In addition, the species composition in forest roads and pastures close to and far from PLCs was similar, suggesting that this increase was not due to an increase of PLC specialists in the other two habitats. Thus, we have shown that PLCs in themselves are important butterfly habitats independently of adjacent habitat composition (adjacent mature forest, clear cuts or arable land), and they contribute to increased species richness and abundance of butterflies in surrounding areas over 10 times larger than their own width. (C) 2016 Elsevier Ltd. All rights reserved.
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| 43. |
- Berg, Åke
(författare)
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Standardiserad inventering av kornknarr (Crex crex) i Västmanlands och Uppsala län 2006-2007.
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Syftet med denna rapport är att visa vilken sorts habitat kornknarren föredrar att häcka i, och vilken skötsel som är mest gynnsam för arten. Slutsatserna som dras kan vara en hjälp i arbetet med att genomföra lämpliga åtgärder för arten, t.ex. senareläggning av skörd, så att kornknarren kan häcka ostört och så att populationen på sikt ökar i landet. Kornknarren förekommer på åkermark och ängsmark i södra delarna av landet och längs Norrlands kustland. Arten är talrikast på Öland, på Gotland, i Västra Götaland samt i Uppland och Västmanland. Arten har under 1900-talet minskat kraftigt i antal. Under 2006 och 2007 inventerades kornknarrar i 12 inventeringsområden, sju belägna i Uppland; Fyrisån, Bälinge mossar, Tegelsmora, Torstuna, Dannemora, Marma skjutfält och Alunda och fem belägna i Västmanland; Gnienområdet, Svartåområdet, Vibyslätten, Skultuna och Baggådalen. Totalt observerades 113 sjungande kornknarrar i de 12 undersökningsområdena (49 hanar 2006 och 64 hanar 2007). Det största antalet observerades på Marma skjutfält (7 resp. 25 revir), i Svartåområdet (14 resp. 8 revir) och Torstunaområdet (12 resp. 7 revir). Kornknarren föredrog platser med hög vegetation (medelvärde 60 cm), på platser med frisk till fuktig mark, ofta med förekomst av diken. Hög vegetation i lämpliga miljöer fanns på ohävdade strandängar, slåtterängar, vallar och fleråriga trädor. Vårsådd, höstsådd, kultiverad betesmark och ettårig träda hyste färre kornknarrar än vad som kunde förväntas. Kornknarrarna satt till stor del i olika revir de båda undersökningsåren. En relativt stor andel av reviren fanns i habitat som påverkas av slåtter och putsning (slåtterängar, vallar och fleråriga trädor). Till skillnad från många andra ängsmarksfåglar (t ex vadare) så undvek inte kornknarren skogskanter (många fanns inom 100m från kantzoner). 87 revir besöktes dagtid för att undersöka om kornknarrarna fanns kvar i reviren. Bandspelare användes för att locka kvarvarande hanar. I sex av reviren fanns kornknarrarna kvar och visade kraftiga reaktioner på uppspelning av band med ropande kornknarrar, vilket kan tas som ett tecken på att de fortfarande var aktiva i reviret och ”troligen häckade”. Strategier för att gynna kornknarren bör fokusera på att bibehålla ängsmarker med hög vegetation, genom slåtter med något eller några års mellanrum. Eftersom kornknarrarna inte återkommer till exakt samma revir år från år så är det svårt att i detalj peka ut olika revir som bör skötas extensivt för att gynna kornknarren, men områden där arten rapporteras regelbundet är de mest lämpliga. Större områden (>10ha) är att föredra eftersom kornknarren ofta förekommer i ”aggregationer”. På fleråriga trädor bör det vara rimligt att avstå från skötselåtgärder de år kornknarrar förekommer. På slåtterängar med miljöersättning bör slåttern kunna skjutas upp om kornknarrar förekommer, men ersättning för bortfall av produktion av foder skulle vara gynnsamt. Förslagsvis bör områden på 1-2 ha lämnas vid slåtter och om möjligt bör korridorer till angränsande områden med hög vegetation lämnas t ex längs diken och kantzoner.
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| 44. |
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| 45. |
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| 46. |
- Berg, Åke
(författare)
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Uncultivated Plants and Livelihood Support- a case study from the Chepang people of Nepal
- 2009
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Ingår i: Ethnobotany Research and Applications. - 1547-3465. ; 7, s. 409-422
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Tidskriftsartikel (refereegranskat)abstract
- This study documents the use of un-cultivated food plants, their status and contribution to the livelihoods of the Chepang people of Nepal. Diversity fairs, key informant interviews and household surveys were used to identify use of plants as food, medicine and for cultural reasons. the uses of 85 uncultivated plants ios documented
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| 47. |
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| 48. |
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| 49. |
- Bergman, Åke, et al.
(författare)
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Science and policy on endocrine disrupters must not be mixed : a reply to a "common sense" intervention by toxicology journal editors
- 2013
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Ingår i: Environmental Health. - : BioMed Central (BMC). - 1476-069X. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- The "common sense" intervention by toxicology journal editors regarding proposed European Union endocrine disrupter regulations ignores scientific evidence and well-established principles of chemical risk assessment. In this commentary, endocrine disrupter experts express their concerns about a recently published, and is in our considered opinion inaccurate and factually incorrect, editorial that has appeared in several journals in toxicology. Some of the shortcomings of the editorial are discussed in detail. We call for a better founded scientific debate which may help to overcome a polarisation of views detrimental to reaching a consensus about scientific foundations for endocrine disrupter regulation in the EU.
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| 50. |
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