13 research outputs found

    Luckhuggning och vedlevande skalbaggar i frivilliga avsättningar : trädslag och dödvedstypens inverkan på skalbaggarnas abundans och artrikedom

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    Coarse dead wood (CWD) and gaps are structures that have become sparse in Swedish forests as a result of forestry. This is believed to be one factor contributing to diminishing biodiversity. Because of political undertakings to preserve biodiversity, Swedish agencies and forestry companies now aim to restore these and other structures. To do so prescribed measures of nature conservation are today being practiced. One such measure is artificial gap creation. This study analyzes the effects of this measure on saproxylic beetle communities. The measure involve the cutting of several gaps per hectare and stand, as well as creating four CWD substrates in several gaps: Tipped trees, cut trees, girdled trees and high stumps. Data was collected from substrate traps as well as on substrate- and stand properties. In this study the effects that different substrate properties have on the abundance and species richness of the saproxylic beetle community were analyzed. GLMM-models were constructed for each of the two response variables, using several explanatory variables. Results indicate that abundance was most affected by the type of substrate, while species richness was most affected by its positive relationship to substrate diameter. The difference in abundance between substrate types could indicate that different species breed in different substrates. The positive effect that increased diameter have on species richness could be a result of how a larger substrate house larger communities of beetles – but since substrate diameter had no significant effect on abundance it could also indicate differences in inter-species substrate preferences.Grövre död ved (CWD) och gläntor är strukturer som minskat i svenska skogslandskap under det senaste århundradet och utvecklingen tros vara en bidragande faktor till Sveriges minskande biodiversitet. I enlighet med politiska åtaganden rörande bevarandet av biodiversitet vill nu myndigheter och skogsbolag återskapa dessa och andra strukturer genom särskilt tilltagna restaureringsåtgärder. En sådan åtgärd är artificiellt skapande av luckor i skogen, vilket även ämnar lokalt öka mängden CWD. Åtgärden innebar i detta försök att man högg upp ett antal luckor per hektar och bestånd, samtidigt som man skapade fyra slags substrat inom ett antal luckor: Tippade träd, kapade träd, ringbarkade träd samt högstubbar. Under följande år samlades fångstdata in från kläckfällor som monterats till ett urval av substraten. Därtill samlades även data in rörande bestånds- och substrategenskaper. I den här studien ville man analysera vilken effekt som olika substrategenskaper har på saproxyla skalbaggars artrikedom och abundans. GLMM-modeller konstruerades för de båda responsvariablerna och olika substrategenskaper användes som förklarande variabler. Studiens resultat visade bland annat att substrattypen hade en stor inverkan på abundansen, medan artrikedomen påverkades kraftigast av ett positivt förhållande till substratdiameter. Den kraftiga skillnaden i abundans mellan olika substrattyper kan antyda att olika arter förökar sig i olika substrat. Den positiva effekten av ökad substratdiameter på artrikedomen skulle kunna vara en följd av att ett större substrat kan husera större skalbaggesamhällen – men då ingen effekt av diameter kunde kopplas till den totala abundansen av skalbaggar skulle detta även kunna peka på olika substratpreferens mellan arter

    Hur påverkas markvegetationen i boreala skogsekosystem av produktionshöjande åtgärder?

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    I den boreala vegetationszonens skogar är kväve i regel en tillväxtbegränsande faktor som ofta har en avgörande effekt på markvegetationen. Markvegetationen har betydelse för biologiska processer, biodiversitet och ger ekosystemtjänster. Kväve tillkommer dessa ekosystem genom atmosfärisk kvävedeposition, kvävefixering och skogsgödsling. I och med krav på ökad produktion kan skogsgödsling bli en allt vanligare åtgärd inom skogsbruket vilket skulle öka kvävemängderna i skogen. Vi undersökte därför vilken effekt detta skulle kunna ha på en medelgod tallskogs markvegetation. Vår studie baserades på data från Skogforsks gödslingsförsök 165, Hagfors. Gödslingsbehandlingarna pågick med olika intervall och doser från 1981 till 2003. Sex arters täckningsgrader, uppmätta och skattade under sex år från och med avverkningen 2006 samlades in och tilldelades oss. Utvecklingen på försöksytorna jämfördes med utvecklingen på obehandlade kontrollytor. Med dessa data analyserade vi effekten av de två gödslingsbehandlingarna på markvegetationens utveckling efter avverkningen. Analyserna säkerställde inte att kvävegödslingarna hade en effekt på markvegetationens utveckling. Däremot säkerställdes en återkommande tidsmässig effekt på markvegetationens utveckling på både de gödslingsbehandlade ytorna och kontrollytorna. Detta tolkade vi som en kraftig hyggeseffekt som överskuggade eventuell effekt av gödslingsbehandlingarna. Försökets gödslingsbehandlingar var mångdubbelt kraftigare än dagens rekommenderade skogsgödslingar och atmosfäriska kvävedeposition. Därför kan detta resultat tolkas som att dagens skogsgödslingsåtgärder och kvävedeposition inte har någon nämnvärd effekt på markvegetationens utveckling efter avverkningar, jämfört med hyggeseffekten. Därmed inte sagt att skogsgödsling saknar effekt på markvegetationen, bara att denna studie inte kunde visa på den. För att testa generaliteten i studiens resultat krävs fler försöksstudier på ståndorter med varierande produktivitet.In forests of the boreal vegetation region, nitrogen is commonly a growth limiting factor and of great importance to the forest floor vegetation. The forest floor vegetation is essential to biological processes, biodiversity and providing ecosystem services. Nitrogen enters these ecosystems through atmospheric deposition, nitrogen fixation and forest fertilization. As the demand for forest production is increased, the more common fertilization might be which ought to alter the forest’s nitrogen supply. Therefore we wanted to examine the effects that modified nitrogen levels would have on forest floor vegetation of a common, medium rich pine forest. Our study was based on data of the Skogforsk experiment 165, Hagfors. The nitrogen fertilization treatments were conducted with different intervals and intensities on the site from 1981 until 2003. The data collected and assigned to us, was the cover data of six different species, measured and estimated during six consecutive years from clear cutting in 2006. The vegetation development on fertilized plots was compared to that of control plots. With these data we analyzed the effects of fertilization on the development of forest floor vegetation after the clear-cut. Statistical analysis could not determine whether nitrogen fertilization affected the development of forest floor vegetation. But a reoccurring effect on the development of forest floor vegetation is that of time, both on fertilized and untreated plots. This was interpreted as the effect of clear-cutting, overriding possible effects of fertilization. The intensities of these fertilization treatments were much higher than the sum of recommended forest fertilization and nitrogen deposition. Therefore we do not expect forest fertilization and atmospheric deposition to affect forest floor vegetation development after clear-cuttings, compared to the clear-cut effects. Though this does not mean that forest fertilization has no effect at all, just that this study could not detect it. To test the generality of these results additional experimental studies are needed and in stands of varying productivity

    One Year of In-Flight Results from the Prisma Formation Flying Demonstration Mission

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    The Prisma smallsat in-orbit test-bed was launched on the 15th of June, 2010 to demonstrate strategies and technologies for formation flying and rendezvous. The mission consists of two spacecraft: Mango and Tango. Mango is 3-axis stabilized and is equipped with a propulsion system providing full 3D orbit control capability. Tango has a simplified solar magnetic control system and does not have any orbit control capability. The two spacecraft were launched clamped together into a 720/780 km altitude sun synchronous dawn-dusk orbit, and later separated in August of 2010. Since then, the two spacecraft, and rather lean operations team, have been performing a steady march through a tight mission and experiment timeline. This paper gives an overview of the Prisma mission in general and will focus on the lessons that have been learned from running a relatively intense, yet lean, small satellite technology demonstration mission. It has proven to show the value of autonomy and small platform applications, allowing for a high return on effort. Spacecraft autonomy and small, highly competent teams have allowed for quick and cost effective adaptations to changes and problem situations. The broad range of flight results from only one year in operation support these conclusions

    Fem uppsatser om Gogol's Kappan

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    Subclinical Inflammation with Increased Neutrophil Activity in Healthy Twin Siblings Reflect Environmental Influence in the Pathogenesis of Inflammatory Bowel Disease

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    Background: The mechanisms behind increased fecal calprotectin (FC) in healthy relatives of patients with inflammatory bowel disease (IBD) are unknown. Our aims were to explore if there is a subclinical inflammation with increased neutrophil activity in healthy twin siblings in discordant twin pairs with IBD and to assess the influence of genetics in this context. Methods: Nuclear factor kappa B (NF-B) and neutrophil activity, based on myeloperoxidase (MPO) and FC, were analyzed in healthy twin siblings in discordant twin pairs with IBD and compared with healthy controls. NF-B and MPO were assessed by immunohistochemistry and FC by enzyme-linked immunosorbent assay. Results: In total, 33 of 34 healthy twin siblings were histologically normal. Increased NF-B was more often observed in healthy twin siblings in discordant twin pairs with Crohn's disease (13/18 [73%]) and with ulcerative colitis (12/16 [75%]) than in healthy controls (8/45 [18%]). MPO was more often increased in healthy twin siblings in discordant pairs with Crohn's disease (12/18 [67%]) than in healthy controls (11/45 [24%]) and FC more often in healthy twin siblings in discordant pairs with ulcerative colitis (14/21 [67%]) than in healthy controls (6/31 [19%]). Interestingly, the observed differences remained when healthy monozygotic and dizygotic twin siblings were analyzed separately. Conclusions:We observed increased NF-B, MPO, and FC in healthy twins in both monozygotic and dizygotic discordant pairs with IBD. These novel findings speak for an ongoing subclinical inflammation with increased neutrophil activity in healthy first-degree relatives.Funding Agencies:Bengt Ihre's foundation  Nanna Svartz' foundation  Orebro University Hospital Research Foundation  Orebro County Research Foundation  Swedish Foundation for Gastrointestinal research</p

    Concordance in anti-OmpC and anti-I2 indicate the influence of genetic predisposition : results of a European study of twins with Crohn's disease

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    An adaptive immunological response to microbial antigens has been observed in Crohn's disease (CD). Intriguingly, this serological response precedes the diagnosis in some patients and has also been observed in healthy relatives. We aimed to determine whether genetic factors are implicated in this response in a CD twin cohort. In total, 82 twin pairs (Leuven n = 13, Maastricht n = 8, A-rebro n = 61) took part: 81 pairs with CD (concordant monozygotic n = 16, discordant monozygotic n = 22, concordant dizygotic n = 3, discordant dizygotic n = 40) and 1 monozygotic pair with both CD and ulcerative colitis. Serology for Pseudomonas fluorescens-related protein (anti-I2), Escherichia coli outer membrane porin C (anti-OmpC), CBir1flagellin (anti-CBir1) and antibodies to oligomannan (anti-Saccharomyces cerevisiae antibody [ASCA]) was determined by standardized enzyme-linked immunoassay. All markers were more often present in CD twins than in their healthy twin siblings. Using the intraclass correlation coefficient (ICC), agreements in concentrations of anti-OmpC and anti-I2 were observed in discordant monozygotic but not in discordant dizygotic twin pairs with CD (anti-OmpC, ICC 0.80 and -0.02, respectively) and (anti-I2, ICC 0.56 and 0.05, respectively). In contrast, no agreements were found in anti-CBir, immunoglobulin (Ig) G ASCA and ASCA IgA. We show that anti-I2 and anti-CBir1 statuses have specificity for CD and confirm previous reported specificities for anti-OmpC and ASCA. Based on quantitative analyses and observed ICCs, genetics seems to predispose to the anti-OmpC and anti-I2 response but less to ASCA and anti-CBir1 responses
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