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Showing 171 to 180 of 212 (0.034 seconds)Spelling suggestions: "subject:"botanik"" "subject:"botaniky""
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What is the potential to increase local biodiversity in semi-urban amenity grasslands through meadow constructions?Östberg, Alexandra January 2022 (has links)
The loss of biodiversity worldwide and methods of prevention are hot subjects receiving increased interest in todays’ research. Meadow construction in urban areas has been the focus of recent studies to increase both local and global biodiversity. In my report, I address potential analyses to conduct in advance before practical meadow constructions in a landscape. The subject I chose to focus on for this report was a LONA-project aimed to construct meadows on contemporary amenity grasslands in a semi-urban municipality. I used vegetation data from an inventory executed in 2021. Patches were in advance classified based on conditions observed during the inventory with class 1 obtaining the highest meadow potential, class 2 obtaining mediocre potential, and class 3 weak or no potential. I analysed vegetation data on species richness, environmental indicator values, and composition. Additionally, I analysed the soil types and historical land uses in the study area to display credible soil characteristics. The order of Lepidoptera was used as a model taxon for pollinators and the red-listed Marsh fritillary (Euphydryas aurinia) was separately analysed for conservational purposes. To illustrate the landscapes’ ability to facilitate the dispersal of butterflies, connectivity analyses of varying meadow construction scenarios were executed. Results indicate higher species richness on average per patch and more indicator species in class 1, suggesting a better starting point and making quality assessments more credible in comparison to class 2. Underlaying soil type seems to some extent to influence the meadow potential by affecting vegetation composition and hence butterfly occurrence in terms of host plant distribution. I could however not draw any conclusions from the effect of historical land use on current patch classifications, and consequently meadow potential. To facilitate for E. aurinia to widen its distribution in the study area, and to avoid local extinction, further conservational efforts should focus on mimicking the conditions and current management of the powerline corridor, that currently yields high diversity of butterflies and abundance of E. aurinia, to other powerline corridors in the study area. To facilitate dispersal of butterflies and other pollinators, target meadow areas of both class 1 and class 2 patches should be constructed to avoid patch isolation, as illustrated in the connectivity analyses. Further research is needed to investigate other factors possibly affecting suitability of grasslands for meadow construction.
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Tillväxt och etablering efter nyplantering av ålgräs (Zostera marina) i HallandRathsman, Jens, Ljung, Angelica January 2023 (has links)
Ålgräs fungerar som ekosystemingenjörer som förser både människan och naturen med en mängd viktiga ekosystemtjänster och tillhandahåller olika ekosystemfunktioner. Ålgräsängens vegetation skapar en fysisk struktur till den annars kala, mjuka ler- eller sandbottnen och ökar den biologiska mångfalden. En annan viktig funktion som ålgräsängar skapar är habitat som fungerar som barnkammare för olika fiskarter, såsom torsk, flundror och sej. Det uppskattas att cirka 30% av de kända arealerna av ålgräsängar har försvunnit globalt och att 7% försvinner årligen. I Sverige kan liknande historiska förluster av ålgräs visas, bara i Bohuslän har 60% försvunnit sedan 1980-talet och ålgräsängarna fortsätter att minska till följd av fortsatt exploatering av kustområden. I detta projekt har vi undersökt ålgräsets förmåga till etablering samt dess tillväxt efter förflyttning och omplantering i ett nytt habitat vid Hallands kust. Plantering av ålgräs har inte tidigare gjorts i Halland och syftet med denna studie var att se om plantering var möjligt och hur stor tillväxt det sker på blad samt antal nya tillväxande vegetativa skott.Våra resultat visade att det fanns signifikanta skillnader för ålgräsets överlevnad mellan de tre olika metoder som vi utförde vid plantering. Vår metod singelskottsmetoden visade sig vara mest lyckad vid platsen, som låg på ett område med relativt hög våg- och vindexponering, vilket vi anser är typiskt för den Halländska kusten. De andra två metoderna, nätmetoden samt grillspettsmetoden, som användes inkluderade förankring av plantorna vilket resulterade i sämre överlevnad. Detta kan ha berott på att det fanns flera stressfaktorer vid platsen som vågor, vind och algpåväxt och att förankring störde ålgräsets etablering. / Eelgrass act as ecosystem engineers, providing both humans and nature with a variety of important ecosystem services and providing various ecosystem functions. The vegetation that eelgrass beds provide is a physical structure to the otherwise bare, soft clay or sand seabed and increases biodiversity. Another important function that eelgrass beds provide is that they create habitats that act as nurseries for various fish species, such as cod, flounder and pollock. It is estimated that around 30% of the known areas of eelgrass meadows have disappeared globally and that 7% is decreasing annually. In Sweden, similar historical losses of eelgrass can be seen, only in Bohuslän, 60% has disappeared since the 1980s and continues to decrease as a result of continued exploitation of coastal areas. In this project, we have investigated the ability of eelgrass to establish as well as its growth after relocation and replanting in a new habitat on the coast of Halland. Planting of eelgrass has not previously been done in Halland, so the purpose of this study was to see if this was possible and how much growth occurs on leaves and the amount of new growing vegetative shoots. Our results showed that there were significant differences in the survival of the eelgrass between the three different methods we used when planting. Our method the single-shoot method proved to be most successful at the site, which was in an area with relatively high wave and wind exposure, which we believe is typical for the coast of Halland. The other two methods used, the netmethod and skewermethod, included anchoring the plants which resulted in poorer survival. This may have been because there were several stress factors at the site such as waves, wind and algae growth and that anchoring disturbed the establishment of the eelgrass.
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Aspekte der plastidären Transkription / der Einfluss des Phytohormons Cytokinin und in vivo-Analysen zur Regulation des rpoB-OperonsHertel, Stefanie 13 August 2009 (has links)
In dieser Arbeit wurde die plastidäre Genexpression hinsichtlich zweier Aspekte untersucht: der Cytokinineinfluss auf die plastidäre Transkription und ihrer Komponenten sowie eine in vivo-Charakterisierung von PrpoB-345, des Promotors des rpoB-Operons im Tabak. Cytokinine beeinflussen die Chloroplastenbiogenese und –funktion. Um den Einfluss von Cytokinin auf die plastidäre Genexpression zu untersuchen, wurden run-on-Transkriptionsassays und quantitative real-time RT-PCR von BA-behandelten seneszenten Tabakblättern und sieben-Tage-alten Arabidopsis- und Tabakpflanzen durchgeführt. Zeitreihenanalysen zeigten eine Aktivierung der plastidären Transkription in jungen Pflanzen und im seneszenten Tabak 2 h bzw. 3 h nach BA-Applikation. Abgeschnittene Blätter von Tabakmutanten mit konstitutiv reduziertem Cytokiningehalt antworteten bereits nach 30 min der Hormonbehandlung. Es gibt jedoch keinen eindeutigen Hinweis für eine direkte Korrelation zwischen der Expression der nukleär kodierten Phagentyp-RNA-Polymerasen und der BA-induzierten transkriptionellen Aktivierung der Plastidengene. Zusammengefasst, scheint die Antwort auf exogenes Cytokinin vom physiologischen Status der Chloroplasten, die von der Pflanzenart sowie vom endogenen Cytokiningehalt beeinflusst werden, abzuhängen. Plastidäre Gene höherer Pflanzen werden von mindestens zwei RNA-Polymerasen transkribiert: die plastidär kodierte RNA-Polymerase vom Bakterientyp (PEP) und die kernkodierte Phagentyp-RNA-Polymerase (NEP). NEP transkribiert das rpoB-Operon, das drei von vier Untereinheiten der PEP kodiert. Transkriptions- und Transkriptanalysen von rpoB-Promotor-Deletionsmutanten ergaben Hinweise auf mögliche Regulationsstellen der Kontrolle der rpoB-Transkription. Neben PrpoB-345 konnten zwei weitere Promotoren kartiert werden. Einer von ihnen ist ein putativer PEP-Promotor, der auf autoregulatorische Rückkopplungsmechanismen bei der PEP-Expression hindeutet. / In this study, plastid gene expression was analyzed focusing on two aspects: the effect of cytokinin on plastid gene transcription and its components, and the in vivo characterization of PrpoB-345, the promoter of the rpoB operon in tobacco. Cytokinins are involved in the control of chloroplast biogenesis and function. To study cytokinin effects on plastid gene expression, chloroplast run-on transcription and quantitative real-time RT-PCR from senescent tobacco leaves as well as Arabidopsis and tobacco seedlings after BA treatment were performed. Analyses of time series revealed that BA-induced changes in plastid gene expression are seemingly under circadian and homeostatic control. After 2 h and 3 h of incubation with cytokinin, a stimulation of chloroplast transcription could be observed in seedlings and senescent leaves, respectively. Detached leaves of tobacco mutants with reduced endogenous cytokinin content responded even faster to BA (30 min). There is no indication of direct correlation of the expression of nuclear-encoded plastid phage-type RNA-polymerases and the BA-induced transcriptional activation of plastid genes. In summary, the responsiveness to exogenous cytokinin depends on the physiological status of chloroplasts influenced by plant species and endogenous cytokinin pool. Plastid genes of higher plants are transcribed by at least two RNA polymerases: the plastid-encoded eubacterial-type RNA polymerase (PEP) and the nucleus-encoded phage-type RNA polymerase (NEP). NEP transcribes the rpoB operon encoding three of four subunits of PEP. Transcription and transcript analyses from rpoB promoter deletion mutants indicated putative regulatory sites of control of rpoB transcription which may also interact with (cytokinin-regulated) specificity factors. Beside PrpoB-345, two additional rpoB promoters could be mapped. One of them is a putative PEP promoter which may imply autoregulatory loops of PEP expression.
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Physiologische Untersuchungen am Stamm und im Kronenraum eines Fichtenaltbestandes nach experimenteller Manipulation des Wasser- und Ionenhaushaltes (Dachprojekt Solling) / Physiological investigations at the stem and in the crown of a Norway spruce stand after experimental manipulation of the water and ion-budget (roof project Solling)Meyer, Ann-Carolin 01 June 2001 (has links)
No description available.
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Pollinator communities and plant-pollinator interactions in fragmented calcareous grasslands / Bestäubergemeinschaften und Pflanze-Bestäuber-Interaktionen auf fragmentierten KalkmagerrasenMeyer, Birgit 19 July 2007 (has links)
No description available.
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Mekanisk uppgrävning: ett effektivt verktyg mot den invasiva främmande arten gul skunkkalla (Lysichiton americanus) : En utredning av behandlingsmetoderKekäle, Oscar January 2023 (has links)
Den biologiska mångfalden minskar globalt och ett av de största hoten utgörs av invasiva främmande arter. Natura-2000 området Fylleån, Halland, huserar en av de största svenska populationerna av gul skunkkalla (Lysichiton americanus). Arten utgör ett hot mot de naturvärden som finns i Fylleån och är subjekt för extensiva behandlingsarbeten i området för att motarbeta växtens effekt på ekosystemet. Det finns i dagsläget ingen evidens för att behandlingsmetoderna som presenteras av Naturvårdsverket och Havs- och vattenmyndighetens metodkatalog har effektivitet i svenska vattendrag. Målet med min studie är att undersöka effektiviteten av mekanisk uppgrävning samt ytlig hetvattensbehandling som behandlingsmetoder för gul skunkkalla. Jag undersöker även lämpligheten för användandet av övriga metoder presenterade av metodkatalogen och metoderna hetvattensbehandling och fröställningsborttagning som inte listats i metodkatalogen men som testas av myndigheter i viss utsträckning. Den första delen av studien genomförs som jämförelsestudie mellan områden som behandlats i olika grad med mekanisk grävning och hetvattenbehandling för att bestämma metodernas effektivitet. Den andra delen av min studie var att genom en litteraturgenomgång med metodkatalogen som utgångspunkt avgöra lämpligheten på och reflektera över metoderna samt reflektera över metodernas lämplighet att användas civilt. Min slutsats är att mekanisk grävning ger minskande populationer och signifikanta skillnader i individantal, förutsatt att behandlingen utförs rätt och konsekvent. Jag resonerar att andra behandlingsmetoder kan påverka mer organismer än vad man avsett och att de därför är olämpliga att bruka i Fylleån. Jag diskuterar vad jag anser är rimligt idéellt arbete i nuläget samt framtida potential och behovet av information i rätt kanaler. / Biodiversity is decreasing globally and one of the biggest threats is invasive alien species. The Natura-2000 area Fylleån, Halland, houses one of the largest Swedish populations of the American skunk cabbage (Lysichiton americanus). The species poses a threat to the natural values found in Fylleån and is subjected to extensive treatment to counteract the plant's effect on the ecosystem. There is currently no evidence for the effectiveness of the treatment methods presented by Naturvårdsverket and Havs- och vattenmyndighetens method catalog in Swedish watercourses. The goal of my study is to investigate the effectiveness of mechanical excavation and superficial hot water treatment as treatment methods for American skunk cabbage, along with hot water treatment and seed stand removal which are not listed in the method catalog but are tested by authorities to a certain extent. Through a comparative study between areas treated to varying degrees with mechanical digging and hot water treatment, I determine the effectiveness of the methods. The second part of my study was to try to determine the suitability of and reflect on the methods, as well as reflect on the suitability of the methods for civilian use through a literature review using the method catalog as a starting point. My conclusion is that mechanical digging produces declining populations and significant differences in found individuals, provided the treatment is carried out correctly and consistently. I reason that other treatment methods can affect more organisms than intended, and that they are therefore unsuitable for use in Fylleån.
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Biochemische und zellbiologische Charakterisierung des COP Vesikel vermittelten Proteintransports in PflanzenPimpl, Peter 03 May 2001 (has links)
No description available.
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Analyse des Transkriptionsfaktors TGA2.1 aus Nicotiana tabacum / Analysis of the transcription factor TGA2.1 from Nicotiana tabacumKegler, Carsten 26 June 2001 (has links)
No description available.
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Charakterisierung der konservierten Domänen des Transkriptionsfaktors N.t.BZI-1 / Characterisation of the conserved domains of transcriptionfactor N.t.BZI-1Kuhlmann, Markus 25 April 2002 (has links)
No description available.
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Molecular phylogeny and morphological reconstructions of Plagiochilaceae (Jungermanniopsida) with hypotheses on biogeography and divergence times / Verwandtschaftliche Untersuchungen und Merkmalsrekonstruktionen der Familie Plagiochilaceae (Lebermoose) mit Hypothesen zur Biogeographie und DivergenzzeitenGroth, Henk 03 November 2005 (has links)
No description available.
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