16 research outputs found

    Tree Cover Mapping Based on Sentinel-2 Images Demonstrate High Thematic Accuracy in Europe

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    The spatial and temporal distribution of trees has a large impact on human health and the environment through contributions to important climate mechanisms as well as commercial, recreational and social activities in society. A range of tree mapping methodologies has been presented in the literature, but tree cover estimates still differ widely between the individual datasets, and comparisons of the thematic accuracy of the resulting tree maps are rather scarce. The Copernicus Sentinel-2 satellites, which were launched in 2015 and 2017, have a combination of high spatial and temporal resolution. Given that this is a new satellite, a substantial amount of research on development of tree mapping algorithms as well as accuracy assessment of said algorithms have to be done in the years to come. To contribute to this process, a tree map produced through unsupervised classification was created for six Sentinel-2 tiles. The agreement between the tree map and the corresponding national forest inventory, as a function of the band combination chosen, was analysed and the thematic accuracy was assessed for two out of the six tiles. The results show that the highest agreement between the present tree map and the national forest inventory was found for bands 2, 3, 6 and 12. The present tree map has a relative difference in tree cover between 8% and 79% compared to previous estimates, but results are characterised by large scatter. Lastly, it is shown that the overall thematic accuracy of the present map is up to 90%, with the user’s accuracy ranging from 34.85 % to 92.10 %, and the producer’s accuracy ranging from 23.80 % to 97.60 % for the various thematic classes. This demonstrates that tree maps with high thematic accuracy can be produced from Sentinel-2. In the future the thematic accuracy can be increased even more through the use of temporal averaging in the mapping procedure, which will enable an accurate estimate of the European tree cover

    Is genetic diversity more important for terpene emissions than latitudinal adaptation? : Using genetically identical trees to better understand emission fluctuations across a European gradient

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    Biogenic volatile organic compounds (BVOCs) are trace gases other than CO2 and CH4 produced and emitted by the vegetation. The group consists of thousands of compounds in various shapes and sizes and with short atmospheric lifetimes. Some of the most common BVOC groups are called isoprene, monoterpenes and sesquiterpenes. For the plant, the emission of BVOCs is used for plant communication, attracting pollinators, to deter herbivores and to enhance abiotic stress defense against for example high temperatures, irradiation or oxidative stresses. But once released into the atmosphere, they are affecting the atmospheric chemistry which in effect alters our climate. Depending on the atmospheric composition, BVOC emissions can either enhance tropospheric ozone and indirectly prolong the lifetimes of greenhouse gases such as methane by reducing the concentration of hydroxyl radicals, or increase the formation of aerosols and cloud condensation nuclei which may mitigate the effect of greenhouse gases on global warming.It is fairly well known that BVOCs have an impact on the climate. However, whether the BVOC emissions have a warming or cooling effect on the overall climate is difficult to determine due to existing emission pattern variations both between individuals of the same species and between species. Some of the reasons which are often discussed to be influential and where there is relatively little data available are within-species genetic variation, stress response, adaptation to different weather and climatic conditions and seasonality. In this thesis, focus has been given to the importance of genetic diversity and adaptation to different growing conditions. Studies have been conducted on three European tree species with genetically identical individuals across a latitudinal gradient, stretching from Slovenia to southern Finland. The main results were that even though the emission amounts varied between sites due to differences in weather events, the progression of the growing season and insect outbreaks, the compound composition between individuals were similar both across latitudes and between measurement years. By showing compound composition stability for genetically identical trees, the results highlights the importance of taking genetic diversity into account in terms of observed emission pattern variations. The response to changing light conditions on the emission amount of different compounds was also investigated. The results uncovered that different compounds had different emission responses to changing light conditions, but that the response of the compounds were fairly similar across different species

    Metanutsläpp från det smältande Arktis

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    Populärvetenskaplig sammanfattning I Arktis finns det enorma lager av kol som ligger i och under permafrosten, vilket är frusen mark som inte har tinat på två år. Mycket tyder på att delar av dessa lager är känsliga för en temperaturökning och idag sker en pågående uppvärmning. Arktis värms snabbare än övriga jorden på grund av att vit reflekterande is och snö smälter, vilket resulterar i att hav och land kan absorbera mer av den inkommande solinstrålningen. Värmetransport till Arktis från resten av jorden ökar, det förutspås leda till temperaturökningar på upp till 8°C så snart som till år 2050. Om permafrosten smälter kommer delar av det lagrade kolet att frigöras som koldioxid och metan. Eftersom metan är en effektiv växthusgas, skulle det kunna leda till en kraftig förstärkning av växthuseffekten. Idag är metanutsläppen från Arktis relativt små i jämförelse med antropogena utsläpp, men Arktiska utsläpp har potential att överskugga dessa. Detta arbete syftar till att beskriva dagens metanutsläpp och utreda vilka återkopplingseffekter en temperaturökning kan få på de framtida metanutsläppen från Arktis. Idag släpper Arktis ut mellan 31 och 45 Mt (miljoner ton) metan per år enligt de senaste modellerna baserade på satellitmätningar. På land finns det 320 000 Mt kol lagrat i permafrosten, vilket bedöms kunna frigöras som metan vid en uppvärmning och smältning av permafrosten. Till havs är det osäkert hur mycket metan som kan komma ut vid en uppvärmning, men potentiellt lika mycket som på land. På land är de viktigaste effekterna av temperaturökningen att mer upptinat kol från permafrosten exponeras för nedbrytning och vars hastighet stiger med temperaturen. Till havs finns det ett grunt område där gas fångad under permafrosten på havsbottnen har börjat tränga upp. Utsläppen från detta område har potential att bli mycket kraftiga. Uppgifterna om framtidens metanutsläpp från Arktis skiljer sig mycket åt, från en ökning på bara 10 Mt metan per år fram till år 2050 till en ökning som skulle få mängden metan i atmosfären att tredubblas till år 2100. Denna rapport finner det troligt att utsläppen av metan från Arktis kommer att öka kraftigt i framtiden.The permafrost area in the Arctic region contains vast carbon stocks within and beneath the permafrost, which is frozen ground that has not thawed in two years. These carbon stocks are sensitive to ongoing global warming. When the white and reflective snow and ice melts, the remaining land and sea surfaces absorb more shortwave radiation and get warmer. Heat transport to the Arctic will also increase and temperatures are predicted to rise up to 8°C until 2050. If the permafrost melts, the stored carbon might be released as methane and carbon dioxide. Since methane is a potent greenhouse gas, it would mean a potential increase of the greenhouse effect. The current methane emissions from the Arctic are relatively small in comparison to anthropogenic methane emissions, but the Arctic emissions have the potential to surpass them in future. This study aims to describe today’s methane emissions from the Arctic and to investigate which future feedback mechanisms on permafrost thawing a temperature rise might trigger. Today’s methane emission from the Arctic is according to the latest models based on satellite measurements between 31-45 Mt (million tons). Carbon stocks in terrestrial permafrost areas that could be released as methane if thawed contain 320 000 Mt of carbon. The stocks levels beneath the sea are more uncertain, but could potentially release as large emissions of methane as from land. The most important effects of a temperature increase on land are that more carbon is made available from thawing permafrost and decomposition is increasing with rising temperature. At sea, there is a shallow layer where gas is trapped under the that might release substantial amounts of methane if the permafrost layer was melting. These emissions can potentially increase the atmospheric concentration of methane substantially. The prediction of future methane releases from the Arctic varies dramatically, from small increases of only 10 Mt methane until 2050 to an increase that would triple the amount of methane until 2100. This report finds it likely that methane emissions might rise substantially in the future

    Elderly people's participation in drug therapy : A Qualitative Study

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    Bakgrund: Det naturliga åldrandet och intag av många läkemedel medför en ökad risk för läkemedelsbiverkningar. För att äldre personer ska känna sig trygga med sin läkemedelsbe-handling är det viktigt att få tillräckligt med information. Delaktighet är en förutsättning för partnerskapet i personcentrerad vård vilket innebär att vårdpersonal och patient ska dela på information, samtal och beslutsfattande.Syfte: Syftet med studien var att beskriva äldre personers upplevelser av delaktighet i läke-medelsbehandling.Metod: För studien valdes kvalitativ design. Semistrukturerade intervjuer genomfördes med 16 deltagare som var i åldrarna 75-94 år, 12 av deltagarna var kvinnor och 4 män. Samtliga av deltagarna bodde i eget boende. Insamlad data analyserades med hjälp av manifest och latent innehållsanalys enligt Graneheim och Lundman.Resultat: Efter analys av innehållet framkom ett tema, delaktighet – en balans mellan auto-nomi och kunskap, och fyra underliggande kategorier, att vara nöjd med sin läkemedelsbe-handling, att sträva efter mer kunskap, att vara en del i beslutsfattandet samt upplevelsen av delaktighet utifrån vårdpersonalens stöd och information.Slutsats: De äldre beskriver olika behov av att vara delaktiga i sin egen läkemedelsbehand-ling och därför bör alla patienter få möjligheten att välja graden av delaktighet. För att upp-fylla detta är det viktigt att personcentrerad vård tillämpas av vårdpersonal för att vården ska kunna anpassas efter individens behov.Background: Natural aging and consumption of many drugs increases the risk of drug side effects. For older people to feel safe with their medication, it is important for them to get suf-ficient information. Participation is a precondition for partnership in person-centered care, which means that health professionals and patients have to share information, discussion and decision making.Aim: The aim of the study was to describe older people's experiences of participation in the drug therapy.Method: Qualitative design was chosen for the study. Semi-structured interviews were con-ducted with 16 participants who were aged 75-94 years, 12 of the participants were women and 4 were men. All of the participants lived in their own homes. Collected data were ana-lyzed using manifest and latent content analysis according to Granheim and Lundman.Result: After content analysis a theme appear: participation - a balance between autonomi and knowledge. Four underlying categories were identified: to be satisfied with their drug therapy, to strive for more knowledge, to be part of decision-making and the experience of participation on the basis of health care personnel support and information.Conclusion: The elderly describe different needs to be involved in their own drug therapy, and all patients should therefore have the opportunity to choose their degree of participation. To fulfill this objective, it is important that person-centered care is applied by medical profes-sionals so that care can be adapted to individual needs

    Elderly people's participation in drug therapy : A Qualitative Study

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    Bakgrund: Det naturliga åldrandet och intag av många läkemedel medför en ökad risk för läkemedelsbiverkningar. För att äldre personer ska känna sig trygga med sin läkemedelsbe-handling är det viktigt att få tillräckligt med information. Delaktighet är en förutsättning för partnerskapet i personcentrerad vård vilket innebär att vårdpersonal och patient ska dela på information, samtal och beslutsfattande.Syfte: Syftet med studien var att beskriva äldre personers upplevelser av delaktighet i läke-medelsbehandling.Metod: För studien valdes kvalitativ design. Semistrukturerade intervjuer genomfördes med 16 deltagare som var i åldrarna 75-94 år, 12 av deltagarna var kvinnor och 4 män. Samtliga av deltagarna bodde i eget boende. Insamlad data analyserades med hjälp av manifest och latent innehållsanalys enligt Graneheim och Lundman.Resultat: Efter analys av innehållet framkom ett tema, delaktighet – en balans mellan auto-nomi och kunskap, och fyra underliggande kategorier, att vara nöjd med sin läkemedelsbe-handling, att sträva efter mer kunskap, att vara en del i beslutsfattandet samt upplevelsen av delaktighet utifrån vårdpersonalens stöd och information.Slutsats: De äldre beskriver olika behov av att vara delaktiga i sin egen läkemedelsbehand-ling och därför bör alla patienter få möjligheten att välja graden av delaktighet. För att upp-fylla detta är det viktigt att personcentrerad vård tillämpas av vårdpersonal för att vården ska kunna anpassas efter individens behov.Background: Natural aging and consumption of many drugs increases the risk of drug side effects. For older people to feel safe with their medication, it is important for them to get suf-ficient information. Participation is a precondition for partnership in person-centered care, which means that health professionals and patients have to share information, discussion and decision making.Aim: The aim of the study was to describe older people's experiences of participation in the drug therapy.Method: Qualitative design was chosen for the study. Semi-structured interviews were con-ducted with 16 participants who were aged 75-94 years, 12 of the participants were women and 4 were men. All of the participants lived in their own homes. Collected data were ana-lyzed using manifest and latent content analysis according to Granheim and Lundman.Result: After content analysis a theme appear: participation - a balance between autonomi and knowledge. Four underlying categories were identified: to be satisfied with their drug therapy, to strive for more knowledge, to be part of decision-making and the experience of participation on the basis of health care personnel support and information.Conclusion: The elderly describe different needs to be involved in their own drug therapy, and all patients should therefore have the opportunity to choose their degree of participation. To fulfill this objective, it is important that person-centered care is applied by medical profes-sionals so that care can be adapted to individual needs

    Women's choice to achieve better psychological well-being after mastectomy

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    För många kvinnor kan det vara en förlust att förlora det ena eller båda brösten. Detta kan leda till att kvinnornas upple-velse av den kvinnliga identitet förändras vilket även påver-kar kvinnornas psykiska välbefinnande. Kvinnors psykiska behov blir inte alltid tillgodosedda i hälso- och sjukvården. Syftet med studien var att belysa vad som påverkar kvinnor att uppnå ökat psykiskt välbefinnande efter mastektomi. En litteraturstudie genomfördes där 14 vetenskapliga artiklar bearbetades utifrån studiens syfte. Resultatet visade på att kvinnornas känsla av normalitet, helhet och kvinnlig identitet var känslor som kvinnorna ville uppnå genom sina val av bröstrekonstruktion eller användning av bröstprotes. I kvin-nornas beslutfattningsprocess framkom det att stöd från när-stående och sjuksköterska, delaktighet i behandling och in-formation var viktiga komponenter för att kvinnorna skulle uppnå högre psykiskt välbefinnande efter mastektomin. Det framkom i flera studier att kvinnor hade velat få mer infor-mation och träffa kvinnor som genomgått bröstrekonstruk-tion för att få råd och stöd. Det är viktigt som sjuksköterska att vara medveten om kvinnornas behov av stöd och att kun-na ge adekvat information som leder till att kvinnorna kan vara delaktiga i sin behandling och ta autonoma beslut. Mer forskning om protesanvändning behövs då det inte fanns mycket tillgängligt

    BVOC emissions from English oak (<i>Quercus robur</i>) and European beech (<i>Fagus sylvatica</i>) along a latitudinal gradient

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    English oak (Quercus robur) and European beech (Fagus sylvatica) are amongst the most common tree species growing in Europe, influencing the annual biogenic volatile organic compound (BVOC) budget in this region. Studies have shown great variability in the emissions from these tree species, originating from both genetic variability and differences in climatic conditions between study sites. In this study, we examine the emission patterns for English oak and European beech in genetically identical individuals and the potential variation within and between sites. Leaf scale BVOC emissions, net assimilation rates and stomatal conductance were measured at the International Phenological Garden sites of Ljubljana (Slovenia), Grafrath (Germany) and Taastrup (Denmark). Sampling was conducted during three campaigns between May and July 2014. Our results show that English oak mainly emitted isoprene whilst European beech released monoterpenes. The relative contribution of the most emitted compounds from the two species remained stable across latitudes. The contribution of isoprene for English oak from Grafrath and Taastrup ranged between 92 and 97 % of the total BVOC emissions, whilst sabinene and limonene for European beech ranged from 30.5 to 40.5 and 9 to 15 % respectively for all three sites. The relative contribution of isoprene for English oak at Ljubljana was lower (78 %) in comparison to the other sites, most likely caused by frost damage in early spring. The variability in total leaf-level emission rates from the same site was small, whereas there were greater differences between sites. These differences were probably caused by short-term weather events and plant stress. A difference in age did not seem to affect the emission patterns for the selected trees. This study highlights the significance of within-genotypic variation of BVOC emission capacities for English oak and European beech, the influence of climatic variables such as temperature and light on emission intensities and the potential stability in relative compound contribution across a latitudinal gradient

    Isoprenoid emission response to changing light conditions of English oak, European beech and Norway spruce

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    Light is an important environmental factor controlling biogenic volatile organic compound (BVOC) emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 ?molm2 s-1), whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds -pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds -pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or temperature dependencies for individual compounds across species. Light is an important environmental factor controlling biogenic volatile organic compound (BVOC) emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 ?molm-2 s-1), whilst other chamber conditions such as temperature, humidity and CO2 levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds -pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds -pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or temperature dependencies for individual compounds across species. Light is an important environmental factor controlling biogenic volatile organic compound (BVOC) emissions, but in natural conditions its impact is hard to separate from other influential factors such as temperature. We studied the light response of foliar BVOC emissions, photosynthesis and stomatal conductance on three common European tree species, namely English oak (Quercus robur), European beech (Fagus sylvatica) and two provenances of Norway spruce (Picea abies) in Taastrup, Denmark. Leaf scale measurements were performed on the lowest positioned branches of the tree in July 2015. Light intensity was increased in four steps (0, 500, 1000 and 1500 ?molm-2, s-1), whilst other chamber conditions such as temperature, humidity and CO2, levels were fixed. Whereas the emission rate differed between individuals of the same species, the relative contributions of compounds to the total isoprenoid emission remained similar. Whilst some compounds were species specific, the compounds -pinene, camphene, 3-carene, limonene and eucalyptol were emitted by all of the measured tree species. Some compounds, like isoprene and sabinene, showed an increasing emission response with increasing light intensity, whereas other compounds, like camphene, had no significant emission response to light for most of the measured trees. English oak and European beech showed high light-dependent emission fractions from isoprene and sabinene, but other emitted compounds were light independent. For the two provenances of Norway spruce, the compounds -pinene, 3-carene and eucalyptol showed high light-dependent fractions for many of the measured trees. This study highlights differences between compound emissions in their response to a change in light and a possible light independence for certain compounds, which might be valid for a wider range of tree species. This information could be of importance when improving emission models and to further emphasize the discussion regarding light or temperature dependencies for individual compounds across species

    Isoprenoid emission variation of Norway spruce across a European latitudinal transect

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    Norway spruce (Picea abies) is one of the dominant tree species in the European boreal zone with the capacity to grow over large areas within Europe. It is an important emitter of biogenic volatile organic compounds (BVOCs), which can act as precursors of photochemical smog and ozone and contribute to the formation and growth of secondary organic aerosols (SOA) in the atmosphere.Isoprenoid emissions were measured from Norway spruce trees at seven different sites, distributed from Ljubljana in Slovenia to Piikkiö in Finland. Four of the sites were part of a network of genetically identical spruce trees and contained two separate provenances. The remaining three sites were part of other networks which have been used to conduct studies in the European boreal zone.There were minimal differences in the standardized emission rates between sites and across latitudes. The emission profile differed between provenances and sites, but there were not any distinct patterns which could be connected to a change in latitude. By using genetically identical trees and comparing the emission rates between sites and with genetically different trees, it was observed that the emission patterns were mostly influenced by genetics. But in order to confirm this possible stability of the relative emission profile based on genetics, more studies need to be performed.The effects of branch height, season and variation between years on observed emission pattern variations were also investigated. There were indications of potential influences of all three factors. However, due to different experimental setups between measurement campaigns, it is difficult to draw any robust conclusions
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