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In this diploma work influence of needle age at Rubisco activity and content in Norway spruce (Picea abies) was studied. The plants were cultivated in conditions with ambient (A) CO2 concentration (350 µmol CO2/mol) and elevated (E) CO2 concentration (700 µmol CO2/mol). Sampling was done two times during the growing season (in the middle of June and in the end of September) were taken. Initial and total Rubisco activities were measured spectrophotometrically. Rubisco content was determined by SDS–PAGE method. Rubisco activity in 18-months-old needles was in E higher than in A. Rubisco contents in current-year needles and one-year-old needles were in A higher than in E in September. These differences were statistically significant that demonstrates the down-regulation of Rubisco content in conditions of elevated CO2 concentration. It seems the course of activities and content depending on age of the needles are antiparallel, that means that decrease of content is followed by increase of activity.

In the current environment of severe climate change, studying the adaptability of Norway spruce to the environment, that is, local adaptation is of great significance for helping to protect forest tree species and genetic breeding. As a structural variation, copy number variations (CNVs) have been proved to play an important role in shaping population structure and local adaptation in marine species, going beyond traditional studies focusing only on SNPs. Therefore, this experiment was to investigate the association of genotypes, including CNVs and SNPs, with local adaptation in Norway spruce. About 5.631% of CNVs were screened from SNPs, and the population structure of Norway spruce was detected based on the data of SNPs and CNVs. Then, the associations between genotypes (SNPs and CNVs) and the environmental variables are calculated by the model, considering the effects of population structure. Finally, the relationship between CNVs and SNPs and local adaptation of Norway spruce was investigated by redundancy analysis (RDA). The results preliminarily revealed that SNPs and CNVs had certain effects on the local adaptation of Norway spruce and a significant correlation with various environmental factors. However, the results indicated comparing to SNPs, CNVs had no significant effect on the local adaptation of Norway spruce.

With the use of a process-orientated ecosystem model andmeasurements conducted at different Swedish coniferous forestsites, abiotic and biotic interactions between tree and soilwere identified and related to governing factors. Two differentmodelling approaches to describe soil temperatures at two sitesincluding hydrological transects were tested (I). The approachin which both canopy and soil were considered proved to be amore flexible tool to describe soil temperatures, especiallyduring snow-free winter periods. Five sites along a climatetransect covering Sweden were used to describe soil carbon poolchanges during an 80-year period simulation (II). The dynamicmodelling approach, with a feedback between abiotic and bioticsub-models, was successful in describing simplified patterns offorest stand dynamics and furthermore in differentiatingbetween climate and nitrogen availability factors. The largereffect of nitrogen availability compared to climate on soilcarbon pool changes was clearly shown. Keywords:SPAC; soil surface energy balance; Norwayspruce; canopy; LAI; climate; nitrogen; CoupModel

Nanocellulose is a sustainable material and has shown interesting properties in various applications. One such application is Pickering emulsion, where the nanocellulose stabilizes the oil and water interface. Thus, this project aimed to evaluate a new type of nanocellulose, cellulose oxalate (COX), derived from different sources, dissolving pulp and bark, as a potential emulsifier. The properties of the nanocellulose, such as the chemical composition, morphology, aspect ratio, viscosity, and surface tension, are analyzed to determine how it affects the Pickering emulsion. Pectin has reported having emulsifying properties. Therefore, pectin derived from the bark was also studied as a potential emulsifier.  The emulsion capacity and emulsion stability of the Pickering emulsion were estimated. Additionally, the emulsions were observed and visualized in an optical microscope, and it showed that all Pickering emulsions were successful. The COX and pectin particles were successfully adsorbed at the interface to form individual droplets which were stable enough not to coalescence. With the images from AFM, the aspect ratio and morphology of the particles were measured. COX pulp had an average width of 5.5 nm and an average length of 372 nm. COX bark had an average width of 3.9 nm and an average length of 257 nm. Notably, COX pulp does have a slightly higher aspect ratio than COX bark. DLS was another way the particle size was measured. However, it was not a suitable technique because both COX did indicate a relatively polydisperse system and are therefore not suitable to be measured by DLS. Furthermore, the viscosity of the COX pulp and COX bark suspensions were measured with an Ubbelohde capillary viscometer which was not an ideal method because the COX suspensions were too thick and gel-like for the instrument and got clogged constantly. As expected, the surface tension decreased steadily, more so for COX pulp than COX bark with increasing concentration. Then again, this means that COX has a hydrophobic property that does reduce the surface tension of water. Lastly, the carbohydrate analysis did indicate that both COX do have a high amount of glucose. Moreover, both COX did also show a significant amount of other components.  Overall, this study does conclude that COX pulp, COX bark, and pectin did stabilize the Pickering emulsion to some degree, despite being inconsistent and can therefore be considered effective emulsifiers. / Nanocellulosa är ett hållbart material som har visat intressanta egenskaper i olika applikationer. En specifik applikation är Pickering emulsion, där nanocellulosan stabiliserar gränsytan mellan olje-och vatten fasen. Därav var syftet med detta projekt att utvärdera en ny typ av nanocellulosa, cellulosaoxalat (COX) producerad från olika källor såsom förhandlad pappersmassa och bark som ett potentiellt emulgeringsmedel. De olika egenskaperna hos nanocellulosan dvs. den kemiska sammansättningen, morfologin, partikelstorlek, viskositet och ytspänning undersöktes för att bestämma hur de påverkar Pickering emulsionen. Pektin har också rapporterats att ha emulgerande egenskaper. Därför studerades även pektin producerad från bark som ett potentiellt emulgeringsmedel.  Emulsionskapaciteten och emulsionsstabiliteten hos Pickering emulsionen uppskattades. Dessutom observerades och visualiserades emulsionerna i ett optiskt mikroskop som visade att alla Pickering emulsioner var successiva. Det innebär att COX- och pektinpartiklarna adsorberades successivt vid gränsytan för att bilda individuella droppar som var stabila nog att inte koalescensera. Med hjälp av bilderna från AFM mättes storleken på partiklarna och dess morfologi bestämdes. COX-massa hade en genomsnittlig bredd på 5,5 nm en medellängd på 372 nm. COX-bark hade en genomsnittlig bredd på 3,9 nm och en medellängd på 257 nm. Från resultatet, kan det noteras att COX-massa har något större partikelstorlek är COX-bark. DLS var ett annat sätt att mäta partikelstorleken. Dock, var det inte en lämplig teknik eftersom både COX-massa och COX-bark visade ett relativt polydisperst system och är därav inte lämplig att mättas i DLS. Vidare så mättes viskositeten för COX-massa och COX-bark med en Ubbelohde kapillärviskometer, vilket inte heller var en idealisk metod att mäta med eftersom COX lösningen var för tjock och gel-liknande och täppte till instrumentet. Däremot, som förväntad minskades ytspänningen stadigt med ökande koncentration. Detta var mer tydligt hos COX- massa än COX-bark. Oavsett så betyder det att COX har en hydrofob egenskap som minskar ytspänningen hos vatten. Sist men inte minst så indikerade kemiska sammansättningsanalysen att båda COX har en stor mängd glukos. De har även en betydande mängd av andra komponenter.  Sammantaget drar denna studie slutsatsen att COX-massa, COX-bark och pektin stabiliserade Pickering emulsionen till en viss del relativt väl, trots att det var inkonsekvent så anses de vara effektiva emulsionsmedel.

Increased anthropogenic deposition of nitrogen (N) and land-use changes associated with planted forests have important implications for sustainable forest management and associated water quality. The purpose of the research for this dissertation was to explore how N deposition will affect the long-term health, productivity, and carbon (C) and N sequestration of conifer and hardwood forest types by examining the mechanisms controlling N cycling and NO3-N production in two watersheds with contrasting vegetation at the Fernow Experimental Forest (FEF), West Virginia. I utilized watershed C and N budgets to account for differences in stream export of NO3-N from streams draining adjacent watersheds containing (i) planted Norway spruce (Picea abies) and (ii) native Appalachian hardwoods. I also investigated spatial and temporal patterns of dissolved C and N across both watersheds and identified key soil properties associated with NO3-N in soil solution and streamwater. In a third study, I performed a soil inoculation and incubation experiment, which utilized soil from both watersheds, mixed in ratios in order to create a gradient of soil chemical and biotic characteristics. Important differences in biogeochemical cycling of C and N were documented in the watersheds after nearly 40 years of influence by contrasting vegetation. Total C and N pools were 28% and 35% lower in the spruce watershed than the hardwood watershed, respectively. Results also identify vegetation-mediated differences in soil characteristics, with lower soil pH and base cations, and higher extractable aluminum and C:N ratios measured in the spruce soil as compared to the native hardwood soil. Establishment of a spruce monoculture at the FEF significantly altered N cycling, depleted N stores, increased soil acidity, and altered organic matter dynamics, thus leading to low net nitrification rates. Carbon and N properties and processes in the soil profile should be taken into consideration in forests managed for ecosystem services including C sequestration and improvement or maintenance of water quality through alleviation of N inputs into aquatic ecosystems. / Ph. D.

The usage of biofuel as well as wood fuel has increased in Sweden and all of Europe during recent decades, and there are several reasons to believe that this increase will continue. An important reason for this increase is that the environmental and climate problems caused by fossil fuels are becoming even more evident. By replacing fossil fuel with biofuel, the problem of emissions from, among others carbon dioxide and sulphur compounds can be alleviated. However, substitution requires in many cases high quality processed biofuel. An early stage in the processing of biofuel is drying. Previous work treats the possibility of drying wood fuel in an efficient and environmentally sustainable manner. This thesis studies the bed drying technique, conducted both experimentally and through modeling of the drying process. The experimental work is based on continuous temperature measurements in the fuel bed and provides characteristics of the drying zone that develops in the bed during drying. The character of the drying zone is affected by both the qualities of the fuel and the operating parameters, and is decisive regarding the possibility of making the drying more efficient, i.e. optimize the usage of energy and produce a fuel with low and homogeneous moisture content. A mathematical simulation model has been developed to increase the understanding of bed drying. The model is based on fundamental physical principles and is made up of five differential equations that describe vapor flow, air flow, the fuel’s moisture content, and the bed’s pressure and temperature. The modeling work complements the experimental work and a simulation of the temperature distribution, pressure and the drying zone’s dispersion is in agreement with the experimental result. The drying of wood can signify an environmental and human health risk, since volatile organic compounds (VOC) are emitted during drying. The thesis studies these emissions with regards to type and quantity. The measurements show that the majority of the emitted compounds from Norway spruce and Scots pine are volatile monoterpenes, but also that other compounds are emitted, especially higher terpenes. Further, major differences between how the compounds are emitted and the quantities of the emitted compounds from heartwood and sapwood are shown. There are also large differences between types of wood, i.e. spruce and pine. It can be stated that both emission rate and total amount of emitted compounds increase with an increase in temperature. To reduce VOC emissions, the drying temperature should be maintained low. To develop an efficient bed drying process for wood biofuels, additional parameters must be analyzed further and weighed against each other. Based on the experimental method and the simulation model presented here, the drying can be optimized towards a more efficient use of thermal energy and a low and even moisture content in the dried biofuel.

Detta arbeta har utförts för att undersöka hur höstplantering av täckrotsodlad gran (Picea abies) och tall (Pinus sylvestris) överlever och utvecklas jämfört med vårplanterad. Detta i ett led för att se om man kan utöka planteringssäsongen för att få en jämnare arbetsbelastning över säsongen både i plantskolorna och ute i fält. Man har undersökt hur en planteringstidpunkt på sensommaren och hösten påverkar granplantors överlevnad jämfört med plantering på våren. Studien är utförd som en survey studie i södra Sverige på täckrotsplantor av gran som planterats på medelboniteter 2007-2009 och inventerats 2010. Höst och vårplanterade granplantor är jämförda parvis med samma planttyp, ålder, proveniens och geografiskt område. Följande saker har jämförts; plantor per hektar, höjdtillväxt, toppskottstillväxt, rothalsdiametern, frostskador, viltskador samt snytbaggeskador. Höstplantering av täckrotsodlad gran (Picea abies) ger ett lika bra resultat som vårplantering vad gäller överlevnad hos plantor. Höjdtillväxt och diametertillväxt blev något bättre på de höstplanterade plantorna jämfört med vårplanterade efterföljande vår. Höstplanterade plantor skadades något mer av frost än de vårplanterade gjorde, speciellt första säsongen. Vårplanterade plantor fick något mer viltskador än höstplanterade vilket kan bero på färre frostskador. Vårplanterade plantor skadades något mer av snytbagge än de höstplanterade. Snytbaggeskadorna var störst på de torra jordarna i östra området. Höstplantering av täckrotsodlad tall (Pinus sylvestris) gav ett lika bra resultat när det gäller överlevande plantor som gran. / This work has been performed in order to investigate if Norway spruce (Picea abies) and pine (Pinus sylvestris) container-grown seedlings planted in autumn gives the same quality as planting in spring in terms of surviving plants. This is in part to see if one can extend the planting season to get a more even workload over the season, both in nurseries and in the field. The study is designed as a survey study in Southern Sweden on container-grown seedlings of Norway spruce and pine planted 2007-2009 and inventoried 2010. The following things have been compared; plants per hectare, height growth, leading shoot growth, stem diameter, frost damage, damage by wild animals and pine weevil damage. Planting of Norway spruce (Picea abies) container-grown seedlings in autumn gives the same quality as planting in spring in terms of surviving plants. Height growth and diameter growth were slightly better the following season for seedlings planted in autumn compared to seedlings planted in spring. Seedlings planted in autumn were damaged by frost more than seedlings planted the spring, especially the first season. Seedlings planted in spring were slightly more damaged by wild animals than seedlings planted in autumn which may be because of less frost damage. Seedlings planted in spring were slightly a little more damaged by pine weevil than seedlings planted in autumn. Pine weevil damage was greatest in the arid soils in the eastern area. Container-grown seedlings of pine (Pinus sylvestris) planted in autumn gave equally good results as seedlings planted of Norway spruce.

The effect of steady shear stress on somatic embryos were investigated in a flow chamber and evaluated at different time intervals using microscopy technique. The development of meristematic cell clusters, i.e. the immature embryos, into a polarized somatic embryo, and the effect on the localization of the suspensor cells that form during development of the immature embryos, were studied as a function of shear stresses. With the distribution and growth rate of the meristematic and suspensor cells, the effect of stress on the embryo development was established. Furthermore, the effect of shear stress on the cells at molecular level, the reaction of integrin-like proteins, the production of reactive oxygen species and the pore size of the cell walls involved in the shear stress responses, were investigated with molecular techniques. In general, shear stress inhibits meristematic cells growth. Meristematic cells grow fastest at shear rate of 86 s-1 among all the tested shear stress conditions. By combining the results of meristematic cells growth and suspensor cells formation, it suggests that there is a critical shear rate between 86 and 140 s-1, at which no suspensor cells form. The unidirectional flow with different shear stresses helps the polarized growth and the unidirectional alignment of suspensor cells. Reactive oxygen species and integrin-like protein are detected in the stressed cells as cellular responses to shear stresses. By monitoring the pore size and uptake time of cells to macromolecules with solute-exclusive experiments, it suggests that the stressed cells expedite the response to plasmolyzing components that are used to induce maturation treatment thus affect the response to maturation stimuli.

Denna studie beskriver effekterna beträffande överlevnad och tillväxt hos gran (Picea abeis L. Karst) vid tillsats av superabsorbent Luquasorb 1280R i samband med plantering under olika betingelser. Plantor i form av täckrot och barrot studerades. Tillsats av superabsorbent visade sig ha en positiv inverkan på de studerade parametrarna i jämförelse med referensmaterial utan tillsats av superabsorbent. Detta visade sig särskilt vid extremförsök under tak utan tillgång till vattentillförsel under försöksperioden, förutom vattentillsats i samband med plantering. / This study describes the effects concerning survival and growth of Norway spruce seedelings (Picea abeis L. Karst) by addition of superabsorbent Luquasorb 1280R in connection with planting under differnt conditions. Container seedlings and bare-root seedlings were studied. The addition of superabsorbent showed a positive influence regarding the studied parameters in comparision with reference material without the addition of superabsorbent. This was most obvious at the the extreme test under roof without access to additional water during the test period, except water added in connection with planting.