Bioethanol is one alternative energy fuel that can be produced from different types of biomass. Second generation bioethanol comes from fermentation of lignocellulosic material and can be seen as a more environmental friendly alternative as e.g. forest residues and agricultural by-products are used. To be able to use lignocellulosic biomass in ethanol production, it has to be subjected to different treatments first. In this study, Aspen sawdust was used as lignocellulosic material.

Hybrid aspen is a crossbreed between European and North American aspen. It is a fast growing tree species that has shown strong growth in the South of Sweden. The follow-ups that have been made on hybrid aspen stands, have mainly been done on plant material in the South of Sweden. In the North of Sweden, only occasional studies have been made, and the knowledge of Northern hybrid aspen stands is, thus, unsatisfactory.In the South of Norrland, land owners have planted hybrid aspen, but what kind of plants it is, and how well these stands have established, is not ascertained, since data has not been compiled on the subject.The objective of this study is to evaluate practical plantations of hybrid aspen in the South of Norrland regarding height growth, survival and damages. The ambition is to increase the knowledge about practical plantations regarding height growth, survival and damages, and from the conclusions thereof, give recommendations for future establishments of hybrid aspen in the area.For the study, eight hybrid aspen stands in the South of Norrland were localised.

This report concerns the for Sweden foreign tree species hybrid larch, hybrid aspen and poplar, and focuses on the area Kalmar and Mönsterås municipalities. The report shows that there are not only advantages with these species. The larch, the most common of the alien tree species has the greatest problems due to that its timber is difficult to sell in the area but also the Larch´s poor pulp quality and is more likely to be damaged by wildlife than the spruce is. Hybrid Aspen is much easier to sell and is used like regular aspen for match wood and textile pulp. Its disadvantage is the high cost for plants and to prevent damage from wildlife.

Aspen (Populus tremula) is a tree that is important for biodiversity. It is a pioneer tree that is favored by much light. It is possible that aspens that regenerated on agricultural land have a different importance for biodiversity than aspens that regenerated in forests, since their conditions have been different. By studying how the land use have changed you can see how many of today?s aspens regeneretad on agricultural land.

Pine twisting rust (Melampsora pinitorqua) is a parasitic rust fungus found all across Sweden causing damage resulting in lower quality and reduced tree growth in pine stands. In Sweden, the fungus is dependent on two alternate hosts; European aspen (Populus tremula) and Scots pine (Pinus sylvestris). Pine twisting rust has five different spore stages, two of them (uredinio- and teliospores) on the leaves of aspen. Injures on aspen caused by pine twisting rust is not extensive. On the other hand, when it infects the annual shoots of Scots pine it often results in a bent steam or even a top shoot breakage.

As demand for renewable energy is increasing rapidly, the market for biomass pellets is expected to continue to grow in the near future. Most of the new raw materials that are discussed for pellet production have one thing in common; the production costs will increase compared to using traditional raw materials such as sawdust and planer shavings. The aim of this thesis is to investigate to what degree increased use of new raw materials for pellet production will affect the general pellet prices in Sweden and to survey what plans Swedish pellet producers have concerning new raw materials. To investigate the raw material situation of the Swedish pellet producers an industry survey was performed. Literature studies were also made on previous research in the subject field. Calculations of the production costs for pellets were done for the raw materials sawdust, wet sawmill chips and energy wood respectively. New raw materials are already used by the large-scale pellet producers in Sweden.

Wood pellets are an upgraded product of residuals from several wood processing industries, for example saw mills and pulp industries. The pellets are produced by pressing the milled and dried sawdust to cylindrical units with a higher density than the initial raw material. Pellets have great benefits compared to the raw material: high energy per volume, good transport and storage properties and homogeneity. Several parameters collaborate in the whole process, which makes it complex. Wood is a heterogeneous material, chemically and structurally dependent on wood parts, habitat and storage procedures.

Aspen (Populus tremula L.) and goat willow (Salix caprea L.) are two important tree species in the aspect of nature conservation. Due to the elimination of forest fires, a former negative attitude towards deciduous trees in forestry and a strong herbivore pressure, these tree species have been negatively affected during the last fifty years. The aim of this study was to investigate whether the occurrence of aspen and goat willow could be related to either human impact or to site properties, such as ground moisture and vegetation type. A side study included an inventory of a number of cyanobacterial tree lichens on aspen and goat willow in order to try to relate the occurrence of these lichens species to stand history and stand properties. The study was performed in Hamra State Forest in northern Dalarna. Nature reserves were compared with stands in managed areas.

Aggression between laboratory mice is a common problem and can result in welfare issues such as mice hurting or killing each other and also stress. Swedish laws and regulations clearly states that mice must be housed with a companion due to their natural social structure. Many studies have investigated the effect off enrichment, group size, cage size and other potential changes in in their environment on the occurrence of aggression. Even with these changes aggression can exist and therefore a new solution was tested in this paper. The proposed solution was to house an intact mouse with a castrated one and thus fulfill laws and regulations while still maintaining the physiology of one of the mice for the purpose of medical experiments.

Peat litter is a soft material with high absorbency. About hundred years ago many farmers in Sweden used peat litter to their dairy cows. After the World War II the use of peat litter decreased and the farmers used more straw. Nowadays (year 2007), when it is harder to find straw and sawdust to buy, peat litter is advancing again. The purpose with this study is to investigate peat as a litter to dairy cows.

This project is a collaboration with Ett Klick för Skogen, a foundation that buys and preserves endangered forests in Sweden. There are several ways of helping the foundation, e.g. buy a tree and for this the buyer obtains a symbolic diploma. Many organisations uses this method to collect money and for me the lack of a thorough expressions are consistent. The objective with this project has been to renew these diplomas for Ett Klick för Skogen and in the long run increase the collections and preservation of endangered forests in Sweden.The idea has been to vivify hardwood trees in a new and rather poetic than pedagogic manner.

This project is a collaboration with Ett Klick för Skogen, a foundation that buys and preserves endangered forests in Sweden. There are several ways of helping the foundation, e.g. buy a tree and for this the buyer obtains a symbolic diploma. Many organisations uses this method to collect money and for me the lack of a thorough expressions are consistent. The objective with this project has been to renew these diplomas for Ett Klick för Skogen and in the long run increase the collections and preservation of endangered forests in Sweden.The idea has been to vivify hardwood trees in a new and rather poetic than pedagogic manner.

The understanding of the role of nature for rehabilitation of both physical and psychological afflictions has greatly increased in the last few years. There?s a lot of science that describes the healing effects of nature. The rehabilitation garden in Alnarp has contributed with very positive results from the treatments of patients with burnout syndrome. In the first stages of rehabilitation, the need for calm is very important and a demand-less and stress-free environment is of essence.

Hårdgörning av trä syftar till att göra materialet hårdare. Detta går att åstadkomma genom komprimering, det komprimerade materialet tenderar dock att återgå mot sin ursprungsform då materialet utsätts för fukt om ingen låsning sker. Låsningen kan ske mekaniskt i en treskiktskonstruktion som motverkar träets fuktrörelser. Dessa skivor har dock visat sig vara instabila och tidigare försök har uppvisat deformationer i form av kupning. Denna undersökning syftar till att utreda förutsättningarna för att använda komprimerad asp samt att ta fram underlag för framtagning av en kommersiell produkt.Praktiska tester har genomförts för att studera hårdhet, återfjädring och densitet hos det komprimerade virket.

Allt eftersom behovet att finna nya energikällor som ersättning för fossila bränslen växer, ser etanol ut att vara en av lösningarna på detta. Etanol kan användas i många applikationer där vi idag använder fossila bränslen. Etanol har många fördelar, den bidrar inte till den globala uppvärmningen, den kan produceras lokalt och kan inom en snar framtid bli ekonomiskt förmånlig genom skatteregleringar och minskade produktionskostnader. Utvecklingen av etanolproducerande fabriker blir mer sofistikerad och producerar mer etanol på mindre råvara. För att ytterligare öka effektiviteten på en fullskalig anläggning måste restprodukterna bli utnyttjade på ett ekonomiskt, miljömässigt och effektivt sätt. Aspen Plus har används för att simulera olika tekniska lösningar och driftfall. Förbränning av restprodukter för att producera ånga till etanolprocessen och kraftvärmeanläggning har studerats. Ekonomisk studie av en investering i en kraftvärmeanläggning och olika tillvägagångssätt för att torka bränslet har blivit utredda..