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2553 Uppsatser om Forest land - Sida 27 av 171
Effekt av karbonatisering med biogas på aska från trädbränslen
It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.
Leder storskaliga landinvesteringar i jordbruk till hållbar utveckling? En fallstudie av projektet ProSavana i Moçambique
Large-scale land investments is not a new phenomenon, but increasing prices on food and agrofuels have inflated prices on land and has led to an enhanced interest in landinvestments from a range of different actors. The ProSavana project in the Nacala corridor in the Nampula province, northern Mozambique is a large-scale land investment with the purpose of establishing intensive commercial agriculture and is planned to be implemented this year (2013). The project is financed by Brazil and Japan in collaboration with the government of Mozambique. It is not quite clear how large-scale land investments affect the areas they are implemented in and how they can affect the possibilities for sustainable development in these areas. Both opportunities and problems can be observed within the social, economic and ecological dimensions of sustainable development.
Lägesbild : Problemområden vid skapandet
Within the framework of the concept of Network Based Defence (NBF) services should be available in the network, in order to increase the aggregate capacity. A common situation picture is one of these services.The aim of this paper is to answer the problem "What are the main problem areas in the creation of a situation picture in the land arena, with the help of the technical sensors that exist today?" and to develop a basis for continued research in the field situation in the concept Networking Enabled Command, Control and Collaboration (NEC3) at JCDEC (Joint Concept Development and Experimentation Centre). To answer the problem, a descriptive method is to be used in descriptions of the land arena, the information arena and the sensors and a deductive method is used when analyzing the asensors in the land arena.The problems that exist in the creation of a common situation picture, is that different types of obstacles makes it difficult for the sensors, the large number of people who are not combatants and that it is difficult to judge if a civilian vehicle is a threat, then it could be driven by civilians or by combatants..
Två nya trailerkoncept för transport av rundvirke hos Stora Enso : en analys av prestation och flexibilitet
The need for roundwood transport capacity vary throughout the year. The need during a period is influenced mainly by the volume transported the period, the number of days during which transport can be carried out, seasonal variations in road conditions and the weight of the roundwood, and the origin of the wood (private forest owners/ forest companies). The need for transport capacity generally increase during the winter and in spring, after thawing. Lack of logging trucks combined with a lack of drivers for these trucks make it hard to hire extra help during periods of increased transport capacity needs. It is also very expensive to keep logging trucks for use only during these periods.
In this thesis, two new concepts based on the partial transport by truck tractors have been examined, to find out the possibility for increased performance and flexibility.
Indelning av trakter inför gallring på Holmen Skog : en utvärdering av svårigheter och möjligheter
A common goal in practical forest management is to maximize the yield, measured in economical terms. When a forest stand is thinned a so called inoptimality loss can arise due to non-optimal decisions. This means that the selected management schedule results in a lower net present value than the optimal one which lowers the profitability for the forest owner. Holmen Skog uses the term tract which means an aggregation of stands made before a management action. A tract should be delineated in different tract parts in connection with pre-thinning planning if there is different bearing capacity within the tract, different thinning grades should be used or if the tract contains a weaker part that should not be thinned.
Trädslagsinverkan på markvegetationens utveckling i odlingsförsök med tall och contorta :
In the 1970?s it was predicted that in the beginning of the 21st century there would be a timber shortage in Sweden and a large scale introduction of the exotic tree species lodgepole pine started. An introduction of a foreign tree species means a risk of a negative influence on the forests ecosystem. Today, the stands that were established in the 70?s are middle-aged and the effect on the forest floor vegetation can be studied.
Stamräkning och identifiering av åtgärdsbehov i röjnings- och gallringbestånd med hjälp av låghöjdsbilder
This report is an assessment of the feasibility of using aerial photographs to estimate number of stems per hectare in young forest stands, used together with upper height to determine the need for pre-commercial thinning or ordinary thinning cutting. Aerial photo-interpretation was conducted in 2007 on assignment of Stora Enso Skog AB. A mean height function based on stand age produced with data from Bergvik Skog AB?s 2006 forest inventory assessment was used as a proxy for upper height and used together with photo-interpreted number of stems per hectare to determine the need for thinning cutting according to Bergvik Skog AB?s definitions. The test area is located north of Falun on Bergvik Skog AB?s land.Flight altitude was approximately 900 m above ground and the aerial photos were taken by L&L Flygbildteknik AB.
Viltets inverkan på vegetationsutvecklingen i en Sydsvensk skogsföryngring :
Herbivore impact on the Swedish forest has under a long time been a common subject of
debate. There are many different opinions depending on what direction the forest owner has with his/her forest. Populations of moose and roe deer have increased significantly in Sweden during the last decades. The purpose of this study is to get a full picture of the herbivore impact on the regeneration areas. The field work was done once a year for seven years (1999?2005).
Gropkeramiska lerfiguriner ? stumma ber?ttare om en gemensam v?rldsbild
An archaeological excavation that was made in 2016 of a Pitted Ware Culture settlement at Tr?s?ttra in the northern archipelago of Stockholm was very rich in artefacts and features. Especially unique was the over 300 fragments of clay figurines that were found. Never had so many been discovered at a neolithic place in Sweden. In Scandinavia it is only on the Finnish
islands of ?land that similar figurines have been found.
The aim of this study is to increase the understanding of the clay figurines of Tr?s?ttra and ?land through comparative studies.
Multikriterieanalys av potentiella konflikter vid markanvändningsplanering - Naturstenbrytning i Lysekils kommun
The purpose of the essay Multi criteria analysis of potential conflicts concerning land use planning - natural stone mining in Lysekil municipal is to study possibilities and limitations in GIS based multi criteria analysis as a tool for land use planning. How GIS based multi criteria analysis can be implemented to localize potential conflict areas between natural stone mining and other land use activities and what advantages and disadvantages the method holds are the main issues of this study. The essay studies these questions through a case study, concerning the geographical area of Lysekil municipal in western Sweden and problematizes the interest of natural stone mining in relation to other land use interests. A literature study was carried through, concerning multi criteria analysis and planning. After collecting and processing of data the multi criteria analysis could be implemented in the ArcGIS tool Weighted Sum.
Hassel (Corylus avellana) som indikator på markanvändningshistorik
Hazel (Corylus avellana L.) is a common feature of meadows and pastures where it can grow in large populations and become very old. Is it possible to use the size of hazel stools for age determination and is it possible to use the size distribution of a population to provide information about how the land has been used? Hazel populations on ground where the lake-water level had been lowered, has been studied to validate an already developed growth model of hazel clones. Different hazel populations, on wooded meadows affected by mowing or grazing or overgrown meadows, were studied to evaluate the method utilizing hazel as land use indicator. The growth model was used to compare the size distributions of hazel populations with historical periods, which has been important for changes in agriculture or demography.
Har antalet naturvärdesträd i Sverige förändrats mellan 1999-2009?
Forestry and forest products are vital components of the Swedish economy but the forest is also important for recreation, hunting, out-door life and conserving biodiversity. The Swedish Forest Act has two equally important objectives, production and environmental protection. Polytax is the Swedish Forest Agency´s inventory programme which monitors progress toward the two objectives in connection with regeneration fellings. It includes data on environmental protection measures taken in connection with regeneration fellings. 30 § of the Swedish Forestry Act and related regulations specify the demands for conserva-tion of nature.
Metod för användning av Geografiska Informations System vid långsiktig vägplanering : en studie genomförd på Sveaskogs marker i Norrbotten
The forest industry is one of the most important industry branches in Sweden. Since the demand of high precision wood deliveries has increased, the demand on a well constructed forest road net also has increased. A good road net gives the wood-supplier competition advantages and also increases its service level towards its customers, lumber-mills and pulp-mills. In some parts of Norrbotten, the road net is still insufficient and not yet built out enough, and that is why it is important to know how to act and where to improve the road net in these areas.
The purpose of this thesis was to create a work-model for long term road planning in areas with no road net or a not yet complete road net. The model has been created in an ArcGis environment, where a long chain of tools has been tied together with the program ?Model builder?.
"Anders Andersson hade eld i sin tjärdal" : en analys av Jonas Åströms dagböcker 1868-1891
"Anders Andersson had a fire in his tar-kiln ". Analysis of Jonas Åström 's peasant-diary 1868-1891
Peasant diaries are notes written by farmers, crofters and other people connected with small-scale agriculture. The notes give unique information about diverse aspects of rural life, for example, personal relationships and work, travel and regularity of church attendance. One such diary was written by Jonas Åström who lived in the county of Västerbotten, Sweden. The main aim of this study is to describe the work done by farmers in the 19th century, focusing on their use of forest resources, as recorded in his diary.
Landskapsplanering och konnektivitetsförbättringar inom värdetrakter i Västerbottens län :
According to the Swedish strategy for forest protection, additionally 40 000 ha productive forestland will be protected in the county of Västerbotten, between 1999 and 2010. A national project was carried out to distinguish the proportion of forest with a high biological value, in all counties. The project resulted in demarcation of small landscape areas or small ?biological value regions? (bvr), with higher concentrations of forests with conservation values and red listed species than the surroundings. In Västerbotten, 26 such bvr?s were identified and the Counties Agency and Forest Agency in Västerbotten developed a regional strategy for forest conservation to standardize the forest protection process.