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455 Uppsatser om Basiphilous pine forests - Sida 14 av 31

Samband mellan virulensgener och VTEC-infektioner : Riskklassificeringssystem för VTEC

To curb greenhouse gases and mitigate climate change is one of the biggest challenges human society face today. Carbon dioxide (CO2) has accumulated rapidly in the atmosphere as a consequence of burning of fossil fuels and deforestation. The aim of this study is to explore two methods to store carbon dioxide in geological formations and biological sinks. The aim is also to discuss the two mitigation options from a sustainable perspective and whether it can lead to a better environment and benefits for local and global societies. The research questions are: Which method to store carbon dioxide, geological or biological, is the most effective? Which method to store carbon dioxide, geological or biological, has the greatest potential to promote sustainable development for local communities?The method used is a comparative case study and presents four case studies that explore the potential for CO2 storage offshore in Norway and Brazil; and in tropical forests in Mexico and Brazil.

Kalkning och vitaliseringsgödsling : synpunkter från organisationer och myndigheter samtprivata markägare i Kronobergs län

The background for this thesis is that at the beginnings of 1980´s the National Board of Forest started an experiment of lime dressing to reduce acidification in forest soil and in ground water. The purposes of this report are to explain organization?s, government?s and private landowners viewpoint on lime dressing and vitalization fertilization, some socio-economic aspects are presented. The general conclusions are that the majority of the interested party?s are positive to vitalization fertilization but the forests owner?s in generally need much more information about this topic..

Skuggvävens effekt på fryslagrade täckrotsplantor av tall (Pinus sylvestris) i upptiningsstadiet :

This project was an assignment by Sveaskog and Svenska Skogsplantor. The purpose was to study the effect of protective fabric on the thawing stage of frozen pine seedlings. The function of the protective fabric is that it should protect the seedlings against strong sunlight and create an even temperature inside the boxes containing the seedlings. The result has shown that there was no statistically significant difference when the protective fabric was used or when it was not used, although this was probably due to the weather conditions. The study was carried out under cold and cloudy weather conditions and probably would have given other results if there had been more sunny days with a higher ambient temperature.

Gremmeniella abietina-epidemin 2001 : har skogen återhämtat sig?

The fungus Gremmeniella abietina causes damage to conifers that can lead to tree death. In 1999 and 2001 the pathogen caused severe attacks in Sweden, where about 500 000 ha of pine forest were affected. Trees of all ages were attacked, but mainly forests between 30-60 years that were ready for their first commercial thinning. After recommendations from the forest agency, sanitary fellings were made to trees that had more needle loss than 85%, a total of about 50 000 ha. Economic losses have been estimated to more than one billion SEK.

Deadwood in piles or distributed : does it make any difference to saproxylic beetles?

Piles of deadwood are often retained in forests after management to support the biodiversity ofsaproxylic organisms which depend on deadwood to survive. Any knowledge about the crucial role ofpiles as suitable habitat of saproxylic organisms compared to single distributed deadwood objects thatare around the piles would help conservation actors to motivate more forest owners to supportsaproxylic organisms during their management. Therefore to give facts to this the saproxylic fauna ofdifferent pile positions (up and low) was studied and compared to distributed deadwood samplesaround each pile. Our study was focused on saproxylic beetles. Some other parameters such asdiameter, deadwood volume, pile volume and decay stage were assessed to define any effect.

Privata markägares syn på vindskadeförebyggande åtgärder :

Wind and wind damage has become a hot subject because of the storm ?Gudrun? in January 2005. The main purpose of this study was to establish how the land owners attitude toward preventive wind damage actions was changing immediately after they had been struck by a storm. The result of the study was built on interviews. In springtime 2005 a total number of 20 private land owners were interviewed. Ten of the landowners lived in the province of Småland and ten in the province of Värmland.

Analys av data från flyglaserscanning :

In forestry there are always needs of forest data to make good strategic decisions of different actions and economic winning. Usually this data gets from field-estimations made by forest workers with expensive costs and sometimes unsatisfied quality. StoraEnso Skog is a great forest company in Sweden and they have part of the responsibility of the forest own by Bergvik Skog. Bergvik Skog is owner of 1, 9 million hectares productive forest land. Both Bergvik and StoraEnso have great interest in new inventory techniques to get the important forest data. The company Foran Remote Sensing offers the opportunity with airborne laserscanning of forest and forest land. Foran got the mission of Bergvik and StoraEnso to laser scan Bergviks possession in Älvdalen, Dalarna.

Tree species traits response to different canopy cover for 34 tree species in an enrichment planted tropical secondary rain forest in Sabah, Malaysia

Tropical rain forests only cover around six percent of the world?s land area and contain around 70 % of the world´s animals and plants. Tropical rainforests have been, and still are, negatively affected by human activities. These activities lead to forest degradation which has negative impacts on production and biodiversity. Between 1970-1980 forests in Borneo, Sabah, Malaysia, was subjected to intense logging.

Rhododendron ur undersläktet Vireya - något om dess karakteristika och användning i nordiska vinterträdgårdar :

Present essay aims to introduce the reader to central topics regarding Rhododendrons of subgenus Vireya. As a result of a donation, the Swedish University of Agricultural Sciences, received a collection of Vireya from a local amateur grower, Kurt Myllenberg. Since the subgenus Vireya is uncommon in Scandinavian horticulture, the study tries to establish conditions for successful growing. The subgenus Vireya differ from the other Rhododendron species through mainly three characteristics: the presence of two tails, attached to each end of the seed; the ovary-style junction is tapering and the pedicels arises directly from a dome-like base and form an umbel and not a raceme. The subgenus is distributed mostly in the islands of Indonesia and New Guinea, but also from Malaysia to Nepal and in Australia. Since Vireya species mainly grows as epiphytes in the tree canopies, they need high drainage and not too much water.

Structure and tree diversity of lowland limestone forest on Seram Island, Indonesia

There have previously been very few studies of forests on Seram Island in the Eastern Indonesian archipelago and none before on lowland limestone primary forests. The COLUPSIA project on collaborative land use planning has therefore chosen Seram as one of two project sites. The objective of the COLUPSIA project is to establish collaborative and equitable land use planning. In order to achieve its objective the COLUPSIA project aims to improve understanding of traditional resource management and how it interacts with governmental systems, as well as enhancing knowledge about tropical landscapes and ecosystem services.The aim of this study was to contribute to the COLUPSIA project through describing lowland limestone forest on Seram Island in respect to (1) forest structure, (2) tree species richness and (3) tree species composition. We set up 5 plots, each of 0.2 ha, at one site, Mawalai, and collected data on tree variables (tree diameter ?10 cm) as well as for some other life forms and environmental data.

Inverkan av nederbörd, temperatur och frost på årsringens egenskaper hos boreal tall (Pinus sylvestris L.) :

The wide distribution range of our boreal pine (Pinus sylvestris L.) provides a great variation in growing conditions and climate/weather factors that influence the wood development of the trees. A great number of extensive studies have been conducted over the years in order to clarify growth trends of this and other species over more or less wide-ranging areas. In this thesis effects of weather factors were instead compared between different forest stands from the about same geographical location. The effects of precipitation, temperature and frost on the year ring characteristics of pine were studied in the research forest of Svartberget Vindeln, in northern Sweden. The stands differed in site index and silvicultural treatment; fertile ? high stem density, fertile ? low stem density, poor ? high stem density and poor ? low stem density.

The effect of arginine on root system development in Norway spruce (Picea abies L. Karst) somatic embryos

The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.

Vart är naturen i skärgården på väg? : skogshistoria på Ängsön-Marskär i Stockholms södra skärgård

The following thesis is a study of the forest history on the island of Ängsön-Marskär concentrating on the last three hundred years. The island is located in the administrative province of Stockholm, the local community of Haninge and it is situated approximately seven kilometres east of the island Ornö in the south of the Stockholm archipelago. The questions this thesis attempts to answer are: How where the natural resources on Ängsön-Marskär used through the centuries? How has the state of the forests developed since the 16th century? How will the nature develop onwards? The thesis is based on archival sources for Ängsön-Marskär and the surrounding areas. A field study was conducted where the entire island was investigated using an objective forest inventory method. The first map material existing over Ängsön-Marskär is from the year 1711.

Att restaurera forna tiders beståndsstruktur : ett exempel från Jämtgaveln

In Sweden today so-called "prescribed nature conservation burning" is performed due to the change in silvicultural law, certification and an increased knowledge regarding the field of fire in the forest landscape. The aim is to re-create structures and qualities made by the fire regimes of the past, though on a much smaller geographical scale. The structures and qualities to be re-created are for example broad leaf stands, trees with large diameter, heterogeneous stands regarding variables such as age and diameter. If we increase our knowledge of the constitution of forests characterized by fire, then we will be able to set goals for what achievements to reach both on landscape scale and stand scale. The aim of this paper is to try to describe how a stand from the past was composed regarding mainly the spatial arrangement and compare it with the stand of today in the same place. This to be done by using relict material, that is stumps and dead standing trees.

Kan risken för spontan contortaföryngring elimineras genom hyggesbränning? :

Sweden has almost 600 000 hectares planted with lodgepole pine, and large areas are soon ready to be clear-felled. The provenances that have been planted are producing high level of permanently closed, so called serotinous, cones. In their natural setting, the Canadian boreal forest, these cones are opened mainly after crown fires when the heat make the resin between the cone scales melt, which releases the seeds. This is viewed as an adaption to the fire regimes that prevail over the natural distribution area of lodgepole pine. Because of the short flame-exposure that occurs in a crown fire, the seeds can survive.

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