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455 Uppsatser om Basiphilous pine forests - Sida 6 av 31

Skötsel av ekholmar och eftersatta ekbestånd på låga boniteter : en fallstudie

This case study is made on assignment of Södra, region Öst, as a part of a campaign promoting more active management of the oak forests in the region. Hardwood trees of good quality, especially oak, has a high value due to that the sawn material is highly estimated by the market. It is important that the Swedish oak forests are managed in a proper way in order to meet the future demand. Södra has therefore decided to increase the focus on oak in the Kalmar region and they would like to find out if continues cover forestry (CCF) under certain conditions can be an appropriate management model. The motive is to make use of the existing oak forests more efficient, not just considering well managed forests but also the more neglected oak forests, on poorer soils. Thus, the objective for this study is to examine if CCF is appropriate method in the three stand types; broadleaved mixtures oak forest, oak islet, and oak/spruce forest. Existing management models were surveyed in the literature.

Brand i Fulufjällets nationalpark : en brandhistorisk analys med förslag för framtida skötsel

Fire has historically been of great ecological importance in the boreal forests of Sweden. The forest fire regime has, however, varied between different parts of the country. The objective of this thesis is therefore to investigate the fire history in Fulufjället National Park and, on this basis, give suggestions for future fire management. The reconstruction of fire history was done by cross-dating fire scars in samples taken from living and dead Scots pine (Pinus sylvestris). Local fire chronologies were established at 17 points in the forests in and around Fulufjället National Park by cross-dating fire scars on 54 samples. The oldest year-ring dated from year 968.

Ett träd för ett annat

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.

Hur ska tall- och gran bestånd i Götaland gallras för att minska risken för vindskador?

With knowledge of how the southern Swedish forests have been affected by storms the past years, this study intended to find out which factors affect the storm firmness of a stand the most. The study was based on data from stands in the, by the storm Gudrun, affected area. The results of the analyses that tested the stand factors that influence the amount of storm damage to the greatest extent showed that the storm sensitivity of Norway spruce stands were largely due to previous management actions. The factors that could be controlled by thinning and had relevance of storm damage standpoint, according to the results were; the dominant height, volume, basal area weighted mean diameter and stand age at last thinning. In this study, these results are not as clear for Scots pine.

Utbyte av massaved och biobränsle i några typbestånd av Contorta :

The aim of this study is to describe a number of type stands of lodge pole pine in Norrbotten with respect on stem volume and total biomass. Further questions to answer is if there is stand characteristics that make the stands more suitable for pulpwood in early thinning, or if it is better to apply whole tree harvest. The study shall also give an indication if bio energy can be an economical interesting alternative for Sveaskog. Sampled trees represented the variation in the different stands. Five trees were selected from each stand to represent that stand. Stem volume and biomass (kg dry weight (DW) per hectare) for each fraction was calculated.

Utilization of different habitatsin Colobus angolensis palliatus in the forests of Diani Beach, Kenya

The Angolan black and white colobus monkey (Colobus angolensis palliatus) is an arboreal primate that inhabits coastal forest fragments on the south cost of Kenya and is consequently vulnerable to forest fragmentations. The study was carried out in March and April 2011 in Diani Beach in Kenya where two of the largest populations of the species are distributed. This study is a pilot study to test methods for a Master?s thesis. The aim was to investigate any variations in use of two habitats of C.a.

Brandrelaterade insekters lokala artrikedom i förhållande till olika miljövariabler : Fokus på betydelsen av konnektivitet på brandfält i boreal skog i Västerbottens län

The last century, forest fires have decreased in frequency due to efficient fire-suppression along with the growth of the industrial forestry. Since 1990, fire has been reintroduced under controlled forms to recreate burnt habitats. Many species that are dependent on, or benefits from, forest fires have increased since fire was reintroduced. The importance of connectivity is often addressed in ecological research. This is particularly important for species dependent on short-lived habitats such as burnt forests.

pH-sensitivity in boreal streams ? the influence of landscape characteristics

The goal of the society to increase the proportion of renewable energy has led to an increased demand of bioenergy e.g. forest biomass. However, there are concerns that removal of biomass will lead to decreased base cation concentrations in the soils and acidification of streams. In order to find in which types of landscape removal of branches and tops could have such negative effects, this study aims to analyse the relations between pH-sensitivity and landscape variables in the Bothnia Bay water district. GIS and digital geographical data were used to analyse the landscape in subcatchments.

Influence of prescribed burning and/or mechanical site preparation on stand stem density and growth of Scots pine stands above the Arctic Circle : results 9-19 years after stand establishment

Prescribed burning was commonly used for site preparation in Sweden to establish new forests until the 1960?s, when mechanical scarification was introduced. During recent decades the interest in prescribed burnings has increased again, mainly due to certifications of forestry stating that 5% of the regeneration areas should be burned on dry and mesic soils. The objective of the study was to evaluate actual influence of prescribed burning compared to other site preparation on stand stem density, growth parameters and tree damages for Scots pine (Pinus sylvestris L.) after direct seeding and planting. The study also attempts to simulate growth until first thinning.

Förekomst & kostnad av kapsprickor i stormaskadad skog

The aim for this study where to investigate the frequency of cutting cracks in saw timber harvested in the storm-damaged forests in regions where the storms Hilde and Ivar hit. The idea for this work came from one of the region?s biggest actors, SCA Skog and Jämtlands district. The purpose where to find out how big proportion of the saw timber that contains cutting cracks, their financial cost in lost wood value and also give advice and suggestions on how to work against the frequency of cutting cracks. For the field-study some guidelines where used to make sure that the samples were taken under the same conditions, they were: ? The field-study must be performed under harvesting of storm-felled forest, which are horizontal/inclined trunks. ? The averaged sized tree will make it possible to harvest saw timber. ? The trunks can?t be root cut. A methodology called in Swedish ?Trissmetoden? was used because it is the most frequent used methodology in earlier performed studies and the only one that can be used I field. Under the field-study data were collected from 570 saw timber logs, 30 logs from each one of the tested harvesters.

Identifiering av gallringsbehov med hjälp av flygburen laserskanning :

Thinning is one of the most important silvicultural activities in middle aged forests, partly to minimize damages and partly because it leads to earlier harvesting revenues and increases the value of the remaining trees. There are many different indices used to describe stand density and thereby the need of thinning in forests today. Studies have shown that forest variables can be estimated with high accuracy using airborne laser scanning and it is likely that the method could also be used to estimate forest density indices. In this study, the possibility of using the forest density index ?H² to determine and map priorities for thinning operations for a forest area was examined.

Lövsuccessioner i sluttningar längs nedre Umeälven :

Secondary deciduous forests, which have their origin in earlier pasture- and meadow-land in slopes along the lower reaches of the Ume river, are thought to contain high nature conservation values, in spite of a relatively low age. The aim of this study was to clarify how factors as historical use, exposition, disturbance dynamics and successional age influences the conservation values in these types of riparian forests and how this can be implicated in the practical work with conservation and management at Umeå municipality. Sample plots were placed in seven stands with a variation of their historical use, exposition, disturbance dynamics and age of succession. Conservation values as structure, tree-regeneration, abundance and composition of vascular plants, amount of dead wood and the abundance of signal-species were measured and registered. The species composition and especially the composition of tree species, differed between forests with different exposition and different historical use.

Skötsel av torvmarksskogar - vad vet egentligen Västerbottens skogsbolag?

About a quarter of the Swedish land area is covered with shallow or thick peat. There is a potential to increase forest production in Sweden with almost 2 million m3/year in selected peatlands with low conservation values. This increase can be accomplished by drainage, complementary drainage, ditch maintenance operations and fertilization. The purpose of this study was to determine the level of knowledge regarding the management of forests on peatlands and was restricted to selected forest companies in Västerbotten County, with offices in Umeå. Three companies were chosen, SCA, Holmen and Norra Skogsägarna.

Effekter av kalavverkning på mindre boreala sjöars vattenkvalitet

Forestry is an important industry in Sweden, with clear-cut as the most commonly used method for harvesting. Here the long-term impact of clear-cut on lake water quality (dissolved organic carbon (DOC), nitrogen, phosphorus and pH) has been investigated, based on 23 lakes sampled during autumn. Data for additional 15 lakes sampled for the Swedish monitoring program were also used. Lakes were classified as 5, 25, 40 and 60 year based on data of the forest age in the catchment, gathered from the Swedish national forest inventory. Clear-cut lakes were classified as 5 years (>20% of the catchment clear-cut during the last 10 years).

Ändamålsanpassad TINA-sortering av sågtimmer :

Swedish sawmills of today suffer from unsatisfying economy with high costs and low benefits. The economical result depends on how well the sawmill can use their raw material. Iggesund Timber AB, a sawmill in the Holmen group, produces a large amount is enduse orientated products for the woodworking industry. Therefore the aim of this student thesis was to investigate the possibility of automatic enduse orientated quality grading of Scots Pine (Pinus sylvestris) saw logs by using a gamma-ray log scanner. Iggesund Timber AB has the possibility to grade logs automatically with TINA, a two way gamma-ray log scanner. Grading and classification of Scots Pine logs in Sweden today are mainly manual but can in some rare cases be automatic.

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