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1818 Uppsatser om Old-growth forest - Sida 1 av 122

Påverkan från den förväntade klimatförändringen på tillväxten i norra Sveriges skogar : En litteraturanalys

This is a literature review of how the climate change affects the forest growth innorthern Sweden. The temperature will rise about 5 °C with the largest increase in thewinter season (December - February) and the CO2level in the atmosphere is expected tobe doubled. Precipitation patterns will change and increase with 25-35 % and theprecipitation will be in form of rain rather than snow. Today the forests in northernSweden are entirely dominated by coniferous stands. This may shift with the climatechange and results in a larger number of deciduous trees, preferably birch will becomestronger and grow better and faster.

Kinas intåg på skogsvarumarknaden : idag och i framtiden

Because of the large economic growth in China there are many companies who have economic interests in the Chinese market. Also in the forest market companies have started to invest in China and the interest for the market is growing. The question is how the Chinese forest market will develop in the years to come? How will China?s entry on the market of forest products affect the global forest market? The purposes of this study are to describe production, consumption and trade of forest products, and China?s possible competitive advantage in the forest industry. The purpose of this study is also to describe how China?s entry on the forest market affects the world market of forest products.

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.

Grey-sided vole and bank vole abundance in old-growth forest patches of different size and connectivity

Vole populations in northern Scandinavia vary in cycles with peaks every third or fourth year as described by the National Environmental Monitoring Programme of small mammals (NEMP). Some vole species have declined in population numbers since the NEMP started in 1971, especially the grey-sided vole (Myodes rufocanus) which is nearly extinct in the forested region. Since small mammals are an important food source for several avian and mammalian predators, the decline in vole numbers is expected to have consequences for the whole food chain, especially if other vole species start to decline in numbers. This study tried to test the hypothesis that presence and abundance of M. rufocanus (a specialist species) and Myodes glareolus (a generalist species) can be predicted by patch size and connectivity of forest patches >60 years old with a minimum of 15% pine >100years old.

Metod för inventering av underhållsbehov för skogsdiken

Large areas have been ditched in Sweden during the past 100 years to improve the forest production. Ditching and also maintenance of old ditches are operations having mainly negative effects on water quality, flora and fauna and changing characteristics of soil. The purpose of this study was to suggest a method for inventory of the need for ditching maintenance in old forest ditches that takes biodiversity, water protection and forest production into consideration. Inventory methods from five Swedish and Finnish forest companies, agencies and organisations were compared. Their employees were interviewed about their handling with ditches, forest production and nature conservation.

Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)

Peat  lands  are  a  great  potential  resource  for  increased  forest  growth  in  Sweden, there  are  approximately  6.5  million  hectares  of  peat  lands,  whereof  around  70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste  land.  There  are  over  200  000  hectares  of  peat  land  that  is  already  drained and  wooded,  and  that may  be  suitable  for  fertilization.  Forest  production  on  peat soils  usually  requires  drainage  and  fertilization.  Dewatering  requires  ditching  the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The  purpose  of  this  work  was  to examine  the effects  of  potassium  fertilization  on the  growth  of  spruces  that  were  planted  on  drained  peat  land  and  how  different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance  transport  in  the  tree.  Potassium  is  also  important  for  the  carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter  resistance  of  many  species.  Potassium  is  not  found  in  any  organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was  left  without  fertilization.  All  plots  that  were  fertilized  with  potassium  grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality  estimation  of  wetlands  after  ditching  (dikningsbonitering).  The  plot  with most  potassium  produced  after  fertilizationaproximately  in  level  with  theoretical estimations.  Key  words:  Peat  land,  Fertilization,  Ditching,  Growth,  site  quality..

Skogstillväxten ca 20 år efter plantering på Flakmossen : dikningens och gödslingens betydelse vid beskogning på en avslutad torvtäkt i Värmland

This study was performed in an afforestation experiment established 1982 on an abandoned peat harvesting area, Flakmossen, in the province of Värmland, SW Sweden. The experimen-tal design include planting with Scots pine (Pinus sylvestris), in combination with various drainage intensities (20, 30, and 40 m between ditches), and fertilizer doses 0, 100, and 200 g PK per seedling applied at the date of planting. The aim of this study was to achieve more knowledge about the conditions on afforestation of peat harvesting areas, especially regarding drainage intensity and fertilization requirements, by means of determining the stand growth and yield in the Flakmossen trial. The forest growth did not differ significantly between the drainage intensities tested when the same amount of phosphor and potassium fertilizer was added. Thus, shorter distances between ditches than 40 m can not be recommended. When no fertilization was carried out seedling survival was very low, and the growth of sur-vived seedlings was poor. The largest diameter and height growth were observed in the areas where the highest dose of phosphorus and potassium (200g/seedling) was given.

Skogspolitik i Sverige

For a long time the Swedish forests were used by the landowner?s mainly for providing wood to the household itself. The wood was not, to a greater extent, considered a product to be sold. During the 1800s the industrial era led to a demanding need for wood in the industry and thus the use of forest, forest production kicked off. The forest production was not regulated by law, which led to a differentiated forest production over the whole country without consideration of re-growth.

Från gles skog och brokiga ungskogar till homogen produktionsskog : en skogshistorisk studie av Hällforsmarken under 1900-talet

The forest in the northern part of Sweden has changed dramatically during the last centuries. The forest has gone through a large-scale transformation, from it being only used locally for domestic purposes to becoming very important raw material for Sweden in the industrial age. The strategy by foresters during the second half of the 20th century has been to create pure production forests for commercial forestry. This has mainly succeeded and we have today homogenous production forests that give a high profit to the owners. The aim of the study is to compare the state of the forest in the former state forest Hällforsmarken in the years 1925 and 2000 and to interpret the changes which has taken place.

Enkätundersökning hos markägare inom SCA Skog Ångermanlands Skogsförvaltning

This report is a joint venture with SCA Forest, Ångermanlands forest man-agement area. The purpose of the study is that SCA Forest wants to know what the landowners in Ångermanlands forest management area think about SCA Forest and who they deliver their timber to. SCA Forest is the largest private landowner in Europe, with an area of about 2.6 million hectares. Today, SCA offers lumber, wood products, tis-sue and packaging and has factories all over the world. SCA Forest has five forest management areas in the north of Sweden, with the headquarters in Sundsvall. A questionnaire was sent to 265 landowners, where they had to answer 15 questions with possibilities to give comments. The survey was sent out on 21 of February with a response requested by 3 of March 125 landowners responded to the survey, giving a response rate of 47%.

Hur väl skogsägare följer åtgärdsförslagen i skogsbruksplanen : en enkätundersökning

This rapport is about how often private forest owners follow the measures proposed in their forest management plan. The survey is made in cooperation with the forest-owners association Norrskog. The private forest owners are relatively satisfied with the forest management plans and with the measures proposed. There are some differences between those who live on or near their property and those who live many miles away. The forest owners who live on their property are those who follow the proposed measure of precommercial thinning to the largest extent. That group also values precommercially thinned stands higher than thinned stands. The complete opposite is the case for the group that lives far away from their property. Almost all of the respondents thought that the forest management plan would be or had been a good help in the decision making about the forest..

Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project

The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations. The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.

Enkätundersökning om skogsägare inom Norrskogs upptagningsområde

The purpose of this report is to find out what different preferences forest owners have in the region where Norrskog have their operation area, what they prefer and think about Norrskog. The purpose is also to compare some of the questions to a similar study that was made in 2008. The study is made in cooperation with Norrskog which is a forest owner cooperative. Norrskog has about 13 000 members which is about half of all forest owners in the region. To get the answers from the forest owners, questionnaires were sent out by mail. 371 were sent out and 102 came back. There were more members of Norrskog that responded than it was nonmembers. The results indicate that the forest owners have long term perspectives, their priorities are to nurse the forest so they can get the profit later on.

Introduktion av buskskikt i ungskogar

Young stands in urban forests often lack a shrub layer, though shrubs play an important structural and biological role in forests. All layers interact with one another to form a multilayered stand, in which shrubs have a vital role.In this diploma thesis, theoretical models for forest dynamics are compared with four reference stands to detect factors, and principals for introduction of shrubs in young stands. In these stands four different ways of introduction were found. In one trees and shrubs were planted together at the same time. Shrubs spontaneous spread under a canopy of mature forest, in another.

Fågelbär (Prunus avium L.) - överlevnad, höjdutveckling och skador i unga planteringar på småländska höglandet :

Plant survival, plant damage and height growth were studied in nine wild cherry (Prunus avium L.) plantations in southern Sweden established between 2000 and 2002. All stands were located to the county of Småland. The survey was conducted during May and June in 2007. During the survey the height, diameter and quality of the cherry trees were recorded. In one stand, red ? berried Elder (Sambucus racemosa L.) was a dominant species.

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