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3373 Uppsatser om Fast growing tree species - Sida 8 av 225
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.
Fjällfåglar : En jämförande studie från dal till topp i ett nordligt och sydligt svenskt fjäll
Title: Mountain birds ? a comparative study from valley to mountaintop in a northern and southern Swedish fjeld Author: Kristian Zackrisson Abstract Main aim in this study was to increase the knowledge about birds in the Swedish mountain area. Three questions were asked: 1) Which bird species can be found during the breeding season along a low mountain slope from a forested valley to a mountaintop with bare mountain environment? 2) Do the number of species and individuals differ in different elevation zones? 3) Is the composition of bird species along a low mountain slope the same in the Kebnekaise mountains inLaplandand the Grövelsjön mountains in Dalarna? Bird census in two study sites located in the Kebnekaise mountains and the Grövelsjön mountains and subsequent analysis of the results from the bird census was the main parts in this study. Totally 20 bird species were found along a low mountain slope in the Kebnekaise mountains.
Gallringsinventering från helikopter utrustad med profilerande laser och kamera för låghöjdsfotografering
Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.
Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :
Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization.
It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared.
During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.
Restoring biodiversity in degraded secondary rain forest in Sabah, Malaysia : natural regeneration of trees after restoration treatments
Many tropical rain forests has been lost or degraded as a result of human activities and environmental factors. Since the level of biodiversity is high in the tropics, maintaining these areas is of great importance. Forests like these are often assumed to benefit from forest restoration and rehabilitation. The INIKEA project area in Eastern Sabah, Malaysian Borneo, aims to improve biodiversity and/or species richness in the degraded forest through enrichment planting with indigenous species. The objective of this thesis was to evaluate how different treatments (liberation, gap-cluster planting and line planting) affect the biodiversity of natural regeneration in different forest types in the Rain forest Restoration Experiment, located in the INIKEA project area.
A literature study and survey of sycamore maple (Acer pseudoplatanus L.) in southern Sweden
Sycamore maple (Acer pseudoplatanus L.) is a common broadleaved species throughout Europe, however often
of minor interest to the forest sector. There is currently a lack of research on sycamore maple, and some of its
characteristics have throughout history contributed to a negative reputation in both literature and the forest
society. Since broadleaved species in general are of great importance to the forest sector in Europe and
presumably of enhanced significance in the future, deepened research is needed and particularly Swedish.
With a desire to hopefully increase the interest for sycamore maple, was the objective of the study to examine
the current status of the sycamore stands in southern Sweden. The study was carried out both as a survey with
inventory field work and as a literature study. Parts of the latter mentioned is also presented in the
introduction.
The study shows that the majority of the sycamore stands in Sweden are growing well, producing fairly high
qualities and volumes.
Sköldpaddsdammen som en naturlig oas på Mallorca : en fallstudie
This study shows how to plan a pond with an ecosystem which although it will have turtles living in it will not need to be cared. I will also demonstrate how this pond would be designed to work in the natural landscape on Mallorca.
The background to the study is that I am interested to investigate how plants that we in Sweden are using as indoor plants are growing in their natural landscape and how to build a land-scape with them. The study highlights different cleaning-systems that can be used to clean a pond in a natural way. A comparison will be made between the conditions of an exterminated turtle-species which will live in this environment and a species that is easier to care for.
Skötselåtgärder vid nyetablering av skyddszoner vid bäckar i södra Värmland :
Buffer zones play an important role for the water quality in our watercourses. When harvesting a forest close to a watercourse a buffer zone should be left. When it's not left, it will lead to radical changes in the environment for the water organisms. The overall purpose of this thesis was to illuminate the production- and environmental thinking when establishing new buffer zones in south of Värmland. The partials goals were to determine choice of tree species, ways of regenerate, occurrence of soil scarification and the occurrence of machine tracks in newly established buffer zones.
Skogsbrukets erfarenheter av Poppel Populus sp. i Skåne :
In Europe poplar plantations has been planted for more than one hundred years. In the first plantation was made in 1940. The interest for poplars has since then shifted over the years and has for long periods been very low but is now slowly increasing again. The main reasons why poplars are becoming more interesting are because of their great production potential. Nevertheless, the knowledge of how to mange poplars in Sweden are very low and very little research has been done concerning management of the species.
The objective for this study was to; 1) investigate and document experience and results obtained in practical Swedish forestry, 2) to give a fair picture of the perceived advantages and disadvantages that the poplars has for the forestry, 3) document what the foresters that has experience and those who has no experience of poplar plantations thinks about the potential of poplars.
Produktivitetseffekter av flerträdshantering
The main purpose of this study is to investigate the productivity effects of multiple tree handling in thinnings. Other important elements have been to investigate in which extent multi-tree handling is used in stands with different stem volumes and the impact of collecting partially delimbed fuelwood assortments has on harvesting performance.
The study is based on data from thinnings in Sydved and contractors' operating activities. Collection and compilation of operating schedules, number of stems and surveyed volumes from several contractors and a large number of executed orders underlying the results.
Multiple tree handling is used to a much greater extent at lower average stem volumes. Prediction models for productivity of the multiple-tree handling harvesters in the study differ from the productivity models for single-tree handling. In the model developed in this study productivity is not as dependent of stem volume as reference models.
Indirekta effekter på marklavars abundans och diversitet vid ökad kvävehalt i marken : en jämförelse mellan opåverkad och lågintensivt brukad mark
Lichens are adapted to bright and sparse forests on oligotrophic ground. Due to a slow growth rate and high light demand lichens will suffer from competition in eutrophic environments. Therefore, lichens have disappeared from managed forests where the forest industry has increased the productivity. A reduced abundance of lichens will affect both biodiversity of the forest and the reindeer winter graze lands. It is important to understand how and for how long fertilization affects the abundance and diversity of lichens in order to protect lichen rich ecosystems.
We have registered the biomass and number of lichen species in eight plots (four nitrogen rich and four nitrogen deficient) and compared fertilized Sami settlements with their oligotrophic surroundings in the nature reserves of Tjeggelvas.
Skötselmetoder för bestånd med produktions- och naturvårdsmål :
This study is made on assignment by the local board of forestry in Skåne,
Blekinge and Halland.
The change of the forest law 1994 brought a new type of management plan.
A more active planning was introduced in order to equate the environment goal
with the production goal. The purpose with this study is to give a better picture of
how planning for nature conservation in production forest is made and to develop
support for selection of silviculture methods for stands with combined goals. With
combined goals means production forestry with a reinforced consideration to both
nature and culture, called PF-classified stands. This was done by:
? Describing silviculture models from the literature that are possible to use
for stands with combined goals.
? Describing silviculture models that is used in practice in stands with
combined goals.
? Describing how the classification of stands with combined goals is used.
Which means, were in the terrain, with which frequency and in which type
of forest PF-classification is used.
? Comparing differences and similarities of theoretical and practical used
models.
The study was done partly as a literature study and partly as an interview study of
forest planners.
V?n eller Fiende? En Studie om Kommunalt Milj?ansvarigas Perspektiv kring Invasiva Fr?mmande V?xtarter
Invasive alien plant species have historically caused major damage to ecosystems and are
considered to be amongst the greatest threats to biodiversity globally. The lurking threat of
harm to well functioning ecosystems has led to the development of global and regional goals
and regulations which seek to stop the spread of invasive species. The Swedish
Environmental Protection Agency has proposed a list of species that are specifically harmful
to the Swedish flora and fauna, which includes (amongst others) garden lupin. The
management of invasive species is however largely dependent on local actions, making
municipal public servants key players. This qualitative study uses interviews to investigate
how municipal public servants who are responsible for managing invasive alien species view
this work.
Julgransodlingar i Sverige : utbud, efterfrågan och lönsamhet
This thesis is about Christmas tree plantations in Sweden, and if its profitable to produce Christmas trees in Sweden. Sweden has 4,3 million households, 3 million of these households buys Christmas trees. 80 % of these Christmas trees are Norway Spruce (Picea abies), which is the most common Spruce in Sweden. Every year over 170 000 Christmas trees are imported to Sweden. The main import comes from Denmark.
Spatt relaterad till tarsalledens vinkel
The effectiveness of Phlebiopsis gigantea to prevent spore infections from Heterobasidionannosum and Heterobasidion parviporum on hybrid larch stumps were investigated in fivestands in southern Sweden. All sites are former forest land and the age of the trees wasbetween 9 and 13 years.The study was implemented in August 2010, a month where spore dispersal should be great.The five sites were located in previously un?thinned monocultures of hybrid larch. The sporeload in the air was studied with the help of spore traps from three different tree species;Norway spruce, Scots pine and hybrid larch. A total of 146 spore traps, evenly distributed inall five sites were analyzed.