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838 Uppsatser om Mixed stands - Sida 6 av 56
Anpassad skötsel - exempel på hyggesfritt skogsbruk i Mellannorrland :
Total protection is often the option chosen when protecting forests with high environmental values. An alternative to total protection is application of management regimes that do not interrupt continuity of tree cover. This study focuses mainly on continuous cover forestry (CCF) in forest stands already protected. All objects are situated in the county of Jämtland in northwest Sweden.
The purpose of the study was to attain a greater knowledge about CCF practices.
Environmental variables determining the occurrence of the red-listed Carbonicola anthracophila and C. myrmecina in boreal forests
The global biodiversity loss is mainly due to human activities such as an intensification of forestry. Boreal forest ecosystems in Fennoscandia are characterized by disturbances such as forest fires, storms and floods. However, industrial forestry practices suppress forest fires and change the landscape, leading to a loss of habitats and associated species. Particularly lichen species with slow adaptation abilities and a strong substrate specificity face an extinction debt in boreal forests since their substrates are long-lived but no longer created. In this study the species-substrate relationship of two red-listed forest-fire dependent lichen species Carbon-icola anthracophila and C.
Mässa tur och retur : En intervjustude, enkät och observation
This paper deals with the question of why companies choose to go on trade fairs and exhibition examines how the media works. The essay's main focus is on stand contractors and why those hired to produce other company stands. The study is based on three interviews, a visit to a trade fair and a questionnaire survey. Together with the relevant literature is given a clear picture of how companies are thinking in their choice of attending the fairs, but also why stand contractors are involved in the process. We concluded that some companies do not know why they participate in fairs and many feel compelled to contribute to not be forgotten in the market.
Digitala fotogrammetriska arbetsstationer för skoglig flygbildstolkning :
SCA Skog has taken the initiative to this Master?s thesis. Today SCA Skog has a great need to update their informtion on young forest stands across large areas. Traditional field inventory methods for updating stand databases are expensive and time consuming. However, the inventory could be made more efficient if stand boundaries and stand characteristics are derived from aerial photographs.
Skötsel av älgskadade bestånd :
Sweden has today the highest moose (Alces alces) population in the world. The population has been very high since the late seventies and in the beginning of the eighties there was a big ?moose explosion?. The main food source for moose during the winter is young pine (Pinus sylvestris) and birch (Betula spp.). The high moose population has therefore lead to high damage on pine forests over big areas.
Risken för spridning av röta vid förröjning i granskog i södra Sverige :
Root rot causes large economical losses for Swedish forestry. The spread of root rot can partly be prevented by treating the spruce stumps in thinnings. Late pre-commercial thinning (PCT) is one of the forestry measures where stump treatment is not used. Late PCT can be defined as: The act of cleaning the stand with the aim of improving accessibility and sight within the stand, and so to increase the mean stem´s volume during the first conventional thinning.
The aim of this study was to examine how late PCT is performed, its spatial extent and if it aids the spreading of root rot. The study was limited to encompass late PCT before first conventional thinnings in spruce stands in southern Sweden.
Samples of spruce stumps were taken from four stands where late PTC had been carried out.
Analys av individinriktad ekskogsskötsel i Blekinge : en metod för tillämpning i ett kontinuitetsskogsbruk?
Ett ökat brukande av skog enligt skötselprinciper som leder till skiktade beståndsstrukturer, en blandad trädslagssammansättning och kontinuerligt skogbeklädd mark har potential att öka den biologiska mångfalden och värdet för rekreation (Emborg m.fl. 2000, Berg m.fl. 1995, Mattsson & Li 1994, Holgen m.fl. 2000). I ljuset av detta, tillsammans med svårigheterna som finns att nå goda ekonomiska resultat vid skötsel av ädellövskog (Lindén & Ekö 2002), ses det idag som angeläget att uppmärksamma och studera alternativa skogsskötselmetoder (Cedergren 2008) .
I östra Blekinge har ett antal skogsägare under längre tid praktiserat en metod att sköta naturligt föryngrad ek i blandbestånd som går ut på att, mer eller mindre tidigt, frihugga ekhuvudstammar, och att dana kvalitet genom stamkvistning/beskärning.
Attityder och kunskaper kring hållbara matvanor
The Purpose of this study was to examine what knowledge and which attitudes there are about environmental friendly food in the society. To do so an essay were constructed and distributed to five different working places. Altogether there were 50 essays distributed and 43 were returned. The main result; the respondents think that it is important for people to learn how to consume food in a more environmentally friendly way. The majority of the respondents recognized the eco-label KRAV but the European eco-label and Demeter were not recognized in a less extent.
Ifrågavarande kronopark skall benämnas Skatan : en skogshistorisk analys av Ekoparken Skatan
People have utilised and influenced the boreal forest for many centuries. Prior to the industrial revolution during the 19th century, however, human use primarily only had a low impact on the forest. When the timberfrontier swept over the country, the Swedish forests came to change for ever. The study site for this thesis is situated in the northern part of the county of Västerbotten, Sweden, and has previously been a National forest. Today the area is an ecopark and the land is owned by the forest company Sveaskog.
Björkbarksextrakt, BBE : en lönsam lösning på betningsproblematiken?
The calculations in this thesis are evaluating the profit as a consequence from treating young stands of pine in Sweden with birch bark extract, BBE. Treatment is to be done with the object to lower or fully reduce the moose browsing on pine. The study is made in three versions. The results from each version separately will follow below.
Version I.: The size of the moose population is in no way affected by the reduced resources of food as a consequence of large scale treatment with BBE on pine. Results show profit at a 3 percent level of interest with the exception of treatment program with more than 4 treatments all together and with the exception of Västerbottens Län with an early first treatment.
Version II.: The population of moose decrease from 10 to 5 individuals per 1000 ha as a consequence from large scale treatment with BBE on young pine stands.
Kvantitativ studie om knappsatsdesign och knappstorlekars påverkan på träffsäkerhet
A mobile testing application using Unity was developed to analyse what impact button sizes and button layouts has on the accuracy of touch as well as the time to finish a labyrinth. This was tested on a Nexus 4 phone. 28 users navigated a small object through a labyrinth in which they collect keys to open the door to the exit. Each participant did the test 6 times with different combinations of button size and button layout each time, done in a random order. Hits, misses, completion time, order of button size and order of button layout was collected and then visualized using R.
Rumslig fördelning av grov gammal tall i Uppsala stad med tallticka som indikator på höga naturvärden :
Fragmentation and reduction of forest area is a threat for many forest species and their habitat. Deficiencies in forest quality, such as lack of dead wood and old trees, are one explanation of the threat. The most important action to prevent the continued loss of forest types is to protect forest, but also to restore and to create areas that not previously had high nature values. Hence one of the key strategic roles for Fritid- och Naturkontoret, Uppsala municipality, is to monitor biodiversity in the context of urban planning.
The majority of the Uppsala municipality residents live in urban areas and most of them spend some of their spare time in natural areas in cities and their immediate surroundings. Exploitation in and around Uppsala is high, but it is important that there is enough nature close to houses to meet the residents? needs of recreation.
Plantinventering och plantkontroll med digitala bilder från helikopter :
This study was carried out as a commission from Holmen Skog, district ?Egen skog? in Norrköping. During October 2006 several stands were inventoried by aerial photos from helicopter. The stands were those for which the next action proposed was plant inventory or plant check. The photos were interpreted and the number of stems was calculated.
Mekaniserad ungskogsbehandling för röjning och skörd :
Earlier attempts at mechanising pre-commercial thinning have been met with varying degrees
of success. Most attempts have been based on techniques where residual stems are straddled.
Early treatment is essential to limit damage on residual trees. One part of the present study is an evaluation of mechanised pre-commercial thinning using the new Vimek 404R. Vimek 404R is a fairly small machine that permits selective removal of stems, making it potentially suitable also for areas overdue for pre-commercial thinning. The study established the level of performance for the machine, as well as the improvement needed to make it an economically viable option.
Planteringsförbandets inverkan på bildningen av kärnved hos tall (Pinus sylvestris L.) : en modellsimulering av planteringsförbandets inverkan?
The current state of knowledge indicates that there is more than one factor that initiates heartwood transition. This study supports its hypothesis on the theory that heartwood is formed by a fixed fraction of the annual growthring, 0,5 to 0,8 rings. To calculate heartwood volume modelings were carried out in four different pine stands with different spacings, 0,75, 1,25, 1,5 and three meters. The model indicates heartwood diameter (HWD) and is based on four explanatory variables, height (H), crown ratio (CR%), diameter breast height (DBH) and tree height (TH). The shifting plant spacing results in varying growth rate in the juvenile stage.