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3373 Uppsatser om Fast growing tree species - Sida 11 av 225

Hyggesbränning på Orsa besparingsskog - en studie på tillväxt och föryngring,15år efter etablering

The main purpose with this study was to investigate whether the tree growth differs or not in prescribed burnt areas compared to mechanically scarified. Together with the result from the main purpose, answers of whether it's possible or not to combine nature conservation with tree production in prescribed burnt areas was presented. In these areas the regeneration were analyzed to see if there was enough tree plants to comply with the Swedish Forestry Act regulations terms for approved regeneration. A field survey was conducted at 6 objects, three objects for prescribed burning and three for mechanically scarification. All objects were planted within the same year.

Sitkagranens potentiella merproduktion jämfört med vanlig gran i Hallands län

Sitka spruce (Picea sitchensis) is not considered to be a native species to Swedish forests. It´s origin is the pacific coast of Northern America, an area that is dominated by a coastal climate which makes it likely to believe that it would be well suited for growing in the south-west of Sweden. This study aims to investigate the gain in production that can be reached by growing sitka spruce instead of Norway spruce (Picea abies) in the county of Halland. A regression model based on data from forest experiments was produced to explain the gain in production. This model was based on elevation and annual precipitation. The model was then used to create a map layer in arcGIS that shows the gain of volume in comparison to Norway spruce in percent. An analysis was carried out to find what share of the forestland in Halland county that fell into four different classes of production gain.

Attityder till återintroduktion av visent i Sverige

The European bison is a species which is no longer present in the wild fauna of Sweden. Reintroduction has been proposed in several different forums. Reintroduction is an attempt to reestablish a viable population of a species in an area to which it is native. To make such an operation successful in the long run it is essential to know the attitudes of the stakeholders involved. This study has sensed the attitudes towards reintroduction of European bison to Sweden.

Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?

Fungi are everywhere around us and recently, there has been an increased interest in their role and importance in the forest. The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials. Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate. Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry. A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects. The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored. Researching fungi knowledge and interest, a survey was distributed to five groups of people. The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.

Kväveomsättning i gräsmark med olika artantal och artsammansättningar :

This study was carried out at the Swedish University of Agricultural Sciences, Dept. of Agricultural Research for Northern Sweden. The aim of the study was to determine how plant species richness and diversity influence the nitrogen pools and nitrogen fluxes in the soil. Plant and soil samples from a biodiversity experiment in grasslands were used. Thirty plots with 12 grassland plant species (legumes, grasses, and non-legume herbs), combined from 1-12 species were investigated.

Utvärdering av flygbildstolkning för uppskattning av beståndsvariabler och åtgärdsförslag i ungskogar : en studie på Korsnäs Skog och Bergvik Skog AB i västra Dalarna

In Korsnäs district Dala Väst there were problems with information concerning their younger forests, mainly those in pre-thinning stage. They were divided into large, heterogeneous stands with often poor stand data quality. In 2006 an aerial photo interpretation of the young forests was conducted to fix these problems. Necessary information to get from the interpretation were silvicultural management suggestions, new stand delineation and new stand data. This thesis is supposed to evaluate the quality and usability of the interpreted data. To evaluate the interpretation an objective control inventory was conducted in 60 stands, either through callipering or counting stems.

En intervjustudie om sjuksköterskors upplevelser av teamarbete på en akutmottagning

Pre-workout (PWO) is one, fast-growing, supplement on the market that promise fat burning, bigger muscels and energy and by buying these expensive supplements, you can get your dreambody faster than others. This study is mainly about researching why people use PWO and what experiences they have about using these supplements. By using a qualitative method I have found out that the participants mainly uses PWO to get energy and focus. This study also shows that my participants thinks that there is a difference in energy between using and not using PWO..

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Föryngring i stormfälld rekreationsskog : en jämförelse mellan föryngring i produktions-, rekreation/produktion och rekreationsskog.

When the storm Gudrun hit Sweden on the 8th and 9th of January, many recreational forests in southern Sweden blew down. For this reason there is a demand for new regeneration methods as to how these storm-felled areas should be regenerated and with what species. In this study the forest is divided into three areas: production, recreation/production and recreation. The first area is a forest with production as main goal and these kinds of forests are located a bit from the city. The second type ? recreation/production forest ? has two equal goals: production and recreation, and is located close to the city.

Undersökning av självspridning av contortatallen i norra Sverige

Over the past 40 years 600 000 ha of lodgepole pine (Pinus contorta ssp. latifolia (Engelm.) Critchf.) has been planted in Sweden (280 000 ha on SCA's forest land alone which represents about 15% of the company's total forest land area). In the early 70's SCA situated a number of experimental stands in order to investigate different aspects of the exotic tree, primarily growth rate. To be able to compare the two species plots with scots pine (Pinus sylvestris L.), this species was also planted at the same time and under the same conditions. A number of questions should always be raised when exotic species are introduced in an ecosystem. Invasiveness, the pathogen situation and purely ethical issues should be discussed.

Svartgran ? ett alternativ när allt ser mörkt ut? : en kartmodell för att visa lämpliga ståndorter för odling av svartgran

A common problem in forestry is plant death caused by frost. The risk of frost is highest on wind protected, flat or low-lying areas in the terrain. Here you often have regeneration problems with Norwegian spruce which is especially sensitive to spring frost. Swedish tree experiments have shown that the black spruce can be a suitable alternative on these areas, for example on moisture frost prone areas. The species originates from North America and its pioneer tree characteristics make it more frost hardy than Norwegian spruce.

Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population

The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation has been done by the Swedish Environmental Protection Agency. In this work I have therefore investigated how a translocation of the species succeeded after 17 years. I aimed to study the species dispersal biology, its substrate preferences and the supply of suitable wood on this site. The study was performed during 2012 in Pansaruddens nature reserve close to Uppsala in Sweden, which is a spruce dominated forest.

The effect of cold stratification on germination in 28 cultural relict plant species : with the purpose of establishing germination protocols

Cultural relict plant species from the Nordic countries have been collected by the Nordic Genetic Resource Center (NordGen) for the purpose of conservation. To ensure high seed vitality in store, regular germination tests need to be conducted. It is important to get a correct viability status, but the knowledge of seed dormancy in the cultural relict plants is often poor. The objective of this study was to investigate how seed dormancy is affected by cold stratification. The study includes 31 accessions from 28 species with the purpose of establishing germination protocols.

Spridningsmönster och potentiella spridningsytor hos invasionsarten stor bockrot (Pimpinella major) i Tullgarns naturvårdsområde : ett framtida problem för områdets diversitet?

An organism that is transferred from one place to another, causing major problems to the native species is termed invasive. Its natural dispersal across barriers may have been prevented but as man has turned able to rapidly travel all over the world organisms are brought to sites where they were never before observed. Adding the increasing global warming organisms may find it necessary to move around even further. This might cause major disturbance to the biological diversity, and hybridization and homogenization is one of many scenarios that could disturb the native diversity. In Sweden more that 2/3 of all alien plant species have been introduced to disturbed areas and the major introduction mechanism is gardening.

Ny fast förbindelse mellan Helsingborg - Helsingör.

Specialarbete, 15 hpSvenska som andraspråk, SIS 133VT 2012 Handledare: Håkan Jansson.

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