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3373 Uppsatser om Fast growing tree species - Sida 7 av 225
Fältskiktsarter i naturlika planteringar : vilka råd kan ekologer ge?
This paper appeals to professionals working with green questions. It intends to create a discussion about which plant species that can be established in a fieldlayer of a naturelike planting on fertile agricultural land. To initiate the essay, a studie of which values that can be connected with an establishment of a fieldlayer was performed . A part of Tor Nitzelius Park in Alnarp, a so called naturlike planting on fertile agricultural land, was used as a model for the choice of species. With the aid of soil values, photos and a list of current species, interviews with four ecologists were performed.
Bestämt eller obestämt? En kontrastiv jämförelse av ett antal engelsk- och kinesisktalande inlärare av species i svenska.
Specialarbete, 15 hpSvenska som andraspråk, fördjupningskurs SSA133Vt 2012Handledare: Hans LandqvistExaminator:.
Species diversity and geographical distribution of Fusarium species on winter wheat in two regions in Sweden
Various Fusarium species causes some of the most common cereal diseases worldwide. Besides the yield losses that can be a result of these diseases, strains from several Fusarium species can produce mycotoxins, some very toxic. The aim of this study was to investigate which Fusarium species and how many that occurred in winter wheat grains from Mälardalen and Kalmar län, if there was any difference in the distribution of Fusarium fungi between the regions and the potential within species to produce mycotoxins belonging to the group trichothecenes. Winter wheat grains collected in 2009 from ten fields (unsprayed plots) in the two regions were analysed for Fusarium species. PCR was used to amplify the TEF region where after the samples were sequenced.
Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China
An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.
H?RNERVMOSSANS P?VERKAN P? LJUNGHEDENS ARTM?NGFALD: En f?ltstudie fr?n Sandsj?backas naturreservat
Campylopus introflexus is a moss species that originates from the southern hemisphere and has spread worldwide during the 20th century. Today it is classified as an invasive alien species in many countries, and it has been seen during inventories that it has become widespread in Sweden as well. The purpose of this essay is to contribute to new knowledge about how this moss affects species diversity on Calluna heathlands in Sweden. The study includes both fieldwork and an analysis of scientific literature on the subject, and the question that is answered is if C. introflexus has an impact on species richness in the heather peat.
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.
Picea mariana ((P. Mill.) B.P.S), P. abies (L.), Pinus contorta (Dougl.) och P. sylvestris (L.) : en jämförelse av produktion och potentiell kvalitet hos försöksbestånd i Jämtlands län
Swedish forests are dominated by just two conifer species Norway spruce and Scotch pine. They are not able to achieve the highest possible production or fulfill industry demands for raw materials. The introduction of exotic conifers can potentially meet these shortcomings and present a relevant solution.
This study was conducted in a block experiment with ten blocks planted in 1987 by SCA in North Sweden. The objective of the block experiment was to study if Black spruce is an appropriate alternative to Lodgepole pine, Norway spruce and Scotch pine on different site classes.
Betula : arter och sorter
As birch is one of the most common trees in Sweden, and probably one of the easiest for
someone who lives here to identify, it is interesting to note that most people do not know
how variable the genus is and how widely it is distributed across the northern hemisphere.
One can find birch growing at both high and low elevations, demanding different soil
conditions and preferring varying amounts of sunlight. Many people may also be surprised to
hear that the colour of the bark can vary from bight white to almost black, and different
shades of pink, orange and red can also be displayed. This, together with the astonishing
beauty of the genus, the important role as a pioneer in many ecological systems and the
difficulty in sorting out the taxonomy of the genus, constitutes the background of this thesis. The thesis is written at the Department of Landscape Development in Alnarp, Sweden with Kenneth Lorentzon, researcher at the Swedish University of Agriculture as a supervisor. The aim of this thesis is to highlight which species and cultivars within the genus Betula could be appropriate for horticultural use in Sweden.
Ajuourhållning av ungskogsdata med hjälp av digitala flygbilder :
The purpose of this study is to investigate whether it is possible for SCA to update their stand register with use of digital aerial photos photographed with a Zeiss/Intergraph DMC. ?Updating? in this study implies the delineation of stands and estimating stand variables such as average stand height, volume density, stand volume, and tree species composition in order to identify stands which can be of current interest for thinning.
The study also includes how the aerial photo material and experience of the interpreter can influence the quality of the interpreted variables.
The aerial photo interpretations were made by both experienced and inexperienced interpreters.
Habitat preferences and reproductive success forthe threatened longhorn beetle Plagionotusdetritus
Plagionotus detritus is a threatend longhorn beetle that only exists at one site in Sweden. It is saproxylic and depending on recently dead coarse oak wood for its larval development. Trees at Djurgården, Stockholm that have been colonized by Plagionotus detritus has been studied to find out the habitat preferences of the species and to see what affects the density of beetles in a tree. The bark of some trees and wood from the breeding project at Nordens Ark has also been studied to find out what affects the species reproductive success. The reproductive success was measured in two ways, the larval mortality and the size of the hatching holes.
Artrikedom av kärlväxter i övergivna och restaurerade hagmarker : betydelsen av igenväxningsgrad och tid sedan igenväxning började
Continuously grazed grasslands have remarkably high plant species diversity. In Sweden this type of habitat has declined for the last two centuries. Changed land use has caused habitat fragmentation and loss of habitat quality. This has caused a great number of plant species to end up on the verge of extinction. To try to save this unique habitat and the species that are tied to it, lots of resources are laid on restoration of abandoned grasslands.
In this study, plant species richness of continuously grazed, abandoned and restored grasslands were related to degree of overgrowth, time since overgrowth started and rate of overgrowth.
F?RS?LJNING AV OCH INST?LLNING TILL FR?MMANDE V?XTER I TR?DG?RDSBRANSCHEN
Alien plants that have intentionally been introduced to an area for cultivation in public or
private gardens constitute the primary pathway of introduction for invasive alien species that
spread into nature. Garden owners want species that have satisfying characteristics, these
characteristics are often also linked to plant invasiveness. Thus, the horticulture industry plays
an important role by making scientifically based decisions and phasing out invasive plants and
replacing them with alternative species with satisfying characteristics, but low risks of
becoming invasive. This thesis aimed to examine the sale of and the attitudes towards alien
plants in the horticulture industry in Sweden. Alien terrestrial plants identified to have a severe
risk, high risk or potentially high risk of spreading and becoming invasive according to
ArtDatabankens assessment, were examined to see if they were for sale.
Klimatinducerade fenologiförändringar och dess effekter i näringsväven
The climate affects animal populations through several processes. These processes includereproduction, phenology and the success of hunting. By influencing the phenology of species theclimate also affects the way species interact. If a climate-induced phenology change promotes abasal species to bud earlier in the spring for example, this will affect the links to other species inthe food web due to a time lag in the tropic levels above. This dependence, that a predator has tobeing synchronous to its prey, is called the match/mismatch hypothesis (MMH).
Selecting plant species for the occasion of the 300th anniversary of Carl von Linné at Möckelsnäs :
This report was an outcome of a cooperation between ?The Visitor and Knowledge Project Carl von Linné? and SLU, the Swedish University of Agricultural Science. The aim with the cooperation was to create a garden and to suggest suitable plants for an orangery already built. All species suggested should have a documented relationship with Carl von Linné. The project is located in the southern part of Sweden at an estate named Möckelsnäs not far away from Linné?s birthplace.
Tillväxtreaktion på kvarlämnade träd i Hagners "Naturkultur" försök :
The primary goal of this study was to investigate how the radial growth of retained trees responds after thinning-from-above. The National Board of Forestry which initiated this study, was interested in whether there were differences in the growth-response between the tree species Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.). Another question of issue was if there were differences in the growth response between trees of different sizes. It is within the framework of the National Board of Forestry?s, Continuous Forests Project that these urgent questions are to be answered.