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4968 Uppsatser om Tree with high conservation value - Sida 30 av 332

Stamskador i gallringsbestånd

This study was conducted on a property with a thinning machine team. The purpose was to investigate in which machine, the harvester or the forwarder, that caused most damage to the trees in six different stands. Different factors, related to the damage frequency in the stands, were checked out. For example: basal area per hectare, thinning strength, tree diameter and the rate of production. The harvester drivers were also interviewed about how, when and why stem damages occur and how to minimize them. The study stated that 4.3 percent of the trees were damaged. Out of these 88 percent was caused by the harvester and the rest, 12 percent, by the forwarder..

Ekjättars framtid : en fallstudie av gammelekar idag och i framtiden vid olika skötsel- och restaureringsscenarier i Hjulstaområdet, Enköpings kommun

This Master's thesis work was done at SLU, Uppsala, Sweden in cooperation with Upplandsstiftelsen and Uppsala County Council. The studied area is pointed out as an area for EU´s LIFE project, NATURA 2000, concerning the Scarabid beetle Osmoderma eremita. The studied area lies in an agricultural landscape rich on deciduous trees, about 15 km south of Enköping in the County of Uppland. The species is dependent on large, old, hollow trees, which are exposed to sunlight, usually oak trees in this area. I studied the area in detail concerning large old trees (>70cm ø), middle-aged oak trees and young oak trees.

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.

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.

Virkesproduktionen under 80 år i ett fältförsök i Dalarna med olika skogsskötselsystem

I Sverige är trakthyggesbruk med kalhuggning det dominerande skötselsystemetmen intresset för kalhyggesfritt skogsbruk har ökat de senaste åren. Alternativentill kalavverkning är omdiskuterade och kritiseras ofta för att inte vara lönsamma.Målet med detta examensarbete är att analysera ett långtidsförsök med olikaskogsskötselsystem och att diskutera eventuella produktionsskillnader. De fem skötselåtgärdersom undersöktes var 1) kalavverkning med plantering av gran och tall,2) naturlig föryngring under fröträd, 3) blädningsbruk, 4) dimensionsavverkningoch 5) orörd skog (referensyta). Fältförsöket ligger på Siljansfors försökspark iDalarna och anlades 1923. Alla försöksytor har en areal av 1 ha.

Attityder till design : samt studie- och yrkesvägledare

The background to this study is the government’s investment in design and the increase of design education around the country. As a future design teacher (industrialdesign) at high school/college, it is of great interest for me to look closer at student’s attitude towards design and design educations at high school.Questions that have been investigated are student´s attitude towards design; design as a concept but also as a phenomenon. How does the student counselor inform the students of the differentchoices before choosing high school?Does the students view on design correspond to what the student counselor say?What opinion does the student counselor have to the concept design as well as design in highschool? Is design just a craze or here to stay?To get answers I have made interviews with student counselors at two different schools, I have also been in contact with a student counselor on the internet. Their thoughts will clarify thesituation that the students might be in.

Uppvärmning med spannmål och trädbränslen :

This examination work brings up opportunities to invest in a construction for heating with grain or pellets on farm level. As example we have chosen Fröberga Gård which is a farm located in Östergötland outside of Söderköping. The farm`s residential buildings is to day heated with oil and electricity. The result of our investigation shows that heating with grain is the best alternative, partly because of economical issues but also because you can grow the grain on your own farm and by that you can get better economy in your seed cultivation. To grow 16 tonne of grain as is needed demand gives a insignificant increase of work. Further an advantage is that no investment in machines is needed because all the machines witch is needed already is in use on the farm. In a situation where a new investment is needed as in the case we studied, is it often profitable to invest in a integrated furnace. Because all the components are well adapted to each other, and because that gives a high efficiency. If you already own a well working furnace is it often most profitable to connect a burner to it. It is important to know that heating with grain need more work than heating with pellets, because the high contents of ash in grain. Even if you choose pellets instead of grain the calculation shows good results. Because peat is an excellent but fairly untested raw material for pelletsproduction we have chosen to watch little more on its quality and conductions. We discovered that peat has a high heating value which makes it possible to raise the heat value in pellets through mix up peat and wood. Or you can make pellets with only peat and get a pellet with high heating value. Even the calculation with peatheating shows good results..

Hygienisk kvalitet hos svensk älgfärs med avseende främst på förekomst av koagulaspositiva stafylokocker och Escherichia coli :

In this study the hygienic quality of minced moose meat was examined with regard to the prevalence of different bacteria. The methods used are described in NMKL, "Nordic Method Committee for Food". The results show that the levels of Escherichia coli and coagulase positive staphylococci in the meat are too high. The reason for this might be environmental factors, such as high temperature and humidity during the time when the carcasses are hanging and when the meat is cut up..

Tillämpning av kNN-Sverige i Södra Skogs verksamhet : behovsinventering, databearbetning och förberedelse för praktisk implementering

The digital map product kNN-Sweden contains nationwide data of the country?s forest land. The estimated forest variables are mean age, mean tree height, volume per tree species and total volume. Today Södra Skog?s assessments of timber potentials are mainly based on experience rate and subjective assumptions.

Att vinna eller försvinna när alla får varsin dator : En-till-en-satsningar och dess inverkan på delaktighet, självbild och lärande för gymnasieelever i behov av särskilt stöd

The purpose of this study was to investigate how high school students felt that the computer helped or hindered participation and self-esteem in the learning situation and if the students experienced any differences between when they had been relatively alone in using a computer compared to when everyone had their own computer. The starting point was the national one-to-one projects made to give every student access to a personal computer and how it affected students in special educational needs and previous research. The theoretical approach was based on socioculture/activity theory and theories of self-esteem. Ten high school students in grade one at a senior high school that previously had started up a one-to-one project was interviewed. The results showed that the students primarily used the computer to write and to search the Internet, but even as a alternative or compensatory tool.

Friluftslivet i det nya läraruppdraget

The aim of this essay has been to surrey the perspective of view the special education teachers have on the tree concepts of special education, compensatory-, critical and dilemma perspectiveThe questions that have been covered in this study areWhat does the concept of special education means for the special teachers? What does the concept of mathematic difficulties means for the special teachers?What does the concept of the diagnostics of dyscalculia means for the special teachers?A qualitative research method has been used to answer the questions in this essay. In the purpose to get the most out of the study..

Miljö- och hälsoskyddskontorets tillsynsarbete - ur verksamhetsövarens perspektiv

Nanofiltration is a proper way of preparation of drinking water. The process has a lot in common with reverse osmosis where a semipermeable membrane is used to separate a pure water flow from the remaining water. A pilot plant was used to ensure that nanofiltration is a suitable technology for a specific waterworks station in Glemmingebro, Ystad. The purpose was also to find out if a pH-adjustment is needed for feed water in a possible full scale plant.  In this case nanofiltration is used mainly to remove sulphate and calcium since the raw water contains concentrations of these substances which exceed the limits for potable water. It is important to receive a high recovery (RC), otherwise the deliviery of water won?t be high enough.

Ny princip för spänningsreglering i Fortum Distributions mellanspänningsnät i Stockholm.

The voltage regulation in Fortum Distributions medium voltage network in Stockholm does not work satisfactory. This results in too high distribution voltages with many customer complaints as a consequence. The reason is the model responsible for compensating for voltage drops in the distribution network. Despite several adjustments Fortum has not been able to find the source of the high voltages and has therefore appointed an investigation in the form of a thesis work.The aim of this investigation is to locate the error and to produce a proposal regarding the solution of this error using the existing system, common industrial knowledge, state of the art research and the option to use voltage readings from the different substations.The conclusion of this master thesis is that the largest contribution to the high voltage levels is made by the large compensation for distribution loses. Furthermore an additional error in the model has been found.

Variationer i normal språklig förmåga hos vuxna jämfört med neural aktivitet

Since the brain is an important prerequisite for human language there is a great interest to gain more knowledge about healthy brain activity during language mediated communication. This study examines variations in high level language ability relating to demographic factors like gender and age and relates language ability to neural activity.Eighteen individuals in ages between 22 and 64 were included and divided into groups in relation to gender and age. The material used to assess language ability was derived from Testbatteri för Bedömning av Subtila Språkstörningar (Laakso, Brunnegård, Hartelius & Ahlsén, 2000), Swedish Lexical Decision Test (Almkvist, Adveen, Henning & Tallberg, 2007) and a reading test (Högskoleprovet). The results were correlated with measured brain activity using functional Magnetic Resonance Imaging (fMRI) and language paradigms. ANOVA was applied to discover possible demographic variances in language ability as well as in brain activity.The results showed no significant differences in language ability.

Större och mindre växtätares samexistens : Möjlig interaktion och effekt på lokal biodiversitet

The purpose of this report was to investigate to which extent local presence of large herbivore mammals (Alces alces, Cervus elaphus, Capreolus capreolus, Dama dama and Sus scrofa) covaries with small rodents (Myodes glaerolus, Apodemus flavicollis and Apodemus sylvaticus? The hypothesis was that high abundance of wild ungulates would inhibit the density of small forest rodents. The data was collected during field work within FoMA (Environmental Monitoring Assessment)/SLU (Swedish University of Agricultural Science). The Ungulate dropping inventory and rodent trappings, which is the base in this report, where performed 2012 ? 2014 in Gnesta/Nyköping municipalities (G/N) with a relatively high density of wild ungulates and Vetlanda/Växjö municipalities (V/V) with relatively lower wild ungulate density.

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