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487 Uppsatser om Soil masses - Sida 25 av 33

Virkesgripen, ett geometriskt verktyg :

The aim of this study was to investigate and describe conceptions that been used when people talks about grapples and to put together parameters that the customers sees as important when they chose a grapple from Hultdins. Every year Hultdins manufacturer and sells about 3500 grapples around the world. With so many users its difficult to oblige everyone. To get an apprehension of what kind of grapple the operators wanted a formula with 18 questions was made. For the interviews 20 forestmachineoperators were choicest who had experience from Hultdins grapples, a lot of them also had experience from other grappleproducers and constructions. The study showed that it is the durability the users give priority to.

LIDAR-analys av flygsanddyner i Västerbottens inland : Har dynmorfologi bildad under tidigare interstadialer bevarats i landskapet?

The aim of this study was to map the prevalence of aeolian sand dunes in Västerbotten, northern Sweden to find dunes formed during earlier deglaciation phases, which was then preserved in cold-based conditions during the youngest stadial of the Weichselian glaciation. These preserved dunes were expected to be covered by a layer of till and have a rather faint morphology compared to dunes formed during the Holocene. Consequently, high resolution LIDAR-derived images from the Swedish mapping, cadastral and land registration authority (Lantmäteriet) was used to detect the dunes throughout an area covering most of Västerbotten, above the highest coastline and below the mountain range. The analysis resulted in several new findings of aeolian dunes compared to the findings in the quaternary soil map created by the Geological Survey of Sweden. Despite the fact some of the dunes at the LIDAR-derived image had a strange faint appearance, it was quickly evident during the fieldwork that the aeolian sand was not covered by till on any of the dunes visited.

Silver och vismut i plaster och färger : Källor till förhöjda halter i slam?

Chemical substances are spread diffusely and uncontrollably as a result of the increased consumption of goods. REVAQ is a certification system that works to reduce the flow of hazardous substances to Swedish treatment plants and to create a sustainable nutrient recycling. According to REVAQ, the yearly accumulating rate of metals should not exceed 0.2% in soil per year. Silver and bismuth are two metals that do not fulfill this requirement. The silver concentration in sludge decreased during the last decade, however the last few years, it has leveled off.

Pottaskeframställning och tjärbränning i Femsjö socken från år 1700 till 1900 :

Femsjö is a small parish situated in Hylte municipality, Växjö diocese. The parish has a total area of 8230 ha of which 5000 ha are covered with forest. There have not been any large industries in the parish offering work opportunities for the inhabitants, so they have had to generate income from their land and the forest. Instead of going to the bank to get a bank loan the people of Femsjö parish went out in to the forest and harvested trees for timber and extra cash revenue. Production of pine tar and potash were two other ways that the residents of Femsjö parish could earn extra money for the household in order to keep starvation away.

Säsongsvis avverkning : det operativa traktvalets påverkan på den säsongsmässiga uthålligheten i ett bolagsdistrikts traktbank

Due to soft grounds in combination with seasonal variation in soil humidity, there is a lack of stands that are possible to cut during spring and autumn in some geographical regions. For Holmen Skog this sometimes means that a large proportion of the contracted private forest is cut during the winter when the ground is frozen. One consequence of this is that the proportion of winter stands in the stand bank of own forest increases while spring and autumn stands becomes a scarcity. This in combination with milder winters, especially when there is a long period of reduced bearing capacity in spring or autumn, means that the situation rapidly can become critical. The overall goal with this study was to generate basic data for decision support in the work to achieve a sustainable distribution between own forest and contracted private forest in the stand bank. The study took place at Holmen Skog, district of Umeå, during autumn 2007 and was based on interviews and an analysis of harvest planning and delivery data. The study showed that there is a problem with how the cutting is distributed between own and contracted private forest during the year and that it foremost is the proportion of winter thinning of own forest that has increased in the stand bank.

Trädplantering i stadsmiljö : exempel i Uppsala och Stockholm

Syftet med denna uppsats är att undersöka hur olika potentiellt skadliga faktorer påverkar nyetablerade stadsträd. För att göra detta utvecklas en metod för inventering av träd och ståndort, som sedan appliceras på ett urval på 94 stadsträd fördelade på 11 anläggningar i Uppsala och Stockholm. Faktorerna som framkom som resultatet av studien jämförs med skadliga och gynnsamma faktorer enligt uppgifter från trädexperter och litteratur. Uppsatsen inleds med en beskrivning av stadsträds situation idag och historiskt, samt nuvarande kunskapsläge. Därefter följer ett metodkapitel som beskriver metodutvecklingen. Metoden bygger på inventering och analys av ett antal punkter. Exempelvis behandlas vilken information stamomfång kan ge och hur det inventerats under rubriken Stamomfång.

Effekt av överlast på förstärkt jord : FEM- analys för att visa överlastens verkningsgrad på krypsättningar i kalkcementpelarförstärkt lös jord

Applicering av överlast på kalkcementförstärkta jordar är ofta förekommande idag, forskning indikerar dock på att överlasten här, inte ger samma effekt som på oförstärkta jordar. Med grund i uppmätta värden i fält, visas i denna rapport, sättningsdifferenser mellan att använda överlast jämfört med att endast applicera brukslast. Resultat av analyserna visar på sättningsbeteende observerat i fält. Om erforderlig liggtid för brukslast finns, uppstår endast små sättningsdifferenser mellan att använda överlast eller inte.Genom att utföra sensitivitetsanalys i FEM- programvaran PLAXIS studeras kryputvecklingen i den förstärkta jorden. Effekten av att applicera en överlast visas för krypsättningar över lång tid.Inget resultat från de numeriska FEM- analyserna visade att märkbart gynnsam effekt uppstår på grund av överlastens applicering, med avseende på krypsättningar.De numeriska analyserna utförs i 2 och 3 dimensioner för att belysa effekt av förenkling av ett lastfall som inte uppfyller krav för oförstärkta jordar i plant töjningstillstånd.Utöver detta ges efter en litteraturstudie, förslag på hur vissa indataparametrar kan utvärderas från empiriska relationer.

Olika typer av täckning och samodling och dess påverkan på antalet skadegörare i en Pak choi odling :

The purpose of this report is to examine the possibilities to decrease the number of insects and other pathogens in a crop of pak choi (Brassica rapa), grown with different types of cover and living mulches. Included in the report is a study of literature where amongst others, a summary on the vegetable pak choi and theories of living mulches and different kind of covers are to be found. To examine the amount of predators in the field, traps were used. During the autumn 2002 the tests were conducted in Alnarp. The pak choi and the living mulches were planted/sawn at the same time, the different covers were also applied at this time. The total experiment was divided into six different treatments (plus control) of which three were with covers and three were with living mulches. Once a week the number of leaves, the height and damages were read on ten of the plants from each parcel.

Fosforförluster från lantbruket och dess bidrag till övergödning av sjöar och vattendrag i Växjö kommun

The possibility for plants to utilize phosphorus in soil is a prerequisite for conducting agricultural production, both small scale and professional. Spreading of phosphorus fertilizers and manure is therefore seen as a necessity in today's agriculture in order to achieve high yield. Manure management, livestock farming and manure storage could contribute to the eutrophication of lakes and rivers. For instance, when the ground becomes saturated, phosphorus leakage could be seen in surface runoff or in point sources resulting from inadequate manure storage management.In the municipality of Växjö there is still many bodies of water that do not reach the Swedish environmental water quality standard of "good ecological status". This thesis has therefore analyzed the manure management and storage on agricultural farms which may have contributed to eutrophication in the municipality.The method for this thesis was a literature study, a questionnaire survey with 820 receivers and a summary of issued inspection reports from 2013.The results highlight the ways in which agriculture may have contributed to the eutrophication of lakes and streams in the municipality of Växjö.

Do retention trees affect the composition of ectomycorrhizal fungi? : a comparison between clear-cuts areas with and without retention trees in pine forests

Under det senaste årshundradet har de svenska skogarna genomgått en omfattande förvandling, från mer eller mindre naturligt dynamiska till hårt brukade skogar bestående av monokulturer av tall eller gran. Denna förändring har lett till en minskning av den biologiska mångfalden, att många arter som är beroende av skog har minskat radikalt och hotas av utrotning. Som ett försök att främja variation, biologisk mångfald i allmänhet och förhindra minskningen av rödlistade skogsarter introducerades i början av 90-talet en viss naturvårdshänsyn i brukade skogar. I den här studien utvärderas den påverkan som kalavverkning har och den betydelse hänsynsträd har på artsammansättningen och förekomsten av ektomykorrhizasvampar (EMF) under de första 20 åren efter kalavverkning. Studien utfördes genom extrahering och identifiering av svamp-DNA från jordprover tagna på kalavverkade ytor, nära hänsynsträd och i gammal skog i ett begränsat geografiskt område i norra Sverige.

Marknaden för skogsvårdstjänster : en undersökning bland privata markägare inom en region i Värmland

This work broadly illuminates the conditions for increasing the commissions of forestry services within the whole, or parts of, the western regions of Stora Enso?s operating area. Through a questionnaire, a survey was made examining whether the owners of the forests themselves do the forestry on their woodlands. This foremost concerns the pre-commercial thinning, but also planting and soil scarification. The survey also shows who are buying the most part of their forestry services and who are carrying it out themselves.

Vattensork och åkersork - skadegörare i svensk fruktodling

There are two species of voles that cause damage in Swedish fruit production: the water vole (Arvicola terrestris) and the field vole (Microtus agrestis). Both species make the most damage during the winter season. The water vole makes subterranean burrows and cause serious damage by gnawing on the tree roots. The field vole seldom makes burrows and gnaws the bark at the base of the tree trunk. In recent years there have been several reports about increasing vole damage.

Identifiering av deponerat material i en deponi samt metodikförslag för upprättande av vattenbalans.

Högbytorp is Ragn-Sells? largest waste facility and it is located north of Stockholm. There is an old landfill still in use, but at the end of this year it will be closed. The waste deposited on the landfill can, through decomposition, give rise to a large amount of methane gas, which is an energy rich gas that can be used for heat and electricity production. To receive a relatively large amount of gas, the decomposition requires a high moisture content in the waste.

Påverkan från den förväntade klimatförändringen på tillväxten i norra Sveriges skogar : En litteraturanalys

This is a literature review of how the climate change affects the forest growth innorthern Sweden. The temperature will rise about 5 °C with the largest increase in thewinter season (December - February) and the CO2level in the atmosphere is expected tobe doubled. Precipitation patterns will change and increase with 25-35 % and theprecipitation will be in form of rain rather than snow. Today the forests in northernSweden are entirely dominated by coniferous stands. This may shift with the climatechange and results in a larger number of deciduous trees, preferably birch will becomestronger and grow better and faster.

Nya träd för stadsmiljö

Trees in urban environment are exposed to extreme conditions, foremost the ones that grow in the hard packed soil along our streets. They are also exposed to damaging insects and fungal diseases both local and new ones spreading from South Europe. The global warming with warmer temperatures provides a longer growing season, making it easier for insects and fungus to establish a habitat. Based on these facts new tree species need to be available for future urban plantings.To determine what these trees would be an interview study began. Six people were selected who have experience in the field of urban environment planting.

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