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957 Uppsatser om Tropical rain forest - Sida 41 av 64

Trädens utveckling efter att de har lämnats som naturhänsyn : tillväxt, mortalitet och strukturell förändring 6-18 år efter avverkning

Today green tree retention, together with leaving dead wood, is a common practice with the aim to reduce negative impacts on biodiversity and environment due to clear-felling. To better understand whether this conservation practice also makes a long-term difference, it is important to know what happens to these trees after harvest. Few studies have made an assessment of what happens to retention trees over a longer time period. In this study I inventoried retention trees that were left at clear-cuts six, twelve and eighteen years ago. I carried out a re-inventory of 57 retention patches (divided into free-standing tree groups, small swamp forests and edge zones) and free standing dead trees, spread over 25 previous clear-cuts in central Sweden.

Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier

Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in theevent of rainfall. An increased level of radioactivity in the plants may occur due tointerception and retention of the radionuclides. If the content of the plants is above thethreshold limit value, entire yields may have to be destroyed. In order to preventcontamination or decrease the content countermeasures can be taken. The impact of thebiomass, leaf area index (LAI) and growth stage of the plant on the interception andretention is important to know in order to decide which countermeasures to use.Weather may also be an important factor.In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley andspring oil-seed rape was studied.

En studie av utvecklingen av drivningsnettot i skogsbruket :

This master thesis consists of an investigation of the profitability per hectare in privatly owned forest land. The investigation is based on data collected from Skogsstyrelesen, Riksskogstaxeringen and Skogsforsk. During the last twenty years the prices on pulp wood and saw log have substantial decreased, but during the same time the the volumes from final felling have increased and the cost for felling has decreased, this investigation shows how the netprofit per hectARE after final felling has changed between year 1980-2005 This investigation shows that that the netprofit has stayed on a stable level during the years 1985-2005 even though prices pulp wood and saw log decreased. Much indicates that the demand of swedish pulp wood and saw log will continue to be strong or even stronger wich will give increased prices and an higher netprofit after final felling in the future.

Att uppleva naturen med alla sina sinnen : Hur undersöker och upplever förskolebarnen naturen?

AbstractThis project discusses various aspects of children's way to explore nature with their senses. Therefore I conducted a study in two preschools, one nature-oriented and another preschool. This study was carriedout usien the three metods, interviews, observations and surveys. Interview four children from each preschool, observations of each group outdoors during four different occasions and question forms to teachers. The result of the study showed that both teachers and children have a great interest in being outdoors in nature, but it is not always possible to take out all children's groups. The reason is large groups and inadequate staff.

Lekens betydelse för barns utveckling : En studie om hur skolgårdsmiljöns utformning påverkar barns leklust

The purpose of this study is to illustrate the impact on children's development around playing and how significance the formation of the schoolyards is focusing on how it inspire and calls to play within the children's. The study will also show how the youth workers experience the schoolyards and how they can incorporate the playground in their work to inspire the children's play and activities. The methods used in this study is based on both real conversations and by mail with educated youth workers and observations. The results shows that the schoolyard environment is very important for the children's play and development. The study reveals the importance of having nature like forest nearby and that the environment should be suited for everyone.

Urban dagvattenhantering med regnträdgårdar : gestaltningsförslag för Gårdsgatan i Norra Djurgårdsstaden

I Stockholm pågår i dagsläget ett stadsutvecklingsprojekt som kallas Norra Djurgårdsstaden, där visionen är att skapa en hållbar och klimatanpassad stadsdel i världsklass. Stockholms stad har valt att bland annat arbeta med olika former av ekologisk dagvattenhantering i projektet, där en av dessa former är regnträdgårdar. Syftet med denna kandidatuppsats är att ta fram ett gestaltningsförslag för hur dagvattenhanteringen kan lösas med hjälp av regnträdgårdar längs en planerad gata i Norra Djurgårdsstaden. Gestaltningsförslaget baseras på underlag av landskapsarkitektkontoret URBIO, som har erfarenhet av att arbeta med regnträdgårdar. Växter och växtbäddsmaterial är huvudsakligen valda utifrån råd från sakkunniga. För att få förståelse för regnträdgårdens funktion och uppbyggnad gjordes en litteraturstudie i arbetets inledande fas.

Prislisteoptimering för ett sågverk - Jarlträ AB :

This report is a thesis work for a B.Sc. in Forestry at the School for Forest Engineers, SLU. The work was an assignment from Jarlträ AB which is a privately owned sawmill located in southern Småland. The aim of the work was to investigate the economical result of different pricelists and how to adjust different parameters such as length correction to give an optimal result. The pricelists was examined through a computer program (SilviA). The pricelists was made in the program and after that a simulation was preformed with a selection of random sampled trees gathered from the area nearby the sawmill.

Resultat av tjugofem års mätningar av Cs-137-halter i älg i Uppsala län

At the end of April 1986 reactor number 4 of the nuclear power plant at Chernobyl explod-ed and large amounts of radioactive particles were then released into the atmosphere due to both the explosion as well as the consecutive fire of the graphite core. A cloud of radioac-tivity was spread over the northern hemisphere, including Sweden, due to the prevailing wind directions. The radioactive particles were washed out from the cloud by rain and snowfall in some areas of Sweden and deposited on the ground. The deposited radionu-clides, primarily cesium and iodine isotopes, were later absorbed into the soil and taken up by the roots of the plants. Some of these radionuclides, like 137Cs, still persist in some of the terrestrial ecosystems at relatively high concentrations which lead to contamination of the meat of moose, roe deer and wild boar even today.The two municipalities Heby and Uppsala, in the eastern part of central Sweden, experi-enced a relatively large deposition of 137Cs which resulted in high levels of 137Cs in moose and other game.

Leaf area index in Vittelaria Paradoxa parklands in Burkina Faso estimated by light interception and leaf sampling

Burkina Faso as well as most sub-Saharan African countries struggle with providing food for a fast growing population. The dominating farming system is agroforestry parklands. Agroforestry parklands can broadly be defined as areas where scattered trees occur on farmlands as a result of selective clearing. The presence of trees in crop fields may in the long term have a positive effect on the production of annual crops. It is commonly discussed, but not proven, that the presence of trees leads to increased groundwater recharge due to higher infiltration capacity of the soil.

Utvärdering av Hultdins prototyp för portabel bro (drivningsbro) :

Stronger demand has been put on forestry to show environmental considerations during harvesting. This is especially for crossings of brooks with sensitive elements and great care should be observed when they are to be crossed during harvesting by logging machines. For that reason Hultdins has constructed a portable bridge that can be used for those occasions. The bridge has been developed in accordance with wishes from SCA forest, since they have a great deal of brooks in their forests and in private forests from where they buy part of their wood supply. The aim for this report is to investigate if this portable bridge can be of interest for the forestry market. The research has been made at SCA skog in Medelpad and Norrskog in Medelpad.

Hur främjar förskollärare barns motorik i förskolan och hur viktig anser de att den är?

AbstractThis work is about children?s motor activity. You can often hear in media about sedentary children, and that one of the factors which contributed to this is computers and things like that. The main goal with this work is to find out how preschool teachers take care of children?s joy of movement and how they work to promote children?s progress of motor activity.

Kvalitetssäkring av servicelämnare för skogsbrukets arbetsmaskiner : Intervjuer och förslag till utveckling

In this study we have examined the possible quality standards and methods for applications with service workshops in the forest industry. The purpose of the methods presented here was to start the work of standarardising the maintenance service in the industry and be of use for service providers in their quality effort.The methods we used to accomplish the study were interviews and field visits together with a comprehensive literature research. Our results are presented in the form of four solution proposals: a standard based on existing SIS standards for terminology and key indicators, checklists that are filled in by mechanics with customer participation, the construction of a instructions database, and the implementation of the method 5s.We believe our suggestions can help the service providers in the four problem areas that we have identified: long term strategy, documentation, recruitment of competent technicians, and standard procedures in their operations. These improvements will be beneficial for both the service provider and the customer..

Utveckling av logistikflöde : En undersökning av införande av extern kittning av hydraulslang vid Komatsu Forest AB

Komatsu Forest AB tillverkar skogsmaskiner och aggregat. I monteringsprocessen är hydraulslangar en av komponenterna som hanteras och lagras per artikelnummer. Idag genomförs intern kittning då slangar plockas ur respektive lagerlösning mot en specifik monteringsoperation. Kittning innebär att delar och komponenter sorteras i set, så kallade kit, innan de levereras till monteringsoperationer. Genom extern kittning som utförs av leverantören kan eventuellt flödet av hydraulslang och utnyttjandet av ytan i anläggningen bli mer effektivt då kitten är färdiga när de anländer till anläggningen. Syftet med arbetet är att identifiera det mest produktiva och kostnadseffektiva arbetssättet gällande hantering av hydraulslangar från beställning till montage på maskin.

Utvärdering av traktplanering på Holmen Skog

This study has been performed with the help of forest machine operators in order to improve the forestry planning at Holmen Skog Örnsköldsvik-region. For Holmen Skog forestry planning is basic for a successful forestry. In a survey I have investigated what can be improved in some areas that are planned for harvesting. The result of the investigation will be used to support the machine operators as much as possible. The study has generated 49.5 % of responses and because of this low response rate, no clear conclusions to anyone else except the responding machine operators can be drawn. It has been proved that there are some details in the forestry planning system that are inadequate, such as marked routs for trails, tractor paths and buffer zones against streams. The quality of forestry planning varies greatly between different locations, as much as 50 % of the responding machine operators thought so. Over 40 % of the responding machine operators claim that the information from Holmen is insufficient. One thing that would improve the forestry planning within Holmen would be to educate all forestry planners and then do continuous follow-ups..

Miljöhänsyn vid offentlig upphandling :

One of the biggest challenges in the human history is to prevent environmental pollution. Everybody has an indirect or direct influence on the environment through his or her consumption. The stakeholders are not just interested in price and quality, they are also interested in the circumstances of production and how this affects the environment. By taking environmental concern in public procurement it is possible to speed up the environmental adjustment of services and products. Environmental awareness has become more and more self evident in the environmental work.

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