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957 Uppsatser om Forest ecosystem - Sida 45 av 64

Syns vi - finns vi !? : marknadsföringsstrategier för Svenska FSC

A couple of hundred years ago half of the earth?s surface was covered by forest. Today, only half remains and every year an area the size of Nepal is disappearing. Deforestation, together with the burning of fossil fuels, is also one of the reasons for the increasing greenhouse effect. Another relatively unknown problem for the world?s forests is the trade with illegally harvested timber.

Återväxt av blåbär (Vaccinium myrtillus L.) efter ångbehandling : orsaker till effektiv kontroll

Steam was used as a site preparation method to eliminate unwanted bilberry (Vaccinium myrtillus L.) in the boreal forest. The efficiency of steam to suppress bilberry was compared with prescribed burning and cutting the bilberry. Different combinations of steaming and/or cutting the bilberry were set up to investigate in which way steaming and cutting influenced the sprouting and regrowth of bilberry. The regrowth of the bilberry vegetation was monitored for 40 month. Steam was most efficient in suppressing bilberry.

Ekosystembaserad biomimik : hantering av klimatförändringar med hållbar design

Inom hållbar design har man under senare år börjat härma naturen för att hitta nya lösningar på människans problem. Naturens ekosystem fungerar som praktiska modeller för kretsloppsfungerande miljöer där energi och material tas om hand ? precis som visionen för den hållbara staden. Genom att dels förstå ekosystemets uppbyggnad, dels övergången från ekologi till design, kan man efterlikna ekosystem i den urbana miljön. Designstrategin biomimik är en tillämpning av detta förhållningssätt, där man efterliknar naturens processer i arkitektur.

Bakteriell produktion i humösa istäckta sjöar i norra Sverige

The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.

Källor i Lagga, en uppländsk slättbygd : Geografisk och geologisk påverkan påkällvattens egenskaper

For centuries, springs have played a significant role in our society as water supplies, reasons for where to settle down, and in folklore. There are different reasons why and where a spring forms, e.g. in what kind of soil it has its outflow. Geographic and geochemical surroundings have an influence on spring-water quality.For this project some of the springs in the Lagga perish, Knivsta municipality, Sweden, were selected for a closer study. Water samples were collected from springs for analysis.

Stubbskörd : från modell till verklighet

In the near future we need to reduce the greenhouse gas emissions significantly for the benefit of the environment around us. The European Union has de-manded a variety of climate and energy goals to be achieved by year 2020, the ?20-20-20? targets. With these aims, The European Union means that we must reduce our emissions from fossil fuels and instead increase our renewable fuels. With stump harvest in the forest it?s possible to increase the use of renewable fuels and reduce our emissions from fossil fuels.

Lokalisering av sågverk i Västerbotten : en jämförelse mellan två alternativ

The number of sawmills in Sweden has decreased dramatically since the 1980s and the trend looks set to continue. The sawmills that are left instead becomes larger and are situated farther apart. In northern Sweden, they are concentrated along the coastline.In our study, we compared conditions for running a sawmill in inland areas and coastal areas and looked at what factors have the greatest impact on the profitability of the sawmill in northern Sweden.We chose to compare different locals conditions for a sawmill that only sawn pine timber and had an annual raw material requirements of 300 000 m3ub per year. By analyzing the kNN-data from the Swedish National Forest Inventory we have taken out the size of the timber volume at each site and its catchment. We have also looked at possible competitors in the areas that may affect the purchase price of the commodity.

Matematik i förskolan : Hur arbetar pedagoger med matematik utomhus på förskolor med olika pedagogiska inriktningar (traditionell, i ur och skur och Reggio Emilia)?

In this essay, I have interviewed four pedagogues from three preschools whit different pedagogical purposes. The purpose was to find out how they work with mathematics outdoor. In addition to interviews, I have conducted observations at each preschool. The different preschools are one traditional, one Reggio Emilia and one ?all weather? (Friluftsfrämjandet) preschool.

En vindkraftparks inverkan på Gävle Energis elnät

The effects from a planned wind farm on the grid utility Gävle Energis electrical grid have been studied. The wind farm is planned to be built in the forest 15 km north of Gävle and will have 23 turbines with rated power from 2 to 2.5 MW, resulting in a total installed power between 46 MW and 57.5 MW. The grid connection will be made at 70 kV. The aim of the analysis was to determine what effects the wind farm would have on the power grid in the form of electrical disturbances (flicker etc.), need for new investment and raised operational cost. To allow the connection of the wind farm technical solutions (new lines, power stations and grid reinforcements) have been constructed.

Grooming behaviour in the Red-tailed guenon

The behaviour of the red-tailed guenon (Cercopithecus ascanius) was studied over the course of nine days in the Sabaringo forest surrounding Kichwa Tembo Tented Camp near the Masai Mara National Reserve, Kenya. A focal animal instantaneous sampling method with a one minute interval was used to record the behaviours of the monkeys for approximately 12 hours a day, the day being divided into six shifts á two hours. This method has proven successful in earlier studies of red-tails in this area. The study subjects included both lactating and non-lactating females, juveniles and on some occasions the resident male. The purpose of this study was to examine the grooming behaviour of red-tailed guenons and whether or not the occurrence of grooming varies depending on monkey type (lactating or non-lactating) and time of day.

Utveckling av en diameterklassmodell för grandominerade bestånd i Sverige :

Growth models are very useful tools for forestry to predict growth and yield. With growth models and optimising tools you can manage forest stands in a way that maximize benefit and income. There are three major types of growth models. Stand models; stage structured models and single-tree models. The most advanced models give the most accurate forecasts.

pH-sensitivity in boreal streams ? the influence of landscape characteristics

The goal of the society to increase the proportion of renewable energy has led to an increased demand of bioenergy e.g. forest biomass. However, there are concerns that removal of biomass will lead to decreased base cation concentrations in the soils and acidification of streams. In order to find in which types of landscape removal of branches and tops could have such negative effects, this study aims to analyse the relations between pH-sensitivity and landscape variables in the Bothnia Bay water district. GIS and digital geographical data were used to analyse the landscape in subcatchments.

Potential för energiklippdrivare i Skåne : markägarintresse, råvarutillgång & ekonomi

As the Swedish governments long term goals include a reduction of fossil fuel dependency, increasing pressure is placed upon energy companies to create and develop new solutions for renewable energy. The following case study was done in collaboration with the company Sydved Energileveranser AB and one of their contractors, Enarssons Skogsentreprenad AB. The objective of the study is to examine the bioenergy situation in region of Skåne and evaluate the potential solutions in the region for a forest-fuel assortment, based on a bioenergy-cutting-system. As a part of this study I have compared ordinary manual cuttings done with a chain saw and cuttings made using the new ?bio- energy cutting system?. The cuttings made under both systems were tested in areas near agricultural fields or pasture land in order to maintain an open landscape.

Skogsägarföreningarnas utveckling efter krisen i slutet på 1970-talet : en analys av förändringar och trender

De första skogsägarföreningarna bildades under 1910- och 1920-talen för att i första hand främja en bättre skötsel av böndernas skogar. Under skogsägarföreningarnas snart hundraåriga historia har deras roll sedan förändrats. På grund av skogsindustrins starka ställning gentemot bönderna kom virkesförmedlingen ganska snart få en viktig roll i föreningarna.Det var dock först genom andra världskrigets brännvedshantering som skogsägarföreningarna kunde nå en större del av landets bönder och skogsägare. När skogsägarrörelsen växte och blev allt större kom tanken om att en egen industri i föreningarnas regi skulle förstärka skogsägarnas position på virkesmarknaden ytterligare. Brist på kapital gjorde dock att en industrisatsning drog ut på tiden.

Bevarande av hotade epifytiska lavar och vedsvampar i Norrbottens län : rödlistan som verktyg i praktisk naturvård

Många arter påverkas idag negativt av skogsbruket. Detta visar sig dels i ett växande antal arter på den svenska Rödlistan. I Norrbottens län är idag närmare 500 skogslevande arter rödlistade, och dessa är fördelade över flera olika organismgrupper. Det stora antalet rödlistade arter i skog innebär att det är svårt att direkt utifrån Rödlistan utforma effektiva naturvårdsåtgärder samt generell hänsyn inom skogsbruket. Genom att sammanställa och strukturera information om de rödlistade arternas krav på livsmiljö och hotsituation kan Rödlistan som verktyg utvecklas.

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