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116 Uppsatser om Self regeneration - Sida 7 av 8

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was studied on 12 sites in coastal areas of northern Sweden. On each site, sample plots were placed in adjacent Norway spruce and Scots pine stands with similar ages in between. Basal area, tree height, Site Index, volume production, simulated maximum mean annual increment (MAImax) and tree vitality were compared for the two species. Average basal area at the time of measurement was 30.4% larger for Scots pine stands than for Norway spruce stands. The difference between the two species in basal area increment during the last 10 years was related to stand age.

Skogsskötsel för att minimera stormfällning över järnväg :

The society of today is dependent of secure transports and deliveries of electrical power. Interruptions in different activities because of fallen trees cost a great deal of money in form of reparations and claimed damages for transport companies and electrical suppliers. Fallen trees along some railway sections are a severe problem. For instance, to repair the damages of the storm of week 5 year 2002, costed 2 800 000 SEK for the line region of Hässleholm. Today, the Banverket railroad company has no norms in general for how close to the railway the forest is allowed to grow.

Askåterföring i Jämtland : biobränslets och askans innehåll av tungmetaller relaterat till markernas geokemi

Using biofuels from regeneration cuttings is becoming more common in Sweden. Ash from the combustion of biofuels contains many valuable nutrients and base cations. The Swedish Forest Agency recommends that ash should be recycled to clearings where biofuels have been removed, to avoid future impoverishment of Swedish woodlands. In Jämtland, in northern Sweden, a large quantity of biofuels are taken out from cuttings but ash recycling has not yet been tried. The aim of this thesis was to examine the conditions for ash recycling in Jämtland regarding to soil chemistry and heavy metal content in soil and biofuels.

Daily rests of wild boar Sus scrofa sows in southern Sweden

For a few decades, the wild boars are established over large areas in southern and centralSweden. Where they cause problems in terms of damage to crops in the agriculturelandscape, where rooting, browsing and trampling, but also damage to the crop when wildboars chosen daily rest in the cultivated fields. Along with the growing number of wildboars the rate of car accident with wild boars has also increased.Here I examined the daily rests of wild boar (Sus scrofa) sows in southern Sweden, todetermine the factors which the wild boars sows choose for daily rest. By determining whatfactors are important in this selection of daily rests, we may be able to make managementmeasures to reduce the damage wild boars make in the agriculture landscape by attractingthem to places where they do less economic damage and accidents on roads.In this study I have examined 123 daily rest positions from 14 different individual wildboar sows fitted with GPS collared in Southern Sweden, Skåne County in Christinehof,Högestad Kronovalls estate. Data was collared over the years 2004-2006 during the periodfrom June 1 to September 30.

Skogssådd med tall och gran : effekter av fröegenskaper och skärm/hygge på plantbildning, överlevnad och tillväxt de två första åren efter sådd

Over the past few years the Swedish forestry industry has become increasing interested in direct seeding. Although, in practice, this interest has been restricted to pine seed, the knowledge and techniques that have been developed for pine seeding can readily be transferred to spruce. Direct seeding is a method that is of interest to the forestry industry since it can lead to lower regeneration costs, denser stands and better root development than the more conventional planting method. This study evaluated experiments that focused on direct seeding of spruce in the northern Sweden. Skogforsk set-up the experiments in Gideå and Sävar in 2003.

Plantinventering och plantkontroll med digitala bilder från helikopter :

This study was carried out as a commission from Holmen Skog, district ?Egen skog? in Norrköping. During October 2006 several stands were inventoried by aerial photos from helicopter. The stands were those for which the next action proposed was plant inventory or plant check. The photos were interpreted and the number of stems was calculated.

Renens fejskador på tall- och contortaplanteringar inom Malå samebys höst- och vinterbetesområden :

The effects of Reindeer mechanical damages on the planted regeneration of Pinus sylvestris and Pinus contorta. Semi-domesticated reindeer can damage young trees. In late winter reindeer rub their antlers against young trees. The aim of this study was to quantify those damages. This study covered planted objects from three different areas in northeastern Sweden.

Är förekomst av knäckesjuka i tallföryngringar mindre på stora naturvårdsaspar än på aspsly?

Pine twisting rust (Melampsora pinitorqua) is a parasitic rust fungus found all across Sweden causing damage resulting in lower quality and reduced tree growth in pine stands. In Sweden, the fungus is dependent on two alternate hosts; European aspen (Populus tremula) and Scots pine (Pinus sylvestris). Pine twisting rust has five different spore stages, two of them (uredinio- and teliospores) on the leaves of aspen. Injures on aspen caused by pine twisting rust is not extensive. On the other hand, when it infects the annual shoots of Scots pine it often results in a bent steam or even a top shoot breakage.

Stadsförnyelse i waterfrontområden - en jämförelse mellan Norra Älvstranden i Göteborg och HafenCity i Hamburg

Några stadier i utvecklingen för waterfrontområden kan identifieras; strategiskuppväxt, industrialisering, avindustrialisering och förnyelse. Ofta är förändringar iekonomiska förhållanden och ny teknologisk utveckling de primära krafterna somgett upphov till nya rumsliga och funktionella relationer mellan hamnen och staden.I en utveckling som har tilltagit sedan andra världskriget flyttar industri,transportanläggningar och hamnar bort från centrala stadslägen. Denna flytt är oftaden utlösande faktorn för waterfrontförnyelse; övergiven industrimark nära stadenskärna frigörs och kan då omvandlas till andra ändamål. I processen för att förändrawaterfrontområden måste flera olika flöden samverka, däribland ekonomiska,politiska, kulturella och ekologiska processer. Ett avdelande vattenparti i en stadkan fungera som en styrka som skapar tillväxt men också som en barriär som skaparavstånd och hindrar uppbyggnaden av en sammanhållen stad.Syftet med denna uppsats är att översiktligt undersöka relationerna mellanwaterfrontområden och dess stad och mer specifikt att undersöka hur detta ser ut itvå waterfrontprojekt i två städer i Europa; Norra Älvstranden i Göteborg ochHafenCity i Hamburg.

Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna

In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time. The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.

Viltets inverkan på vegetationsutvecklingen i en Sydsvensk skogsföryngring :

Herbivore impact on the Swedish forest has under a long time been a common subject of debate. There are many different opinions depending on what direction the forest owner has with his/her forest. Populations of moose and roe deer have increased significantly in Sweden during the last decades. The purpose of this study is to get a full picture of the herbivore impact on the regeneration areas. The field work was done once a year for seven years (1999?2005).

Bosättning, agrarkris och fäbodväsende : vegetations- och markanvändningshistoria i Läde, Dalarna

By using pollen analysis, 14C-dating and historical sources, I studied the history of vegetation and land use at an abandoned forest settlement near the Lade summer farms in the parish of Mora, Dalama. The aim of this paper is to investigate the agricultural establishment and development, the effects of this on forest vegetation, and the origin and development of summer farming. The analysis of pollen in a peat core revealed that a settlement was established at Lade around 1000 AD. Cereal cultivation, hay-making on the mire and extensive forest grazing were intro-duced as a complete agricultural system. Pollen analysis and the presence of ancient fields suggests that cultivation took place on permanent fields. Barley was the main crop, but rye and hops/hemp were also grown at the settlement.

Uran i dricksvatten : litteraturstudie om reningsmetoder samt pilotförsök med jonbytesteknik

Uranium (U) is a naturally occurring component in bedrock and under the "right" conditions it can dissolve and move into the ground water. Since many people in Sweden depend on drilled wells as their main drinking water supply, they may be exposed to the uranium in the water. Radioactive radiation is not the major concern associated with naturally occurring uranium. It is rather the chemical properties of uranium that make it a potential danger to human health. Uranium is proven to have toxic effects with respect to the functioning of the kidneys.

Dikesrensning och skyddsdikning : en fältstudie och utredning av behov i södra Sverige

During the 20th century a significant proportion (about 15 %) of the peat-covered wetlands in Sweden were drained to improve forest productivity. Area wise, most of the forest drainage was done in northern Sweden, but relatively speaking a larger part of the wetlands have been drained in the southern parts of the country. Most often, the forest drainage resulted in increased forest growth, but failures were not unusual, and harmful effects, e.g. on species richness, have been a common cause for draining. Ditch cleaning is necessary for maintaining the ditches in good condition.

Tree species traits response to different canopy cover for 34 tree species in an enrichment planted tropical secondary rain forest in Sabah, Malaysia

Tropical rain forests only cover around six percent of the world?s land area and contain around 70 % of the world´s animals and plants. Tropical rainforests have been, and still are, negatively affected by human activities. These activities lead to forest degradation which has negative impacts on production and biodiversity. Between 1970-1980 forests in Borneo, Sabah, Malaysia, was subjected to intense logging.

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