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437 Uppsatser om Tree rings - Sida 25 av 30

Hållbar utveckling i svensk planeringspraktik : en diskussion kring förtätning och andra ambitioner

If one looks at physical planning in Sweden today one can see that while talking about densification of existing development, reduced emissions and careful use of important land, urban sprawl is a fact with development of sheer residential districts in the urban edges and shopping malls in each and every municipality. As sustainable development is an essential goal for physical planning to strive towards, it is worth questioning if the direction of today?s planning will lead to the goal. A sustainable development can be seen as an obvious to goal aim at. In reality the aim means a hard and complex work.

Mortalitet av bok i Biskopstorp och Frodeparken naturreservat, Halland :

The aim with this study was to investigate mortality in older respectively younger beech stands (Fagus sylvatica), the different types of dead wood in the forest and the availability of coarse woody debris (CWD). The research was carried out in previously managed and seminatural stands in Biskopstorp and Frodeparken, located north of Halinstad in Halland,Sweden. Data were collected from 22 stands with at least 50 % beech and with a minimum age of 5 1 years, ranging in size from 0,67 to 19,9 ha. A transect was placed in each stand, in which the diaineter on both dead and living trees with a minimum diameter of 50 mm was recorded. On seven to 13 dead trees, depending on the size of each stand, decomposition stage, primary and secondary cause of death, amount of fungi and the type of the dead wood was noted.

Nitrogen fixation among boreal feather mosses along a clear-cut chronosequence

The Swedish boreal forests are limited by nitrogen (N) availability. While biological N2 fixation by cyanobacteria hosted by pleurocarpous feather mosses are important sources of N input to natural boreal forest ecosystems, little is known about the patterns of N2 fixation in silvicultural systems. This study investigates the biological N2 fixation rates of two boreal feather moss species (Pleurozium schreberi and Hylocomium splendens) along a chronosequence from clear-cut to mature forest, as well as the vegetation characteristics along the chronosequence. Measurements and samples were collected from 32 forest sites that were classified into four age classes (clear-cut, pre-commercially thinned, thinned and mature forest). The sites were located near the city of Arvidsjaur in northern Sweden.

Försäljning av närvärme :

To provide our company a new business opportunity I have in this essay examined the economical possibilities to sell energy. I have chosen to do a case study on my own farm in this essay. The farm is focused to cropping and also have some properties for hire. The farm is situated in the village of Fjelie and that?s where the opportunity for selling heat are. Fjelie has about forty houses. The idea is to build a plant where straw is being used as fuel.

Indirekta effekter på marklavars abundans och diversitet vid ökad kvävehalt i marken : en jämförelse mellan opåverkad och lågintensivt brukad mark

Lichens are adapted to bright and sparse forests on oligotrophic ground. Due to a slow growth rate and high light demand lichens will suffer from competition in eutrophic environments. Therefore, lichens have disappeared from managed forests where the forest industry has increased the productivity. A reduced abundance of lichens will affect both biodiversity of the forest and the reindeer winter graze lands. It is important to understand how and for how long fertilization affects the abundance and diversity of lichens in order to protect lichen rich ecosystems. We have registered the biomass and number of lichen species in eight plots (four nitrogen rich and four nitrogen deficient) and compared fertilized Sami settlements with their oligotrophic surroundings in the nature reserves of Tjeggelvas.

Naturvårdsrestriktioners effekter på brukandet av ädellövskogen i Skåne :

Restrictions in nature conservations are increasing the influence of forest management. Nobel broadleaved forests are more influenced than other forests, because they are considered to be more valuable than other forest types in Skåne. There has been a lack of knowledge about the amount that is set-aside for nature conservation and what types of forest that is concerned. These are the main questions to be answered in this thesis. Moreover has the timber quality been compared between set-aside and non-set-aside areas since it affect the financial conditions for the forestry in nobel broadleved forests. The last asked question deals with the financial consequences of set-aside.

Överlevnad och tillväxt för nyplantersade barrots- och täckrotsplantor : en studie av 42 bestånd i södra Sverige

The choice between bare-rooted and containerized seedlings in southern Sweden affects the investment costs as well as growth and survival. It is important to take these differences into account when choosing seedling type for reforestation. The most important differences between the two seedling-types is that bare-rooted seedlings has open root systems whereas the roots of containerized seedlings are grown in a container which may contain water and nutrients that are available for the seedling during the first period after planting. Moreover, bare-rooted seedlings are often older which results in thicker stembase and better resistance to attacks of pine-weevil (Hylobius abietis). In order to study differences in survival and growth between bare-rooted and containerized seedlings a survey study of newly planted clearcuts in south-western Sweden was made. In the study tree seedling types was included, one bare-rooted and two containerized with different ages. The population of pine weevils was probably low during the studied period which resulted in lower pine-weevil damage than normally found in this area.

Naturvårdshänsyn i boreal bruksskog : En studie om avverkningar och avverkare i skogarna runt Saxdalen i södra Dalarna

As the past century?s technological development has progressed the Swedish boreal forests have transformed into dense, highly productive, homogenous and coniferous forests. The area around Saxdalen in Ludvika municipality has long been dominated forests which have been heavily worked since the 18th century. There are in Ludvika 119 000 hectares of productive forest land. Around 70 percent are owned by forest companies and 20 by private forest owners.

Bruka utan att förbruka - när andra intressen än ekonomin får styra

To have a forest area close to the city is of great importance for the city population?s well being. Children develop their motor skills, concentration and imagina-tion and the adults have a place to shake of the stress from work. Forest areas are used to exercise at, play in and to find a moment of peace and silence. The urban forest and the old farming pastures at Markussonvallen and Per-Isakssonvallen already has natural assets worth to preserve and a great potential to create more. The goal is to develop a forest with a variation of tree species and ground vegetation that will appeal to the human senses and different animal species such as birds, insects etc.

Isolating microorganisms from marine and marine-associated samples : a targeted search for novel natural antibiotics

The search for antibiotic compounds from the natural environment has been going on for seven decades, ever since penicillin entered the market and antibiotic treatments became routine. The evolutionary pressure put on the pathogenic microorganisms induced a rapid spreading of naturally occurring resistance genes, leaving only the option of finding new antibiotics to treat the resistant pathogens. Microorganisms have been extensively mined for their biosynthetic abilities to produce biologically active compounds. To date, more than 23 000 microbial natural products have been discovered. The Actinomycetales are ubiquitous bacteria that have been used for antibiotic discovery for more than half a century, and over 10 000 natural products have been identified from the order.

"Better a bird or a tree, than a human" : Om det undernärda barnet i ett globalt perspektiv

 Bakgrund: Vid litteraturgenomgång kunde tre kunskapsområden relaterade till barns undernäring i ett globalt perspektiv identifieras. Omfattning och åtgärder är väl utforskade ämnen, medan det finns mindre forskning gällande hälso- och sjukvårdens roll och framförallt saknas sammanställd forskning om omvårdnaden av undernärda barn i låginkomstländer. Syfte: Studiens syfte var att belysa omvårdnaden av undernärda barn i ett globalt perspektiv. Metod: Arbetet genomfördes som empirisk studie med kvalitativ ansats. Analysen av data, bestående av texter från bloggar och reseberättelser skrivna av sjuksköterskor på fältuppdrag, genomfördes stegvis, inspirerat av metoden för berättelseanalys enligt Friberg (2006) samt med stöd av omvårdnadens fyra metabegrepp (Fawcett, 2005).

Mobil kommunikation och högre tillgänglighet vid längre elavbrott : Exemplet stormen Dagmar och 4G-kommunikation inom smarta elnät

To be able to secure a safe and reliable power supply is becoming increasingly important since society depends on services and functions that need continuous power supply. The delivery rate in Swedish power supply is 99.98 % which insists on a high availability. During the past decade several storms has passed Sweden which resulted in large amount of tree felling leading to extended power outages. During these storms many socially critical activities, such as electric utility company Fortum, experienced disruption in mobile communication which affected the crisis management. This paper has investigated Swedish mobile operators? crisis management at Hi3G, Tele2 and TeliaSonera with a case study of the storm Dagmar that hit Sweden during December in 2011.

Kolbalansen vid olika skötselstrategier för skogen på Tagels fastighet.

Since the 19th century the concentration of CO2 in the atmosphere hasincreased by 40 percent as an effect of the use of fossil energy sources.Increased concentration of CO2 will likely lead to increased temperature,changes in precipitation, rising sea level and increased frequency of extremeweather like storm events. A step to reduce emissions of CO2 and mitigateclimate change, for the property of Tagel, can be to adopt new silviculturalstrategies and analyse which is the most effective. As a result of that, threescenarios was produced, business-as-usual (BAU), increased set aside landand energy. An introduction of windpower at Tagels estate (property) andeffects on carbon balance was also examined. By using the Heureka systemand LCA-analysis in this study, it showed that the scenario of increased setaside land was the most efficient way to reduce carbon dioxide (CO2)emissions for the analysed period of 100 years.

Identifiering av fel i skogliga beståndsregister med hjälp av satellitdata :

This thesis has focused on the possibility to use a satellite image method developed by Metria Mijöanalys to identify stands that are wrongly registered in Holmen Skogs database. The method is only intended for identifying stand with poor descriptions in Holmen?s database that needs to be updated and not for updating the stand information. The study area is located several km west of Hudiksvall on the borderline between Gävleborgs- och Västernorrlands län. The area is covered by a SPOT image from 2005. By which Metria Miljöanalys has made estimates of forest parameters for all stands in the area, and compared them with corresponding estimates according to the stand database.

Restoring biodiversity in degraded secondary rain forest in Sabah, Malaysia : natural regeneration of trees after restoration treatments

Many tropical rain forests has been lost or degraded as a result of human activities and environmental factors. Since the level of biodiversity is high in the tropics, maintaining these areas is of great importance. Forests like these are often assumed to benefit from forest restoration and rehabilitation. The INIKEA project area in Eastern Sabah, Malaysian Borneo, aims to improve biodiversity and/or species richness in the degraded forest through enrichment planting with indigenous species. The objective of this thesis was to evaluate how different treatments (liberation, gap-cluster planting and line planting) affect the biodiversity of natural regeneration in different forest types in the Rain forest Restoration Experiment, located in the INIKEA project area.

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