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1038 Uppsatser om Signal species - Sida 23 av 70

Picea mariana ((P. Mill.) B.P.S), P. abies (L.), Pinus contorta (Dougl.) och P. sylvestris (L.) : en jämförelse av produktion och potentiell kvalitet hos försöksbestånd i Jämtlands län

Swedish forests are dominated by just two conifer species Norway spruce and Scotch pine. They are not able to achieve the highest possible production or fulfill industry demands for raw materials. The introduction of exotic conifers can potentially meet these shortcomings and present a relevant solution. This study was conducted in a block experiment with ten blocks planted in 1987 by SCA in North Sweden. The objective of the block experiment was to study if Black spruce is an appropriate alternative to Lodgepole pine, Norway spruce and Scotch pine on different site classes.

Jaummuov?rrie blomster?ng: en v?rdering av artrikedomen och dess kulturhistoriska roll

The thesis "Jaummuov?rrie Flower Meadow: An Assessment of Species Diversity and Cultural History," provides a detailed botanical examination of Jaummuov?rrie flower meadow in the Ammarn?s area, focusing on its biodiversity and cultural significance. The study aims to evaluate the species richness of the meadow and explore its role in the cultural heritage of the region. In addition to its ecological importance, the thesis delves into the cultural history of Jaummuov?rrie flower meadow, tracing its significance to the local community and traditional practices.

Parasitering på en expanderande art : har kartfjärilen undkommit sina naturliga fiender?

Warmer climate is a driving factor to species expansion northwards. Expansion to new areas can result in escape from natural enemies, resulting in reduced levels of mortality and thereby potentially increasing the rate of expansion. The most important parasitoid species attacking butterfly larvae belong to the families Tachinidae, Ichneumonidae and Braconidae. The aim of this thesis was to investigate parasitism and difference between populations in established area and newly colonized area for the European map butterfly, Araschnia levana, in order to examine if the butterfly has escaped from some natural enemies. In 1982 the first European map butterfly was observed in Sweden and has now established up to middle Småland.

När trädens rotsystem får bestämma : En intervjustudie med en grupp yrkesverksamma inom anläggning av hållbara gröna miljöer.

ABSTRACTThis pilot study examines the knowledge about tree root systems amongst five treeplanting professionals. The aim is to find out the professionals? collective knowledge ofthe nature of root systems of various trees used in green areas. Furthermore; to explorehow the professionals adapt landscaped green areas to the tree root properties in asustainable manner. Questions: Which tree species have special root properties toconsider and how do the professionals utilize this knowledge? And: How do theprofessionals in general adjust planting according to the root systems of trees in areas tocreate sustainable green environments?Interviews with the professionals were performed.

Biosensorsystem fo?r o?vervakning av vattenkvalitet

Sweden's drinking water quality is considered to be high partly due to a high quality of the raw water and a well developed sewage infrastructure. Despite this, there is water contamination that could be prevented by installation of a sophisticated early warning system. Some of the major players in the production of drinking water have already invested in different types of early warning systems to ensure drinking water of high quality. There are various forms of early warning systems where automatic monitoring of E. Coli is an interesting alternative.

Vedlevande lavar på döda grenar på levande träd i produktionsskog

Saproxylic lichens in managed forests have less substrate available than in unmanaged forests due to the shortage of dead wood. However, a suitable substrate for these lichens could be dead branches on living trees. To this date, there has not been any systematically collected data about theabundance of dead branches on living trees and the lichens growing on these branches in managed forests. The aim of this study was to see where dead branches were located on living trees of Pinus sylvestris and Picea abies, how large the surface area of these branches was and what lichens grewof wood on these branches. The study was made in Finspång, Sweden, where 11 forest stands of P.sylvestris and P.

Hundens kommunikationssignaler

This literature study summarizes the signals dogs use in intraspecific communication. The purpose is to clarify the way dogs communicate so that situations where their intentions are misjudged can be avoided. The signals are divided into olfactory, visual, auditory and tactile and every section starts with a short anatomic and physiologic description of the sense organ that is used to register the current signal type. The interspecific communication between dog and human regarding its development and function is brought up. To end with suggestions are given of how veterinary technicians in clinics can make use of knowledge about the way dogs communicate.

I människans tjänst? : en studie om relationen mellan människa och djuroffer i gravar från yngre järnåldern

By examine cremated remains from graves dated to late Iron Age I wanted to find out what sorts of animals were placed in the graves. But also to see if the animal sacrifices had any connection to the Old Norse religion. The osteological material that were analysed were from both cremated humans and animals and had been dated to Viking Age. The material is from burial ground 59 at Laxare, Boge parish on Gotland. In addition to the human remains, the material contains bones from horse, cattle, sheep/goat, pig, dog, cat, bear, birds and fish.

Skogseldens påverkan på epifytiska trädlavar på tall i relation till brandintensiteten :

Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization. The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.

Granföryngring på tallmark, hur ofta förekommer det? :

This survey was made during the summer of 2004 and the spring of 2005, on commission from the National Board of Forestry. The aim of this report was to investigate how often Norway spruce (Picea abies L. Karst), is planted on poor Scotch pine (Pinus Silvestries) sites and if it affects the yield of Norway spruce? In order to investigate this, data from 29 stands witch had a lower site index than T24 was collected. The investigated stands were situated in the southern-eastern Sweden. In 20 plots in each stand, the highest tree, age, number of seedlings, site index and tree species per stand were measured.

Poppel - en möjlighet i norra Sverige?

The countries in the European Union have agreed to increase their percentage renewable energy sources to 20 %. To reach this goal an increase of biomass production needs to be made. One way of achieving this is by using nonnative species. Poplar in Sweden produces biomass faster than the domestic trees. In the southern parts of Sweden plantations has been made with good results. In the northern parts survival is a problem that needs to be solved before plantations can be made for commercial use.

En skogshistorisk jämförelse mellan två närbelägna landskap med olika mångfald i östra Småland :

This study shows the historical development of the forests in Hornsö and Ebbegärde state forest area in eastern Småland situated in southern Sweden..

Död ved i gallrad skog och nyckelbiotoper : en jämförelse av habitatkvaliteter för vedlevande lavar och mossor

A high amount of dead wood is one of the most important prerequisites for high biodiversity on forest land in Sweden. Dead wood is most abundant in young forests, thinned forests, woodland key habitats and protected forest land. In old-growth forests most of the dead wood consists of logs and snags, whilst in managed forests a huge proportion of dead wood is made up of logging residues like stumps and FWD, fine woody debris (< 10 cm diameter). All these different types of dead wood may serve as substrates for epixylic bryophytes and lichens. However, few studies have been conducted on the relative importance of these different fractions of dead wood for the occurrence of bryophytes and lichens, especially when considering dead wood on thinned forest land.

Samverkan på svenska mötesdestinationer.

Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization. The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.

Jämförande studie av normal ERG-svar hos tre olika hundraser :

The purpose of this study was to compare normal electroretinographies (ERGs) from three different canine breeds in order to evaluate if there were any marked similarities or differences between these breeds as to ERG responses. It is known that healthy dogs from different breeds but also dogs within the same breed but in different age categories may have different appearances of their ERG responses. This may be a problem when evaluating if an ERG is normal or not from a dog within a breed not previously examined. Because of this it is important to obtain normal values for each breed and age group in order to be able to use these for later comparisons of ERGs obtained from individuals affected with various retinal diseases. In this study we have chosen to examine dogs within the three breeds: Labrador Retriever (LR), English Springer Spaniel (ESS) and Chinese Crested Dog (CCD). All of these breeds may be affected with hereditary retinal diseases such as Progressive Retinal Atrophy (PRA). It is possible that ERG-responses vary due to a number of different factors.

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