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751 Uppsatser om Threatened species - Sida 18 av 51
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.
Analysis of Swedish accessions of Phaseolus vulgaris L. using SSR Markers
AbstractThe genetic diversity in cultural plants is considered to be threatened due to global climate change and antropogenic influence. Unknowing of future conditions for cultivation, gene banks all over the world are now trying to build up costly safety nets of species and varieties that may become highly valuable owing to their specific traits and genetic heredity. Hence, in 2002 there was a national inventory, aimed at the Swedish public, asking for seeds believed to be lost. Among the resulting collected seeds were some accessions of garden bean, Phaseolus vulgaris. The objective of this particular study was to assemble a collection of unique varieties and discard possible duplicates.
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.
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.
Motivation i praktiken - En fallstudie om vad som skapar ho g motivation hos erfarna IT-konsulter
The purpose of this study is to examine what creates motivation in the workplace of a small company with a high employee satisfaction index. The case study consists of qualitative interviews that help explain what the most important motivational factors are for the experienced IT consultants in a company that was founded by a circle of friends. The study concludes that the unique and equal pay model implicates an economic risk to the individual consultant but results in liberties, synergies and benefits. These appeal more than either self-employment or work at a larger IT consultancy that several consultants have backgrounds in. An expansion is ongoing since two years back, which threatened the culture but implicated opportunities for the individual consultants.
Södras gröna skogsbruksplaner ur ett landskapsperspektiv :
The aim of the "Green forest management plans" is to help forest owners to reach the
environmental goal of the forestry act. But are they able to do that? Is it possible to plan preservation of species on single estates? How do single-estate-plans differ from a landscape analysis and how can the landscape approach be used in operative planning? This work was initiated to give an answer to these questions.
This study was made in a landscape of 4200 ha in Östergötland county, south-eastern Sweden. A lanscape analysis was made and then compared to the Green forest management plans in the same area. The nature conservation areas (areas that were set aside to be managed with environmenatl goals) differed quite a lot between the two alternatives.
Skottbetning på granplantor i Kolmården : omfattning och påverkande faktorer
In the Kolmården area, northeast of Norrköping in south-central Sweden, it was discovered that shoots of spruce Picea abies, plants to a seemingly large extent had been browsed by deer. The area inhabits a dense red deer population, alongside with moose and roe deer, and red deer is thus suspected to cause the damage. The main purposes of this study are, however, to estimate the extent of the shoot-damage and to investigate what factors that may affect the browsing of shoots.
For each stand information was recorded about the age of the plants, area for the stand, height over the sea for the stand, site productivity, type of plants and stand-history.
The study was done in three areas: Simonstorp, Stavsjö and Valinge. At Simonstorp and Stavsjö, respectively, 10 stands were chosen for study and on Valinge six stands. In each stand, 10 plots were sampled.