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745 Uppsatser om Threatened species - Sida 4 av 50
Vivlar på prydnadsbuskar - nya arter eller förändringar i födopreferenser?
During the last couple of years leaf-edge-cuts, typical to Otiorhynchus wingless-weevils, have been discovered on ornamental shrubs, especially Syringa vulgaris lilac and Ligustrum vulgare privet. These plant species have not earlier been attacked by wingless-weevils and because of that, the aim of this study is to see if new species of weevils have been established in Sweden or if the domestic weevils have changed their food preferences. This work also includes a literature study of known weevil species in Sweden and their host plants, and of wingless-weevil species in Europe that could be invasive here. Locations, where damage to previously named plants has been reported, have been examined. The extension and appearances of the damages have been documented in order to study if different weevil species make different types of edge-cuts.
Attityder till återintroduktion av visent i Sverige
The European bison is a species which is no longer present in the wild fauna of Sweden. Reintroduction has been proposed in several different forums. Reintroduction is an attempt to reestablish a viable population of a species in an area to which it is native. To make such an operation successful in the long run it is essential to know the attitudes of the stakeholders involved. This study has sensed the attitudes towards reintroduction of European bison to Sweden.
Kväveomsättning i gräsmark med olika artantal och artsammansättningar :
This study was carried out at the Swedish University of Agricultural Sciences, Dept. of
Agricultural Research for Northern Sweden. The aim of the study was to determine how plant species richness and diversity influence the nitrogen pools and nitrogen fluxes in the soil. Plant and soil samples from a biodiversity experiment in grasslands were used. Thirty plots with 12 grassland plant species (legumes, grasses, and non-legume herbs), combined from 1-12 species were investigated.
Landskapsplanering och konnektivitetsförbättringar inom värdetrakter i Västerbottens län :
According to the Swedish strategy for forest protection, additionally 40 000 ha productive forestland will be protected in the county of Västerbotten, between 1999 and 2010. A national project was carried out to distinguish the proportion of forest with a high biological value, in all counties. The project resulted in demarcation of small landscape areas or small ?biological value regions? (bvr), with higher concentrations of forests with conservation values and red listed species than the surroundings. In Västerbotten, 26 such bvr?s were identified and the Counties Agency and Forest Agency in Västerbotten developed a regional strategy for forest conservation to standardize the forest protection process.
Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population
The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural
forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation
has been done by the Swedish Environmental Protection Agency. In this work I have
therefore investigated how a translocation of the species succeeded after 17 years. I aimed
to study the species dispersal biology, its substrate preferences and the supply of suitable
wood on this site. The study was performed during 2012 in Pansaruddens nature reserve
close to Uppsala in Sweden, which is a spruce dominated forest.
The effect of cold stratification on germination in 28 cultural relict plant species : with the purpose of establishing germination protocols
Cultural relict plant species from the Nordic countries have been collected by the Nordic Genetic Resource Center (NordGen) for the purpose of conservation. To ensure high seed vitality in store, regular germination tests need to be conducted. It is important to get a correct viability status, but the knowledge of seed dormancy in the cultural relict plants is often poor. The objective of this study was to investigate how seed dormancy is affected by cold stratification. The study includes 31 accessions from 28 species with the purpose of establishing germination protocols.
Skyddet av arter: en jämförelse mellan amerikanska Endangered Species Act och den svenska fridlysningslagstiftningen
I dagens samhälle är skyddet av hotade och utrotningshotade arter väldigt aktuellt och kontroversiellt. Den problematik som uppstår när man vill skydda arter återfinns i alla länder, därför är det intressant att se hur andra länder valt att genomföra sitt skydd. Ett land med en omtalad och långtgående lagstiftning i detta fall är USA. Därför valde jag att genomföra en jämförelse mellan USA:s Endagered Species Act (ESA) och den Svenska fridlysningslagstiftningen. Den svenska fridlysningslagstiftningen är ingen enhetlig lagstiftning såtillvida att den har samlats upp enbart i miljöbalken (MB).
Lämpliga främmande trädslag för Kalmar och Mönsterås kommuner
This report concerns the for Sweden foreign tree species hybrid larch, hybrid aspen and poplar, and focuses on the area Kalmar and Mönsterås municipalities. The report shows that there are not only advantages with these species. The larch, the most common of the alien tree species has the greatest problems due to that its timber is difficult to sell in the area but also the Larch´s poor pulp quality and is more likely to be damaged by wildlife than the spruce is. Hybrid Aspen is much easier to sell and is used like regular aspen for match wood and textile pulp. Its disadvantage is the high cost for plants and to prevent damage from wildlife.
H?RNERVMOSSA I SANDSJ?BACKA NATURRESERVAT: Analys av h?rnervmossans invasivitet p? ljunghedens vegetationstyper
Heath star moss (Campylopus introflexus) is an alien species in Sweden and is currently classified as composing a "very high risk? of becoming invasive in the country according to SLU, and has in several parts of the world taken over large areas in a short time. The moss is characterized by its preference for disturbed and burned land, something that occurs on the heathland in the Sandsj?backa nature reserve, when burning for nature conservation purposes is carried out annually. Sandsj?backa's heathland is a valuable ecosystem and is one of the few heathlands in a favorable condition that remains in Sweden after strong reforms in modern agriculture in the last century, which led to forest succession of these cultural environments.
Härdiga palmer för skandinaviskt klimat :
The final thesis ?Hardy palms for scandinavian climate? describes the family Arecaceae both from a general point of view, and with individual descriptions of seven different species that are known for their coldtolerance. The descriptions of each species is brief and the intention has been to give an introduction to some specific species known for their hardiness.
Seperate chapters discuss topics as hardiness, pests and other problems and a short instruction for growing palms on open land in scandinavian climate. Finally a short discussion about continued research on this topic and some conclusions ends this final thesis.
Rhododendron ur undersläktet Vireya - något om dess karakteristika och användning i nordiska vinterträdgårdar :
Present essay aims to introduce the reader to central topics regarding Rhododendrons of subgenus Vireya. As a result of a donation, the Swedish University of Agricultural Sciences, received a collection of Vireya from a local amateur grower, Kurt Myllenberg. Since the subgenus Vireya is uncommon in Scandinavian horticulture, the study tries to establish conditions for successful growing.
The subgenus Vireya differ from the other Rhododendron species through mainly three characteristics: the presence of two tails, attached to each end of the seed; the ovary-style junction is tapering and the pedicels arises directly from a dome-like base and form an umbel and not a raceme. The subgenus is distributed mostly in the islands of Indonesia and New Guinea, but also from Malaysia to Nepal and in Australia.
Since Vireya species mainly grows as epiphytes in the tree canopies, they need high drainage and not too much water.
Förändringar i vegetationens sammansättning efter en våtmarksrestaurering : Changes in the vegetation composition after a wetlandrestoration
The loss of such great wetlands, which has arose in Sweden the last decades, has created a situation that threats both the function and the biological diversity within the wetlands. Many ecological niches can be found in the wetlands and it is one of the habitats where most different species exist. In the 17th Century people started to ditch damp environments, such as bogs, to create a productive cultivated ground. Further ditches were made when the forestry gave large economical profits. The wetlands were impoverished from both groundwater and nourishment, and this led to a great loss of species.In a corporation with WWF and Skogsstyrelsen in Arvika, the University of Karlstad has participated in the Laskerudproject, a hydrological restoration-project in a forest landscape.
Är vi lika dem? : en kraniestudie av hominider ur ett evolutionistiskt perspektiv
By examine plastic craniums from eight different hominids I wanted to find morfological characteristics that agreed with those of modern humans. The species that were selected had a plastic casting of its cranium in the laboratory at Gotland University. My focus was on species from the family Australopithecius and Homo and only working with their craniums. And this because the cranium and the theeth shows the most visible morfological characteristics between the different hominids. I also wanted,in a small part of the essay, to write about the differences in now living primates and humans skulls.Except from analysing the plastic castings I also studied surveys written by other scientist on the same subject.
NATURMINNENS F?RVALTNING OCH SKYDD: Inventering i V?stra G?taland
Natural monuments are natural objects with special protection due to their high natural value or cultural significance. The natural value is determined by the occurrence of signal species found on and near the natural monument. The law surrounding natural monuments has evolved a lot since the first ones were declared, and today the title natural monument can be replaced with the title tree with high conservation value. The title has come later and can sometimes overlap natural monument. Some natural monuments lack the qualities required to be classified as a natural monument or a tree with high conservation value, but have a cultural importance.
Identifiering av lek- och övervintringsområden för lax (Salmo salar) och öring (Salmo trutta) i Klarälven
Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).