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681 Uppsatser om Species - Sida 18 av 46

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Nyckelbiotoper - urskogsrester eller kulturprodukter? : beståndshistorik i tolv nyckelbiotoper i Lycksele kommun

Since 1993 the Swedish Forestry Administration conducts a nation-wide inventory of wood-land key habitats covering all forest land in Sweden. The inventory aims at mapping and describing habitats where redlisted Species occur or can be expected to occur. According to the inventory stand history is crucial to the presence of red-listed Species. However, the current knowledge of stand history in woodland key habitats is very limited. The purpose of this work is to describe stand history in woodland key habitats, i.e. fire history, human activities - mainly cuttings - and structural changes.

Locally valued habitats, species and sites and their significance for collaborative land use planning around Manusela National Park, Central Seram Island, Moluccas, Indonesia

When new land use policies are made, opinions of stakeholders need to be taken in account, to avoid future conflicts. The motivations of commercial enterprises are often clear and easily communicated but due to inaccessibility and language barriers the indigenous people?s perspectives and needs are harder to reveal. This study therefore aims to identify Species and sites of importance for the local people in Masihulan village on Seram Island, East Indonesia. This is a first step to facilitate better integration of local people´s needs into local government decision-making processes.Researchers at the Center of International Forestry Research (CIFOR), with headquarter in Indonesia, have developed an approached called ?Multidisciplinary Landscape Assessment? that aims to assess important natural resources for local communities in tropical countries.

Bokhögstubbar i Klåveröds strövområde : utbredning, egenskaper och betydelse för rödlistade vedlevande skalbaggar

Lack of dead wood is the main cause of decaying or loss of populations for many forest Species. To increase the amount of dead wood is a prerequisite to maintain biodiversity in forests of northern Europe. In summer 2006 the recreation area Klåveröd, at Söderåsen in Skåne, Sweden, has been inventoried for high stumps (snags) of beech, (Fagus sylvatica). The result of the inventory has been compared with data of the real estate and forest management directories from the owner, region Skåne. The results have also been matched with the results from an inventory of saproxylic beetles in 2005, performed with windowtraps on selected snags both in the area and the adjacent national park Söderåsen. 594 snags were found on 747 ha.

Identifiering av gallringsbehov med hjälp av flygburen laserskanning :

Thinning is one of the most important silvicultural activities in middle aged forests, partly to minimize damages and partly because it leads to earlier harvesting revenues and increases the value of the remaining trees. There are many different indices used to describe stand density and thereby the need of thinning in forests today. Studies have shown that forest variables can be estimated with high accuracy using airborne laser scanning and it is likely that the method could also be used to estimate forest density indices. In this study, the possibility of using the forest density index ?H² to determine and map priorities for thinning operations for a forest area was examined.

Brandgravar : Yngre järnålder i Broe, Halla socken, på Gotland : en studie i olika metoder, med fokus på kremeringen

This essay concerns the osteological cremated skeletal remains from Broe, Halla parish, Gotland of  The Late Iron Age.The focus of this essay is to determine the position of the corpse on the pyre, whether the cremated bones were crushed after or prior to the cremation and if the individual was buried in the pyre. In addition the Species, age, sex and skeletal abnormalities of the bones in question will be studied.The result of the research has yielded that the cremated bones did not need to be crushed to result in the small fragment sizes. Crushing of the bones may have happened during the cremation, this conclusion has been drawn through the comparison of a pyre experiment were bone fragmentation is evident with cremated foxes, and dogs in the cremation graves from Broe. The construction of the pyre and the position of the corpse could not be determined through colouring and fragmentation of the bones.The human's were commonly buried in the pyre, and in some cases it is possible that the "grave" in fact is the remainder of a pyre. The Species found are dog, horse, cow, sheep/goat and bear.

Perfluoroalkyl substances in Arctic birds : a comparison between glaucous gulls and black guillemots from Svalbard

Perfluoroalkyl substances (PFASs) are ubiquitous in the environment today and they have been detected even in remote areas such as the Arctic. PFASs can be transported by the atmosphere and ocean currents but the transport mechanism is not fully understood. PFASs may be harmful to organisms due to their persistence in the environment, bio-accumulation potential and toxicity. Studies have shown that PFASs can cause adverse effects on the metabolism as well as the endocrine- and reproduction systems in organisms. In this study, PFASs were investigated in glaucous gull (Larus hyperboreus) (n=5) and black guillemot (Cepphus grylle) (n=4) from Svalbard.

Att beskriva upplevelsen av stadens rum :

The city is complex, multi-faceted and fascinating. The same can be said about the rooms of the city. The experience of the rooms of the city can be described in as many ways as there are individuals. The question concerned in this essay is How can you describe the rooms of the city as a phenomenon and how can you describe the experience of these rooms in general? The concepts city and room are widely understood and neither of them has a description that can be used in all situations.

Kontroll av rengöring med ATP-luminometer hos livsmedelsverksamheter med pizzaberedning i Sundbybergs kommun

This BSc thesis is a part of an initial step of a collaboration between Skansen and Kenyan Wildlife Service (KWS) and constitutes of an inventory of the Nairobi Animal Orphanage run by KWS. Animal Orphanage takes care of orphaned and injured animals arriving from throughout Kenya. The project started out as a refuge and as a temporary place for animals in need of care and help. With time it has evolved to an establishment that resembles and functions more like an animal zoo. The aim of this inventory is to focus on how the biological needs of Congo grey parrots ( Psittacus erithacus erithacus) and cheetahs (Acinonyx jubatus) are met, in terms of management and housing.

Överlevnad, tillväxt och skador i planteringar av sitkagran (Picea sitchensis) efter stormen Gudrun

Sitka spruce (Picea sitchensis (Bong.) Carr) is just like Norway spruce (Picea abies) a Species in thegenus picea. The natural range of Sitka spruce is a narrow strip along the west coast of North America. Itis the most coastal of all picea Species, and very dependent on the mild and humid climate along thepacific coast.Sitka spruce has been grown a long time in the countries around the North Sea, particularly in GreatBritain where it currently is the most important Species in British forestry. Sitka spruce has not beenplanted in Swedish forests to any large extent before the storm Gudrun in 2005. Several studies indicatethat the production of wood biomass is higher for Sitka spruce compared to Norway spruce.

Problembeteenden hos katt : orsaker och åtgärder

Under de senaste decennierna har synen på katter förändrats avsevärt. Från att ha setts som främst skadedjursbekämpare, har de nu tagit en mer framträdande roll som sällskapsdjur.Detta har medfört att deras miljö begränsats avsevärt och många katter hålls numera till största del eller enbart inomhus. Vilka konsekvenser detta fått för katten är ännu oklart. Hypotesen som låg till grund för denna litteraturstudie var att de problembeteenden som seshos dagens katter delvis beror av den stress som begränsandet av den naturliga miljön utgör. Syftet med studien var således att med hjälp av vetenskapliga artiklar klargöra vilka problembeteenden som förekommer, varför katten utvecklat dem samt hur de kan åtgärdas.

Aktiviteten hos thymidinkinas 1 i serum från hundar med juvertumörer och malignt lymfom

With the farming methods of the past century the agricultural landscape has changed. This has led to the fact that many habitats and Species have been significantly reduced. Sweden is committed to the preservation of biodiversity through various conventions and laws. In the EU's Common Agricultural Policy there are currently agro-environmental schemes, which were created as an instrument for reducing the negative impacts of agriculture on nature and environment. Within this system any farmer who perform environmental measures are financially compensated for this.

Foraging and anti-predation behavior of Thomson?s gazelles (Gazella thomsoni) and Grant?s gazelles (Gazella granti) at a waterhole

Prey Species make behavioral decisions to reduce the perceived risk of predation and the time spent vulnerable to predation. Behavioral responses to predators are for example selection of specific habitat types and the presence of predators influence individual vigilance. Furthermore, there is a variation in feeding niches with different herbivores focusing their foraging effort on different vegetation types which is also expected to affect the choice of habitat. Behavioral data on anti-predation and foraging behavior at on waterhole is collected from Thomson?s and Grant?s gazelles at Ol Pejeta Conservancy (0°00?N, 36°56?E) located in semiarid bushed grassland in Laikipia district of central Kenya.

Epiphytic lichen flora in a boreal forest chronosequence

Epifytiska lavar utgör en viktig del av floran i den boreala zonen. Några miljövariabler är kända för att styra artrikedomen och artsammansättningen av epifytiska lavar på beståndsnivå, såsom träddiversitet, beståndsålder, fuktighet och trädens barkstruktur. Skogsbränder utgör den viktigaste störningen i boreala skogar men studier på brandeffekter på epifytiska lavar är mycket få. Detta arbete undersökte artrikedomen, diversiteten och artsammansättningen av epifytiska lavar på basala delar av björkar längs en gradient av 30 skogsbeklädda öar som skiljer sig i storlek och brandhistorik i den norra boreala zonen i Sverige. Målet med studien var att undersöka hur lavfloran påverkades av östorleken och miljövariablerna längs gradienten.

Lantbrukare och rådgivare : tillsammans kan de främja biologisk mångfald.

With the farming methods of the past century the agricultural landscape has changed. This has led to the fact that many habitats and Species have been significantly reduced. Sweden is committed to the preservation of biodiversity through various conventions and laws. In the EU's Common Agricultural Policy there are currently agro-environmental schemes, which were created as an instrument for reducing the negative impacts of agriculture on nature and environment. Within this system any farmer who perform environmental measures are financially compensated for this.

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