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791 Uppsatser om Exposed habitat - Sida 2 av 53
Selection of habitat and resources during migration by a large mammal : a case study of moose in northern Sweden
Migration is a worldwide phenomenon that has occurred for thousands of years in a vast variety of species. The general knowledge of migrating animals is poor even though billions of animals from a range of different groups migrate every year. The human impact on migrating ungulates is high and many populations are declining globally due to direct and indirect causes. Hence it becomes vital to study the migration phase and the habitat and resources selected during migration. The objective with this study was to identify the habitat characteristics and resource selection of moose during migration and compare the selection between different seasons and utilization distribution (relative frequency distribution for the points of location of an animal over a period of time) categories.
Habitatmanipulering, en tveeggad bekämpningsmetod? : potentiella möjligheter och risker med alternativa födoresurser och skyddande habitat
Bevarande biologisk bekämpning är en bekämpningsstrategi som används för att bevara eller öka mängden av en specifik naturlig fiende till den skadeorganism som ska bekämpas. En skillnad i jämförelse med andra strategier inom biologisk bekämpning är att inga biologiska bekämpningsorganismer tillförs, i stället främjas de naturliga fiender som redan finns i odlingen och det omgivande landskapet. Habitatmanipulering är en metod inom bevarande biologisk bekämpning som bygger på en förändring av de naturliga fiendernas habitat som skall resultera i en förbättrad tillgång av nödvändiga resurser så som alternativ föda, skyddande habitat och alternativa bytes- och värddjur. Den här litteraturstudien undersöker potentiella möjligheter och risker med två metoder inom habitatmanipulering. Den ena metoden bygger på att inkludera blommande växter i en odling för att skapa en förbättrad tillgång av alternativa födoresurser, så som pollen och nektar, till naturliga fiender.
Habitat preference and dispersal of a sandassociated beetle, Apalus bimaculatus
Species that have a high degree of specialization and poor dispersal ability can be more prone to extinction than more generalist species and good dispersers. How these species traits affect the viability of populations is dependent on landscape factors,such as isolation and connectivity. Additionally, interactions between species (e.g. symbiosis), and how these interactions vary spatially and temporally can have a large impact on populations. When the range and habitat areas of a species continuously decrease, management strategies are often needed if the species shall be able to survive.
En studie av hållbara alternativ till odlingstorv : - vid jordförbättring inom trädgård
Pharmaceuticals are environmental pollutants that are a major threat to aquatic ecosystems and very little is known about their ecological consequences. In this study growth, survival and behaviour (sociability, activity and boldness) of perch fry (Perca fluviatilis) were examined in order to study the possible effects of exposure to a benzodiazepine anxiolytic drug, Oxazepam, during embryonic development. The study tested following hypotheses: (1) perch growth is affected positively by exposure during embryonic development; (2) early perch survival is affected positively by exposure during embryonic development; and (3) boldness and activity increases while sociability decreases in perch fry exposed during embryonic development. Embryos of naturally spawned perch were exposed to water with two different concentrations of Oxazepam. The embryos were exposed during different parts (24-hour periods) of the embryonic development, because embryos may be more vulnerable at certain times during embryonic development and/or because the exposure at different times can produce different effects.
Balis trädgårdar
The urbanization of the world is increasing. How it affects bird populations have been well studied during the last decade, and comparisons between urban and non-urban habitats have been carried out. A common method for measuring habitat quality is to calculate the population density. This method is easy to use, but have been criticized during the last couple of years. In this study, data of population densities was compared with data on reproduction success.
GIS-modellering av habitat för vitryggig hackspett (Dendrocopos leucotos) som hjälpmedel i naturvårdsplanering på landskapsnivå :
The white-backed woodpecker is a forest bird being critically endangered in Sweden. The species is dependent on older forests rich in deciduous trees and dead wood. The main problem for the survival of this species is present shortage of habitat. Conservation work on this umbrella species is at present focused on finding remaining or emerging habitat networks. Large areas are scrutinized in search for suitable habitats to be protected or managed for the species sake.
Vems landskap ska förändras för att öka den biologiska mångfalden? : En studie av skillnaderna i odlingslandskapets konnektivitet med avseende på två skyddsvärda arter med olika preferenser
Organisms relevant for nature conservation dont follow administrative borders. Because of this there is a need for a landscape perspective within conservation and planning, and a need for the species of interest to have legal protection. Network analysis adapted for ecological purposes has grown to become a powerful tool for studying and communicating the relationships between species dispersion and access to habitat. In this study the following question is posed: How is the Osmoderma eremita and the Pernis apivorus dispersal possibilities in the small scale cultivated landscape of Borås affected by exploitation in respect to a) dispersal ability, b) habitat quality, c) position of habitat patches in a network? The analysis were based on municipal and regional nature conservation data, which in due to confidentiality is not accounted for in the report by maps, coordinates, etc.
Större svartbagge Upis ceramboides i norra Hälsingland : förekomst, substratkrav och effekter av skogsbrukets naturvårdsåtgärder
Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.
Läkemedlet Oxazepam påverkar abborryngel : Exponering under embryonalutvecklingen ger effekter på tillväxt, överlevnad och beteende
Pharmaceuticals are environmental pollutants that are a major threat to aquatic ecosystems and very little is known about their ecological consequences. In this study growth, survival and behaviour (sociability, activity and boldness) of perch fry (Perca fluviatilis) were examined in order to study the possible effects of exposure to a benzodiazepine anxiolytic drug, Oxazepam, during embryonic development. The study tested following hypotheses: (1) perch growth is affected positively by exposure during embryonic development; (2) early perch survival is affected positively by exposure during embryonic development; and (3) boldness and activity increases while sociability decreases in perch fry exposed during embryonic development. Embryos of naturally spawned perch were exposed to water with two different concentrations of Oxazepam. The embryos were exposed during different parts (24-hour periods) of the embryonic development, because embryos may be more vulnerable at certain times during embryonic development and/or because the exposure at different times can produce different effects.
Hotade arter i tallmiljöer på Sveaskogs mark i Västerbotten och Norrbotten : skötselförslag och analys av potentiell habitatutbredning
Skogens biologiska mångfald hotas främst genom den påverkan som människan har på naturen. Skogsbruk och bekämpning av skogsbränder leder bland annat till att landskap och habitat fragmenteras samt att mängden död ved minskar i skogen. Naturvårdsverket och länsstyrelser arbetar inom ramen för de nationella miljömålen med åtgärdsprogram för hotade arter. Detta som ett led i arbetet med bevarandet av den biologiska mångfalden. Många hotade arter har en dålig spridningsförmåga, därför krävs planering utifrån ett landskapsperspektiv där stora sammanhängande områden sätts av och restaureras.
Habitat preference and foraging behaviour in adult red-tailed monkeys (Cercopithecus ascanius)
The red-tailed monkey (Cercopithecus ascanius) is a small, alert and active animal inhabiting forests with dense vegetation and as such hard to observe in its natural habitat. The principal aim of this study was to scrutinize whether the methods, previously used in a behavioural study of the blue monkey (Cercopithecus mitis) can be applied in studies of the red-tailed monkey?s behaviour as well. Additionally, habitat preference and foraging behaviour of the red-tailed monkey were examined. The study was carried out between the 16th and the 22nd of March 2009 in the Sabaringo forest, located on the western border of the Masai Mara National Reserve.
The influence of forestry stands treatments on brown bears (Ursus arctos) habitat selection in Sweden ? an option for Alberta forestry?
The brown bear population in Alberta, Canada has been decreasing, while the Swedish has been increasing and all the affecting parameters are not known. This study examined the difference in these populations to see if an explanation could be found in differences between the forest management. The aim of the paper was to see if stand treatments had an influence of brown bears habitat selection in autumn in Sweden and how the results can be used in Alberta. This was done by analyzing bear positions in Sweden with forest data, and comparing forest management data for the study area in Sweden with forest management data for Alberta. The results displayed that mature forests over 60 years that have been commercially thinned are selected by bears rather than forests over 60 years that have not been commercially thinned in.
Nya träd för stadsmiljö
Trees in urban environment are exposed to extreme conditions, foremost the ones that grow in the hard packed soil along our streets. They are also exposed to damaging insects and fungal diseases both local and new ones spreading from South Europe. The global warming with warmer temperatures provides a longer growing season, making it easier for insects and fungus to establish a habitat. Based on these facts new tree species need to be available for future urban plantings.To determine what these trees would be an interview study began. Six people were selected who have experience in the field of urban environment planting.
Om pojkars situation i hederskulturer
Girls in honour cultures have been the subject of many studies and are often debated in the media. The purpose with this study was to focus on boys in honour cultures. I wanted to understand the situation of boys in honour cultures with a perspective of the rights of children. My central questions were: How is it to be a boy in honour cultures? Are boys in honour cultures exposed? How are they exposed? My study was a qualitative study in which I interviewed four professionals who meet boys in honour cultures in their work.
Habitatval, migrations- och furageringsaktivitet samt homing hos gädda (Esox lucius) härstammande från Österby myr, Gotland.
In this study the spawning migration activity, habitat choice (depth and temperature), foraging activity, duration of stay in the spawning site and homing-behavior was studied for anadromous pike (Esox lucius) in the wetland Österby myr, Gotland.The spawning migration was concentrated to dusk and dawn, a homing behavior was confirmed and there was no significant difference between sexes with respect to duration of stay. A difference in habitat choice and small variation in foraging activity between individuals was established..