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791 Uppsatser om Exposed habitat - Sida 3 av 53
Enumerating Atlantic salmon smolt production in River Vindelälven based on habitat availability and parr densities : consequences of using different density estimation methods
Habitat mapping was conducted in the main stem of River Vindelälven in the autumn of 2009 along the salmon distribution area. The aim was to estimate the quantity of potential reproduction areas, including spawning and juvenile rearing habitats. The mapping included 61 km of various stream sections along the river length of 269 km. The total area of stream habitats was estimated to 647 ha of which 396 ha (61%) were considered as either potential or optimal juvenile nursery habitats. The area of these two habitat classes were used to estimate the smolt production in the river by using electro fishing densities of juveniles (0+ per 100 m2).
Flipp eller flopp?: En kvantitativ studie om bloggens potential som marknadsföringsmedium
The blog has become a widely discussed subject, but while marketers do invest in blogs, there is little evidence on the how the blog works as a marketing tool. Therefore, we thought it would be interesting to create a greater understanding of the blog's potential communication effects. To demonstrate the potential of the blog in comparison with more traditional media, we decided to compare the communication effects achieved by a blog with those achieved by an online magazine. We pursued an experiment where we exposed an identical text about a brand to respondents in seven blogs and in seven online papers and measured the resulting communication effects in terms of attitudes and intentions towards the exposed brand. The quantitative study showed that the blog in some basic aspects works as a more traditional media; when the consumer forms positive attitudes toward a text in a blog, the attitude spills over to the attitude toward the brand, with higher buying and w-o-m intentions as a consequence.
The influence of active bomas on habitat choice of the common warthog (Phacochoerus africanus)
The common warthog (Phachocoerus africanus) is a relatively long-legged pig with noticeable curved tusks, a short neck and three pairs of facial warts. It has four recognized subspecies. The common warthog is a non-migratory ungulate living on the African savannah. It is a hindgut fermenter and predominantly dependent on high-quality foods. It prefers open areas for grazing but use bushes for cover.
Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?
The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.
Näsnarens framtid i ett näringsstatusperspektiv
Eutrophication has been a problem in aquatic systems for a long time. It is well known that the key nutrient to control the eutrophication process is phosphorus. Lately, it has been possible to reverse the process and recover lakes from eutrophication.During a long time Lake Näsnaren in Katrineholms kommun, Södermanland, has been exposed of a large amount of phosphorus from the city's wastewater. The lake has a great value as a habitat of rare species but also a high recreation value for people living in Katrineholm and Södermanland. Lake Näsnaren is situated in a Natura 2000 area.
Garnlavshabitat i Vilhelmina kommun
Intensivt skogsbruk har medfört stora förändringar i den boreala skogens struktur och sammansättning. Epifytiska gammelskogslavar så som garnlav, Alectoria sarmentosa, tillhör de arter som drabbats hårt av korta omloppstider och ökad fragmentering av skogen då de kräver gamla träd som substrat samt är känsliga för förändringar i mikroklimat. Vi har med en GIS-analys gjort en modellering över hur stor andel lämpligt habitat för garnlav som finns i Vilhelmina kommun samt hur det är fördelat i landskapet. Modellen baserades på en regressionsfunktion med data från Riksskogstaxeringens inventeringar av hänglavar som grund. En utsökning med kNN-data (satellitdata över Sveriges skogsmark) som bas gjordes och en karta över var i landskapet det förelåg hög sannolikhet att påträffa bra habitat för garnlavar producerades.
Spawning site selection of brown trout in habitat restored streams
During the timber floating era, most of Sweden?s watercourses were altered. This decreased the amount of available spawning habitats for salmonids, and hence had a negative effect on the riverine brown trout (Salmo trutta) populations. Reconstruction of spawning grounds is today a common measure in restoration of altered streams in Sweden. However, very little evaluation of the effectiveness of these reconstructed spawning grounds exists.
Suitability analysis of a reintroduction of the great bustard (Otis tarda) to Sweden
The great bustard (Otis tarda) became extinct in Sweden during the mid-19th century. Globally, populations have suffered dramatic declines during the past two centuries. Recently, local populations have stabilized or increased after hunting bans and conservation efforts. Despite positive trends the species is still classified by IUCN as vulnerable (VU), mainly due to withdrawals in the distribution. The limited distribution emphasizes the need for finding ?new? areas suitable for a translocation or reintroduction.
Artrikedom av kärlväxter i övergivna och restaurerade hagmarker : betydelsen av igenväxningsgrad och tid sedan igenväxning började
Continuously grazed grasslands have remarkably high plant species diversity. In Sweden this type of habitat has declined for the last two centuries. Changed land use has caused habitat fragmentation and loss of habitat quality. This has caused a great number of plant species to end up on the verge of extinction. To try to save this unique habitat and the species that are tied to it, lots of resources are laid on restoration of abandoned grasslands.
In this study, plant species richness of continuously grazed, abandoned and restored grasslands were related to degree of overgrowth, time since overgrowth started and rate of overgrowth.
Hot och våld i arbetslivet : - En kvalitativ studie om socialsekreterares utsatthet
The purpose of this study was to investigate how social services workers describe, the risk of being exposed to threats and violence in their profession. Six social services workers were interviewed, four from the Welfare Office in a major city and two from the Child and Family Services in a minor city. Results showed that the majority of social services workers consider themselves exposed in their profession, meaning that they feel there's a risk of a violent or threatening situation occurring in their work situation. All interviewees had experiences from some sort of threat or violence in a work related context and they attested that non-personal assaults, such as threats made through telephone, email and answering machines are more common than verbal assaults made in personal meetings. Being prepared and listening to ones intuition is a way of dealing with exposure when meeting with a client.
Utvärdering av näringsstatus inför återskapande av kalkkärr vid Hagebyhöga, Östergötland
Calcareous fens constitute a specific habitat which is uncommon in Europe and protected by the EU habitat directive due to its importance to several threatened species. Hagebyhöga in Östergötland is a calcareous fen habitat included in the Natura 2000 Networking Programme. Adjacent to the existing fen, a degraded fen area is situated. The area has been used for agriculture for several years but is now going to be restored to its former state by the county administrative board of Östergötland.When working with restoration of degraded fen areas it is important to aquire knowledge about the chemical soil conditions. Plant growth limited by phosphorus and low fertility are characteristic conditions for calcareous fens, whilst arable land usually is highly fertile and limited by nitrogen.The purpose of this study is to bring forth useful knowledge for restoring the degraded calcareous fen of Hagebyhöga.
Brown bear (Ursus arctos) den site concealment in relation to human activity in Scandinavia
As a hibernating species, the brown bear spend most of the winter months in a den as astrategy to avoid unfavorable conditions. The denning period is a vulnerable time for bears,making them unable to flee disturbances without losing valuable amounts of energy. Brownbears' wariness of humans and avoidance of anthropogenic disturbance often steer denningbears away from human infrastructure, and bears thereby avoid possible disturbance and itsassociated energetic costs. This study was carried out to test the hypothesis that bearsdenning closer to infrastructure select more covered den sites to compensate for the closedistance. Dens from 32 individuals were visited and analyzed in terms of sighting distance(a measurement for den horizontal cover) and habitat ruggedness, in relation to distances toinfrastructure.
Tungmetaller i metabolismen hos värphöns och slaktkycklingar
Mussel meal is a potential source of protein, with a good composition of amino acids, for laying hens and broiler chickens, and may replace the use of fish meal in organic poultry production. Lead and cadmium are heavy metals which occur in the environment and can be accumulated in mussels. When poultry are exposed to heavy metals, the metals are absorbed in the small intestine and distributed in the body in the form of ions, complexes or bound to proteins. In poultry, lead accumulates in bone tissue, liver and kidneys, while cadmium accumulates in liver and kidneys. Generally very low concentrations of these heavy metals occur in muscles of broilers which have been exposed to feed contaminated with cadmium or lead.
Undervegetation : användning av vedartade marktäckare i anläggning
The use of the robust and durable woody ground covers is increasing, not in the least in public places. The group includes low shrubs of different height that effectively build low, tight vegetation that covers the ground. Despite all the good qualities the knowledge about them is quite low and there are ideas about them of being dull.
The woody ground covers manage to struggle against weeds effectively by competing for nourishment and water, but above all, by the canopy of the ground covers that prevent the weeds from getting enough light. In that way the woody groundcovers can effectively compete with the annual weeds.
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.