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751 Uppsatser om Threatened species - Sida 42 av 51

Emerging zoonotic viruses : what characterizes them and what are the risk factors for their emergence?

Emerging infectious diseases poses a great future threat, not only to humans but also to domestic animals and wildlife. Even though the majority of these infections only cause minor health problems, the relatively recent emergence of HIV clearly illustrates that the next major human pandemic may surface at any time. Regardless of what the name indicates, most emerging human pathogens are not believed to be recently evolved, but to have existed previously in the natural environment. Most emerging pathogens are zoonotic, i.e. able to infect animals besides humans.

Migration losses of Atlantic salmon (Salmo salar L.) smolts at a hydropower station area in River Åbyälven, Northern Sweden : passage fates at a reservoir, a power house and a bypass structure

A large number of rivers in northern Sweden have hydropower developments that cause negative effects on both up- and downstream migrations of anadromous species like Atlantic salmon. So far, most attention has focused on the hindrances of adult fish during their upstream spawning migration. However, since turbines in power stations cause losses on downstream passing fish, the focus on negative effects on smolts has increased. The aim of this study was to compare three different causes of losses of salmon smolts passing downstream through a power station area in the flow-controlled River Åbyälven in northern Sweden.A total of 61 wild salmon smolts were caught and radio-tagged in the River Åbyälven during their downstream migration in June 2009. The salmon smolts were released at three locations, 1.1 km upstream from the power station, in the turbine intake and in the upper part of a fishway, acting both for up- and downstream fish passage.

En pilotstudie av unghästars användning av ligghall i grupphållningssystem

Today, individual indoor stalls and individual outdoor paddocks are the most common way to house horses in Sweden. The way that we manage, house and feed the horses are not optimal for the species natural basic behavioural needs. However, the awareness of this grows in the context of research and the emergence of alternative housing systems. One of the alternatives to the traditional format in individual boxes is called group housing. Group housing systems allow horses to live in herds and they can choose how they want to distribute the hours of the day between movement, resting and foraging. The purpose of this study is to examine how frequently the young horses in a group housing system use the indoor lying area.

Social kontakt för hund i rastgård ? när kan kraven anses uppfyllda?

People in Sweden have more and more dogs in their care, and several of these dogs are kept in kennels in back yards for various reasons. According to Swedish animal welfare legislations the need for social contact for dogs has to be met. However, there are few details presented on how to meet the need and when it can be considered satisfied. Does the dog need human contact to fulfill the need, or is the company of other dogs enough? This study aims to specify what can be acceptable when it comes to fulfilling dogs? social needs in accordance with the Swedish animal welfare legislation.

Inter-species embryo transfer in South American camelids

Embryotransfer är en metod där ett embryo i tidigt stadium flyttas från en donator till ett mottagardjur som sedan bär dräktigheten till förlossning. Det innebär att donatorhonan kan donera flera embryon under en säsong då den vanligtvis endast skulle kunna producera en avkomma. Embryo transfer är således en metod för att snabba på det genetiska urvalet i en grupp djur. Bland de mycket ekonomiskt värdefulla alpackorna i Peru, där många av herdarna saknar alternativa inkomstkällor kan embryo transfer bidra till ett mer effektivt avelsarbete och i förlängningen en bättre levnadsstandard för alpackaherdarna och deras familjer. Studien beskriver ett experiment där ett protokoll för embryo transfer från alpacka till lama utförs under fältmässiga omständigheter på en forskningsstation i de peruanska Anderna.

Provtagning av trädkärnor för att bedöma föroreningsgraden av klorerade lösningsmedel i grundvatten

Chlorinated aliphatic hydrocarbons (CAH´s) were used widely within dry cleaning facilities and for metal degreasing until their toxicity was discovered. PCE is still used as dry cleaning liquid. Today CAH´s are found in soil environment at places where they have been used in the past. The CAH-concentration in trees growing on contaminated land has quite recently received attention as a cheap and effective way of assessing the extent of a CAH-contamination. The method has however, not been put into use in Sweden.The aim of the study has been to investigate whether the CAH-concentration in tree cores could be used to delineate the spread of CAH in a soil environment under Swedish conditions in different seasons.

Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)

Peat  lands  are  a  great  potential  resource  for  increased  forest  growth  in  Sweden, there  are  approximately  6.5  million  hectares  of  peat  lands,  whereof  around  70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste  land.  There  are  over  200  000  hectares  of  peat  land  that  is  already  drained and  wooded,  and  that may  be  suitable  for  fertilization.  Forest  production  on  peat soils  usually  requires  drainage  and  fertilization.  Dewatering  requires  ditching  the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The  purpose  of  this  work  was  to examine  the effects  of  potassium  fertilization  on the  growth  of  spruces  that  were  planted  on  drained  peat  land  and  how  different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance  transport  in  the  tree.  Potassium  is  also  important  for  the  carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter  resistance  of  many  species.  Potassium  is  not  found  in  any  organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was  left  without  fertilization.  All  plots  that  were  fertilized  with  potassium  grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality  estimation  of  wetlands  after  ditching  (dikningsbonitering).  The  plot  with most  potassium  produced  after  fertilizationaproximately  in  level  with  theoretical estimations.  Key  words:  Peat  land,  Fertilization,  Ditching,  Growth,  site  quality..

Synchronizing migration with birth: an exploration of migratory tactics in female moose

Migration and giving birth are crucial decisions for animals during their life cycle, which may have lasting consequences on their population demography and fitness. Migration can entail a variety of possible effects for an individual, such as access to high quality food and reduced risk for predation. The moose (Alces alces) in northern Sweden is partially migratory and moose females are known to give birth to one or two calves. The synchrony between time of calving and timing of migration has not been compared before, especially in terms of energy maximizing and time minimizing perspectives, which may provide vital cues for fitness benefits of migration. I investigated effect of timing of birth and individual life history on distance, timing, stopovers and duration of 190 individually marked female moose that have been tracked for multiple years in ten different areas in northern Sweden.

Djurskyddskontroller ur lantbrukarnas perspektiv - från kommun till länsstyrelse

On the first January 2009 the official animal welfare control were transferred from the municipalities to the County Administrative board. With this transition, some changes occurred for those who work as animal welfare inspectors. The aim for this study was to examine farmers' view on the transition between the municipalities and County Administrative board, in order to compare the two authorities. I have also studied the farmers view about animal welfare inspectors' knowledge, both theoretical and practical. The questionnaire also included questions about farmers' view on animal welfare legislation.

Skyddsrum och kärnvapen : En diskursanalys av 1950- och 1960-talets försvars- och civilförsvarsdebatt i svensk press

Shelters and Nuclear weaponsA discourse analysis of the Swedish defense and civil defense debate during the Cold warSweden during the Cold War set into motion one of the world?slargest civil defense policies at the time, second only to neutral Switzerland. The governments expenditure was far greater per capita than both that of USA and Soviet Union and included massive evacuation plans for Stockholm and other large cities in Sweden, with the hopeful expectation to bring down the amount of people in each of them to 15000 in case of a foreign hostile nuclear attack. The policies included construction of shelters with room for 2,5 million of about 7 million citizens in total at the time along with gasmasks for the whole population. Not only this, Sweden was considered one of the biggest military powers of that time in relation to its size and population.

Inga miljövinster med ekologisk produktion? : Lägesrapport över den svenska jordbruksdebatten

Organic agriculture is financially promoted in Sweden by special environmental support and as consumers we are all encouraged to buy organic food. At the same time scholars at the Swedish University of Agricultural Sciences claim that organic farming does not provide any environmental benefits. The main criticism is that organic farming has lower yields than conventional, which means that more land is needed to produce the same amount of food as in conventional farming, leading to deforestation and loss of biodiversity. As for climate change, the critics claim that the significantly higher productivity in conventional crop production compared to organic, releases surplus land, which could be used for bio-fuel production and thereby replace the fossil fuels. The critics also claim that organic farming causes higher nutrient leaching than conventional.

Identifiering av fel i skogliga beståndsregister med hjälp av satellitdata :

This thesis has focused on the possibility to use a satellite image method developed by Metria Mijöanalys to identify stands that are wrongly registered in Holmen Skogs database. The method is only intended for identifying stand with poor descriptions in Holmen?s database that needs to be updated and not for updating the stand information. The study area is located several km west of Hudiksvall on the borderline between Gävleborgs- och Västernorrlands län. The area is covered by a SPOT image from 2005. By which Metria Miljöanalys has made estimates of forest parameters for all stands in the area, and compared them with corresponding estimates according to the stand database.

Översvämningskartering av Vombs ängar

Vomb meadows is an area well knows for its rich bird life. During the 19:thcentury until mid 20:th century, the meadows were flooded annually in order toincrease the hay yield. The river Klingavälsån situated along the west side of themeadows, used to be a shallow river, meandering across the landscape. In the1940?s the river was straightened and made deeper.

137Cesium i myrsamhällen i Gävleborgs län 24 årefter Tjernobylolyckan

24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.

Kaninhållning för sällskapsbruk

The domesticated rabbit stems from the European Wild rabbit and researchers have found that they share most of the characteristics and behaviors of their wild ancestor. They form mating groups in which strong hierarchic orders are formed and they are known for their ability to dig warrens which serve as one of the most important resources for this species. Although research has been performed to increase the welfare of rabbits kept in laboratory settings little is known about the housing, behavior and welfare of the pet rabbit. Among the research that has been performed within the area results have shown that the animals are kept in small solitary cages and that although many rabbits are purchased mainly for the children many animals cannot be handled by children due to display of aggression. Another conclusion drawn is that the animals are kept in ways that differs greatly from their natural environment.

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