Sök:

Sökresultat:

782 Uppsatser om Refugee species - Sida 21 av 53

En skogshistorisk jämförelse mellan två närbelägna landskap med olika mångfald i östra Småland :

This study shows the historical development of the forests in Hornsö and Ebbegärde state forest area in eastern Småland situated in southern Sweden..

Död ved i gallrad skog och nyckelbiotoper : en jämförelse av habitatkvaliteter för vedlevande lavar och mossor

A high amount of dead wood is one of the most important prerequisites for high biodiversity on forest land in Sweden. Dead wood is most abundant in young forests, thinned forests, woodland key habitats and protected forest land. In old-growth forests most of the dead wood consists of logs and snags, whilst in managed forests a huge proportion of dead wood is made up of logging residues like stumps and FWD, fine woody debris (< 10 cm diameter). All these different types of dead wood may serve as substrates for epixylic bryophytes and lichens. However, few studies have been conducted on the relative importance of these different fractions of dead wood for the occurrence of bryophytes and lichens, especially when considering dead wood on thinned forest land.

Samverkan på svenska mötesdestinationer.

Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization. The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.

Jämförande studie av normal ERG-svar hos tre olika hundraser :

The purpose of this study was to compare normal electroretinographies (ERGs) from three different canine breeds in order to evaluate if there were any marked similarities or differences between these breeds as to ERG responses. It is known that healthy dogs from different breeds but also dogs within the same breed but in different age categories may have different appearances of their ERG responses. This may be a problem when evaluating if an ERG is normal or not from a dog within a breed not previously examined. Because of this it is important to obtain normal values for each breed and age group in order to be able to use these for later comparisons of ERGs obtained from individuals affected with various retinal diseases. In this study we have chosen to examine dogs within the three breeds: Labrador Retriever (LR), English Springer Spaniel (ESS) and Chinese Crested Dog (CCD). All of these breeds may be affected with hereditary retinal diseases such as Progressive Retinal Atrophy (PRA). It is possible that ERG-responses vary due to a number of different factors.

Södras gröna skogsbruksplaner ur ett landskapsperspektiv :

The aim of the "Green forest management plans" is to help forest owners to reach the environmental goal of the forestry act. But are they able to do that? Is it possible to plan preservation of species on single estates? How do single-estate-plans differ from a landscape analysis and how can the landscape approach be used in operative planning? This work was initiated to give an answer to these questions. This study was made in a landscape of 4200 ha in Östergötland county, south-eastern Sweden. A lanscape analysis was made and then compared to the Green forest management plans in the same area. The nature conservation areas (areas that were set aside to be managed with environmenatl goals) differed quite a lot between the two alternatives.

Skottbetning på granplantor i Kolmården : omfattning och påverkande faktorer

In the Kolmården area, northeast of Norrköping in south-central Sweden, it was discovered that shoots of spruce Picea abies, plants to a seemingly large extent had been browsed by deer. The area inhabits a dense red deer population, alongside with moose and roe deer, and red deer is thus suspected to cause the damage. The main purposes of this study are, however, to estimate the extent of the shoot-damage and to investigate what factors that may affect the browsing of shoots. For each stand information was recorded about the age of the plants, area for the stand, height over the sea for the stand, site productivity, type of plants and stand-history. The study was done in three areas: Simonstorp, Stavsjö and Valinge. At Simonstorp and Stavsjö, respectively, 10 stands were chosen for study and on Valinge six stands. In each stand, 10 plots were sampled.

Djurparkernas tillgänglighet av information och dess innehåll: är den tillräcklig?

The purpose of zoos has changed over the decades. From being menageries where wealthy people showed their collections of exotic animals to today?s zoos where science, conservation and education has become a central part of their work. Education in zoos gives them the opportunity to spread the knowledge about ecology, biology and biodiversity to the general public. Their aim is to change the public?s attitudes towards our wildlife and raise awareness about the threats that exists against our planets biodiversity.

Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides

Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides. This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very rare and decreasing, and Norrbotten where this study was conducted.

Några vanliga ogräs : en litteraturstudie av arternas biologi samt förebyggande och direkta kontrollåtgärder

The Swedish Board of Agriculture initiated this undergraduate thesis. There is a database on their homepage that includes chemical treatments for different weed species. There is also space for preventive and mechanical control methods. This is an undergraduate thesis that reviews these control methods for the most important weeds in Sweden. The species reviewed are: Creeping perennials: Common Couch Elytrigia repens (L.) Desv. ex Nevski Creeping Thistle Cirsium arvense (L.) Scop. Perennial Sow-thistle Sonchus arvensis L. Field Horsetail Equisetum arvense L. Colt's-foot Tussilago farfara L. Stationary perennials: Dock Rumex L. Mugwort Artemisia vulgaris L. Dandelion Taraxacum F.

Smittskyddsrutiner vid flytt av djur mellan djurparker

Animals in zoos live in small enclosed areas. If a pathogen is introduced to the zoo, the animals are extremely vulnerable. The highest risk of introducing new pathogens occurs when new animals are introduced to the collection. Therefore it is essential that zoos have a protocol in place for disease prevention. This review has studied literature on the subject of disease prevention protocols when translocating animals between zoos.

Individuell tillväxt och substratval hos en lokalt differentierad population av Asellus aquaticus

Local differentiation may occur during a short period of time and is part of the formation of new species. The isopod Asellus aquaticus is an example of a species in which local adaptation has occurred during a short period of time. An establishment of stonewort (Chara spp.) vegetation in Lake Tåkern (in the 2000) resulted in two different Asellus ecotypes; a lighter pigmented, smaller one that lives among stoneworts grazing periphytic algae, and a darker, larger ecotype that feeds on decaying leaves in reed (Phragmites australis vegetation. The purpose of this study was to examine whether there are differences in growth between ecotypes, depending on whether the food was periphytic algae or leaves, and to study the choice of substrates between the two food types. For the study, animals from both habitats were brought in from Lake Tåkern to the laboratory.

Spegel, spegel på väggen där, säg vilken norm jag ska följa här? : -En kvalitativ studie om jämställdhetsarbete och genus på HVB-hem för ensamkommande flyktingbarn

Syftet med denna studie var att utifrån ett genusperspektiv undersöka hur två HVB-hem för ensamkommande flyktingbarn arbetar med jämställdhetsfrågor. Detta undersöktes genom fyra halvstrukturerade intervjuer med personal på HVB-hem för ensamkommande flickor och pojkar mellan 14-17 år. En kvinna och en man på respektive boende intervjuades. Intervjuerna spelades in och det transkriberade materialet analyserades utifrån socialkonstruktivistisk teori samt utifrån ett genusperspektiv. Resultatet av undersökningen visar hur stereotypa föreställningar kring kön konstruerades i det sociala arbetet med ensamkommande barn.

"Språket är nyckeln till integration" : En studie av integrationsarbete med ensamkommande pojkar

The purpose of this study was to explore the approach of the personal in residential care homes, legal guardians and Refugee secretaries consider as effective in their efforts to care for and guide unaccompanied boys in the Swedish society. With the help of qualitative method and semi-structured interviews, we have taken note of eleven informants? perspective on what approach they believe to be essential in the work of integration process with unaccompanied boys. We used Empowerment and the Swedish Integration Board´s proposal on indicators of integration as a theoretical base. The results show among other things, that our informants believe the keys to integration in Sweden for the unaccompanied youth are the Swedish language, education and a stable social network.

Utilization of different habitatsin Colobus angolensis palliatus in the forests of Diani Beach, Kenya

The Angolan black and white colobus monkey (Colobus angolensis palliatus) is an arboreal primate that inhabits coastal forest fragments on the south cost of Kenya and is consequently vulnerable to forest fragmentations. The study was carried out in March and April 2011 in Diani Beach in Kenya where two of the largest populations of the species are distributed. This study is a pilot study to test methods for a Master?s thesis. The aim was to investigate any variations in use of two habitats of C.a.

Tetratermmodellering och regressionsanalyser mellan topografi, tetraterm och tillväxt hos sitkagran och lärk : en studie i norra Island

This study was made in an attempt to give the forest research centre Mógilsá a producedtetratherm map and a better understanding of how topography and temperature influencethe growth of two tree species. The digital tetratherm map model, covering the northernpart of Iceland, was developed to investigate the correlation between tetratherm and thegrowth of Picea sitchensis and Larix (sukaczewii + sibirica). The study confirms theusefulness of digital terrain models in providing data for a lot of different factors and forthe tetratherm model. Hopefully will this tetratherm map be used in future studies.Secondly, investigations were made correlating the growth of the two species againsttopographic factors representing height above sea level, distance to the sea, slope andtopex. Thirdly, investigations were made comparing the aspect and the ground shape tothe growth.The growth rate of Larix had strong significant correlations to the tetratherm and thedistance to the sea- factors.

<- Föregående sida 21 Nästa sida ->