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751 Uppsatser om Threatened species - Sida 50 av 51
Utvärdering av DGT-tekniken (Diffusive Gradients in Thin film) samt jämförelse mellan DGT-tekniken och ultrafiltrering
Rapporten baseras på genomförd litteraturstudie samt provtagningar som genomfördes i Kamlungeforsen, nära utloppet på Kalixälven i norra Sverige under första halvåret 2002. Proven togs dels med hjälp av DGT-tekniken och dels med ultrafiltrering för att bestämma koncentrationen av lösta element. Metallspeciering innebär att man tar reda på i vilken fas spårmetallerna befinner sig i ? lösta joner och komplex, kolloider eller partiklar. Många spårmetaller är viktiga för liv, men kan också fungera som gifter beroende på koncentrationen.
Neonicotinoids and honeybee health : the effect of the neonicotinoid clothianidin, applied as a seed dressing in Brassica napus, on pathogen and parasite prevalence and quantities in free-foraging adult honeybees (Apis mellifera)
Sub-lethal doses of neonicotinoids have been shown to negatively impact the health of honeybees. However, most studies to date have exposed bees only artificially to these pesticides under laboratory conditions. There have been just a few well designed and replicated studies of the
impacts of realistic neonicotinoid exposure on honeybees foraging under field conditions. In order to close this knowledge gap, and to test the influence of the neonicotinoid clothianidin on honeybees, we used a study system of 16 paired, spatially separated (>4 km) spring oilseed rape fields in the south of Sweden. The fields were paired according to land use, the surrounding landscape and
geographical proximity, using GIS.
Dagvatten i Märsta : förslag till anläggning för ekologisk hantering samt metodöversikt
Stormwater in urban areas has been treated as a problem for a long
time. The large proportion of impermeable surfaces inhibits the water
from infiltrating in the ground to the same extent that it does in nature.
This causes intensive surface flow during rain, which in turn causes
inconveniences such as decreased accessability, floods and increased risk
of desease spreading. Drainage through pipes is the traditional and usually
functional metod for storm water disposal. That is as long as water flows
are moderate. But precipitation varies naturally in amount and intensity
and additional impermeable surfaces make some pipes insufficient for
heavy or lasting precipitation.
Rekreation och utomhuspedagogik i tätortsnära skog : planering av skolskog och rekreationsanalys för Sätra, en stadsdel i Gävle
This Masters Thesis includes a survey of recreational habits and the attitudes towards forests of the people of Sätra, a suburb of the city of Gävle. The study also includes the planning and design of a forest suited for education in the same part of the city. The thesis is a part of a project called Tätortsnära skog, commissioned by the Swedish forest agency. The project aims to survey the recreational habits of the general public in the regions of Dalarna and Gävleborg. Tätortsnära skog is focused on cities with a population of more than 20 000 inhabitants, of which Gävle, Sandviken, Falun and Borlänge all fall within the category.
Till synes orörd skog : naturvärden och kulturhistoria i Rekdalen under 400 år
Nature conservation has for a long time been founded on the assumption that high ecological values depend on low human impact. In Sweden this has led to forests with these characteristics being strictly protected from human influences. However, it is also known that historical land-use can enhance ecological values in forests. Mountainous forests in Sweden, which have not been affected by modern forestry, have for a long time been considered as untouched by people. However, forest history research has in recent years shown that even these areas have been used by people for a long period of time.
Ligghall för utegångsdjur ? en sammanställning och analys av domar i djurskyddsärenden som handlar om ligghall till utegångsdjur åren 2007-2013
There is currently an ongoing discussion in Sweden about the need for weather shelter for farm animals being kept outdoors during the winter season. Currently, the national animal welfare legislation requires weather shelter providing the animals? with access to a dry and clean place to rest, but under certain conditions exemptions can be granted. The Swedish Board of Agriculture has put forward a hypothesis that there is a difference between judicial decisions in animal welfare cases dealing with weather shelters, as to whether the animal has shown to be suffering or not. The aim of the study was to highlight any weaknesses or difficulties when assessing animal welfare issues associated to the absence of or design of weather shelters.
Isbjörnars (Ursus maritimus) interaktioner och hägnutnyttjande på Orsa björnpark
SAMMANFATTNINGIsbjörnen är mycket populär hos djurparksbesökare och en viktig symbol för klimathotet, trots detta finns fortfarande många frågetecken kring hur vi ger isbjörnar i djurparker hög välfärd. I litteraturen har vi länge talat om isbjörnar som solitära djur men trots detta låter vi dem ofta dela hägn med andra isbjörnar på djurparker. Det har observerats positiva effekter av grupphållning av isbjörnar, bland annat sänkt förekomst av stereotypa beteenden, men vi måste vidare utreda vilken påverkan det har på deras välfärd. Ytterligare problem för isbjörnar på djurparker är stereotypt vankande som har observerats hos flertalet karnivorer som i det vilda rör sig över stora områden eller hemytor. Syftet med denna studie var att titta på hur isbjörnarna på Orsa björnpark utnyttjar sitt hägn, vilka beteenden som kan observeras samt hur stor del av observationerna de spenderar tillsammans.
Habitat selection of the European bison
Skogens konung eller präriens prins: var hör visenten hemma egentligen?
Visenten är Europas tyngsta nu levande landdjur. Då en vuxen tjur kan nå nästan två meter i mankhöjd och väga upp mot ett ton så är det sannerligen en uppseendeväckande best. Trots detta är den relativt okänd: många jag talat med har varit omedvetna om existensen av denna art. Av dom som känt till den har flera haft föreställningen om att den är utdöd, eller blandat ihop den med antingen uroxen eller myskoxen.
Valpens utveckling : ur ett fysiologiskt och etologiskt perspektiv
The first two weeks in a pup's life is called the neonatal period. This period is dominated by growth and development of organs and senses. The puppy is born blind and deaf and the physiological disability makes it unable to move properly. The neonatal period is characterized by a lot of sleeping. The pup receives the important milk and warmth from the bitch.
Utomhuspedagogiska rum : hur naturen kan användas som undervisningsmiljö
Outdoor education is a teaching method which has several advantages to traditional classroom tuition. Its ideas have a long tradition and find support in the current Swedish curriculum. The place for the tuition is a central aspect within outdoor education. This essay aims to investigate what good places for outdoor education look like as well as discussing how the characteristics of such places can be used when designing schoolyards. Previous research shows that nature has characteristics that suit outdoor education well.
Naturlika planteringar - hur lika och hur är de lika naturen? :
Sammanfattning (English below)
Jag har alltid tyckt om naturen och haft en föreställning om att all växtlighet som inte är tydligt anlagd, som en gräsmatta eller en rabatt, är något som naturen åstadkommit av sig själv. Mina ögon öppnades för alternativen när jag för första gången hörde begreppet ?naturlik plantering?.
Det här arbetets syfte är att ta reda på hur lik naturen naturlika planteringar egentligen är, om de är planerat naturlika eller något som används som utfyllnad. Syftet är också att ge en indikation på vilken status den naturlika planteringen har.
Arbetet består av tre delar. En historisk del som utforskar ursprunget till begreppet ?naturlik?.
Handen bakom Vegeholms engelska park - en studie av parken och dess uppkomst
A boom in horticulture characterized the 18th century in Sweden and Skåne. Parks and gardens were gradually built out to become, at the end of the 18th century, large and comfortable facilities which responded to European parks. During the late 1700s the new fashion came to Sweden. In Sweden it was named ?the English style? which directly refers to the English expression ?Romantic style?.
En upplevelsepark som stimulerar känselsinnet hos synskadade barn ? utformning och materialval
Abstract/////
Parks and green spaces are important to a lot of people today. Are these parks made for us all? Is it possible for a person with a sight disability to explore and take part in all the things these places have to offer? They can probably take in some, but I think there are more effective ways of planning for the blind and sight disabled allowing them to explore using their tactile senses.
The environment is vital for children?s development.
Att restaurera forna tiders beståndsstruktur : ett exempel från Jämtgaveln
In Sweden today so-called "prescribed nature conservation burning" is performed due to the change in silvicultural law, certification and an increased knowledge regarding the field of fire in the forest landscape. The aim is to re-create structures and qualities made by the fire regimes of the past, though on a much smaller geographical scale. The structures and qualities to be re-created are for example broad leaf stands, trees with large diameter, heterogeneous stands regarding variables such as age and diameter. If we increase our knowledge of the constitution of forests characterized by fire, then we will be able to set goals for what achievements to reach both on landscape scale and stand scale.
The aim of this paper is to try to describe how a stand from the past was composed regarding mainly the spatial arrangement and compare it with the stand of today in the same place. This to be done by using relict material, that is stumps and dead standing trees.
Kan risken för spontan contortaföryngring elimineras genom hyggesbränning? :
Sweden has almost 600 000 hectares planted with lodgepole pine, and large areas are soon ready to be clear-felled. The provenances that have been planted are producing high level of permanently closed, so called serotinous, cones. In their natural setting, the Canadian boreal forest, these cones are opened mainly after crown fires when the heat make the resin between the cone scales melt, which releases the seeds. This is viewed as an adaption to the fire regimes that prevail over the natural distribution area of lodgepole pine. Because of the short flame-exposure that occurs in a crown fire, the seeds can survive.