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681 Uppsatser om Species - Sida 36 av 46
Den globala uppvärmningen : vad kommer att hända med morgondagens värld?
Mankind faces a serious threat. Its activities, for example the burning of fossil fuels, have led to an enhancement of the greenhouse effect - something that has given rise to a global warming. The climate is becoming warmer, a change that has important effects on the nature as well as for humans and their society. Sea level rising, extreme temperatures are becoming more common, glaciers and other ice caps melt and storms becomes more intense when they appear. The main cause is the emission of greenhouse gases into the atmosphere - carbon dioxide in particular.
Nitrogen fixation among boreal feather mosses along a clear-cut chronosequence
The Swedish boreal forests are limited by nitrogen (N) availability. While biological N2 fixation by cyanobacteria hosted by pleurocarpous feather mosses are important sources of N input to natural boreal forest ecosystems, little is known about the patterns of N2 fixation in silvicultural systems. This study investigates the biological N2 fixation rates of two boreal feather moss Species (Pleurozium schreberi and Hylocomium splendens) along a chronosequence from clear-cut to mature forest, as well as the vegetation characteristics along the chronosequence. Measurements and samples were collected from 32 forest sites that were classified into four age classes (clear-cut, pre-commercially thinned, thinned and mature forest). The sites were located near the city of Arvidsjaur in northern Sweden.
Francisella tularensis subspecies holarctica : the curious case of a water- and mosquito associated bacterium in Sweden
Francisella tularensis, the causative agent of the zoonotic disease tularaemia, is highly contagious and potentially fatal for a wide range of wildlife Species of the northern
hemisphere, also humans. Although recognized as a pathogen for over 100 years, much still remains to be elucidated concerning the ecology and transmission of the bacterium, hence this literature overview aims at compiling data regarding the aquatic association and the role of
mosquitoes in transmission of Francisella tularensis subSpecies holartica, the sole subSpecies in Sweden. While a linkage between the bacterium and natural waters stands beyond dispute, there is no consensus in the literature concerning its potential as a reservoir. However, two
prevailing theories can be distinguished; one proposes the water association being mammaldependent and thus merely the result of contamination from semi-aquatic mammals living in
close vicinity to the water source. The other, quite contrary, suggests mammal-independence and hence that water, possibly in association with protozoa, serves as an environmental reservoir for the bacterium.
Skillnader i kungsörnens (Aquila chrysaetos) flyttningsmönster beroende på ålder och klimatfaktorer : En studie för skyddet av kungsörn
This study examines the factors that influence the seasonal movements of Golden Eagles (Aquila chrysaetos), and can thus provide important information that helps to improve the protection of the Species. There were two main purposes of this study. First, I wanted to analyze the difference between preferences of juvenile and adult Golden Eagles in their choice of southern or northern hibernation areas. Do younger eagles prefer moving longer distance to southern areas of Sweden? Second, I wanted to investigate how the climate influenced the choice of date of migration in the fall.
Naturvårdsrestriktioners effekter på brukandet av ädellövskogen i Skåne :
Restrictions in nature conservations are increasing the influence of forest management. Nobel broadleaved forests are more influenced than other forests, because they are considered to be more valuable than other forest types in Skåne. There has been a lack of knowledge about the amount that is set-aside for nature conservation and what types of forest that is concerned.
These are the main questions to be answered in this thesis. Moreover has the timber quality been compared between set-aside and non-set-aside areas since it affect the financial conditions for the forestry in nobel broadleved forests. The last asked question deals with the financial consequences of set-aside.
Molecular analysis of insecticide resistance in pollen beetle (Meligethes aeneus)
The escalating usage of pyrethroids has resulted in an increased awareness about resistance towards pyrethroids in insects. Pyrethroids inhibit voltage-sensitive sodium channels (VSSC) in nerve cell membranes and are composed of synthetic molecules based on pyrethrins present in pyrethrum extracts from Chrysanthemum Species. VSSC are transmembrane proteins that are important for electric signalling over the membrane in insects. Mutations in the gene encoding the sodium channel have proved to be a common reason for resistance against pyrethroids. Pyrethroid resistance among pollen beetles is spread all over Sweden and also abroad and is increasing.
Contortatallens odlingsvärde i Götaland
The third most common conifer in Sweden is Pinus contorta (lodgepole pine). It originates from the western part of North America and was brought here in the end of the 1920s. The lodgepole pine is today allowed for commercial plantations in central and northern Sweden, excluding high altitude locations. Since 1979 only plantations with scientific purpose are allowed in south-central and south Sweden.
This document is focused on how lodgepole pine manage perform compared with Pinus sylvestris (Scots pine) in the southernmost part of Sweden, Götaland. The idea came from the fact that the Swedish government is evaluating a notification from the National Forest Agency that suggests lodgepole pine to be allowed for commercial plantation even in southern Sweden.
Skiljer sig hundvalpars lekbeteende åt mellan raser och kön? :
There are many theories why animals play but none have jet been proven. During observation on Canids, play seems to be important when they learn to control the intensity of the bite and to facilitate the social structure within a group. When dogs play they perform behaviours that otherwise are used during hunting, reproduction and aggression that in another context would be for example hostile. The dog is one of the Species that we humans have domesticated and they have been exposed to an intense and concentrated breeding so they can function in different areas, for example herding and hunting. This breeding has resulted in that the pure bred dogs can be very different between the breeds.
Naturvårdshänsyn i boreal bruksskog : En studie om avverkningar och avverkare i skogarna runt Saxdalen i södra Dalarna
As the past century?s technological development has progressed the Swedish boreal forests have transformed into dense, highly productive, homogenous and coniferous forests. The area around Saxdalen in Ludvika municipality has long been dominated forests which have been heavily worked since the 18th century. There are in Ludvika 119 000 hectares of productive forest land. Around 70 percent are owned by forest companies and 20 by private forest owners.
Development of green space in Dar es Salaam, Tanzania
In Dar es Salaam, as in many cities in developing countries, green areas are decreasing due to the fact that the growth of buildings, infrastructure and services has become a priority. As the population increases more buildings and infrastructure are needed and much of the building activity takes the form of uncontrolled settlements, which encroaches the public green space. Dar es Salaam has approximately three million inhabitants, of which about 70 percent are living in informal settlements.
The aim with this study is to make a design proposal for a park and recreation area where the Msimbazi river basin in the centre of Dar es Salaam is today.
The basin consist of a few playing fields, footpaths and some urban farming, but apart from this it mostly consists of unused grasslands, swamps and forests. Because it is an unsafe place and badly connected to the rest of the city infrastructure, it has become a barrier. The annual flood combined with the constant still shallow water creates a good breading ground for malaria mosquitoes.
?Processutveckling av metod f?r tillverkning av en funktionell tibetansk mejeriprodukt?
Probiotics is a special group of health products on the market. The most common type of these is live cultures of lactic acid fermenting bacteria from raw milk . These include, among others, yogurt and various trademarks such as Hälsofil ®, Acidophilus ®, Dofilus ® and Kefir ®. Such products are often used by patients who are treated with antibiotics to combat the intestinal flora eliminated, thus causing digestive problems. The present work deals with yet another type of health product, viz.
Bibliografering av tryckt skönlitteratur och musikalier : En komparativ studie
Literature and music as an expression of art have some parts in common, others can quite differ. Both are using a language, and both can exist in written representations. You can find such written or printed items in library catalogues. The aim of this two years master's thesis is to examine how cataloguing of printed fiction-literature and printed music looks like, what differences you can find in cataloguing of printed literature and printed music.This study is based on a comparative methodology and two different theories are used. The first describes the common tasks for library catalogues as they are known traditionally and recently (as FRBR-conceptual model), the other is a comparison of the two art-Species literature (fiction) and music.This paper's first part is a comparison of how printed literature and printed music are catalogued in the Swedish national catalogue LIBRIS.
Förslag på sju olika träd som kan ersätta befintliga träd på kyrkogårdar
Växtligheten på dagens kyrkogårdar har i regel knappt en 100?200-årig historia. Det var i slutet av 1800-talet som kyrkogården efterhand fick det utseende som vi förknippar med en gammal kyrkogård, med höga kyrkogårdsträd och en kyrkogårdsmur.Det trädsortiment som har använts i trädkransen som inramar kyrkogården eller trädrader längs gångar, har varit begränsat beroende på traditioner och trädens lämplighet. Man valde ofta arter utifrån de lokala förutsättningarna, såsom alm, lind, lönn och björk. Under en längre tid har sjukdomar på en del trädarter brett ut sig och hotar trädbestånden på våra kyrkogårdar.
Håller den måttet? En prövning av Katharina Reiss metod för översättningsanalys
Uppsatsen tar sig an problemet vilken metod som är lämpligast för analys av översättning av skönlitterära verk. Två metoder för översättningsanalys testas och i poppersk anda får den ena försöka vederlägga den andra. Den metod som får försvara sig är Katharina Reiss och den som får försöka vederlägga hennes teser är en metod som jag utvecklat med stöd i E.A. Nidas teorier. För att testa teorierna görs en verklig analys på en existerande översättning: Per Holmers svenska översättning av Hugo Claus nederländska roman De geruchten.Resultatet av utmaningen blir att Reiss metod och metoden med stöd hos Nidas befinns vara ungefär lika bra när det gäller att leverera ett användbart resultat.
Passage efficiency and migration behavior for adult Atlantic salmon at a Half-Ice Harbor fish ladder
Due to exploitation of the world?s rivers, the upstream migration of anadromous Species is frequently delayed or even prevented. To mitigate these problems and allow fish to migrate past obstacles, structures such as fish ladders have been developed. However, recent studies show that many of the present fish passage facilities are deficient. Monitoring and evaluation of passage facilities is therefore crucial to enable necessary adjustments.