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918 Uppsatser om Species interactions - Sida 13 av 62

Naturreservat : en bra naturvårdsåtgärd för att bevara enskilda arter och/eller bevara den biologiska mångfalden?

The examination of the adequate nature conservation methods in a natural reserve, to conserve a specific species and / or increase biological diversity is the subject of this study. This work is based on four species, that can be found during the Spring season, liverleaf, wood anemone, brimstone and woodpecker. The incidence and availability is studied and closely observed for these species in twenty forests, i.e. ten forests which are nature reserves and ten forests with the similar characteristics as the nature reserves habitat, but are not nature reserves in Gnesta mucipality, Södermanland. Measurements of the tree crown and the diameter of the tree trunks where noted to study how these factors could affect the outcome of the abundance and incidence of the four species.

Jag trivs bäst när havet svallar, och måsarna ger skri : En textanalytisk studie av biologisk mångfald i läroböcker

Biological diversity is one out of four dimensions, characterizing the subject of Biology ac-cording to the school curriculum. As a concept, biological diversity had its break through at the UN environmental conference in Rio de Janeiro in 1992, where the convention about bio-logical diversity, named CBD, was signed. According to the convention, almost all the na-tions of the world have engaged themselves to preserve the national diversity of species, in-cluding the diversity of genetics and ecological systems.This thesis focuses the biological diversity from the perspective of school books. The aim is to find out how the biological diversity is presented in biology books for students aged 12-15 years.In 1994, the current Swedish secondary and high school curriculum called LPO-94 was pre-sented. The biology books used in this study were published between 1994 and 2007, all of them exist in many editions and are published by three different publishers.The conclusion of the study is that all the biology books that were examined have reached different levels of the development in the field of biological diversity..

Utveckling av gran, Douglasgran, bok och tall under skärm av hybridlärk :

?Development of Norway spruce, Douglas fir beech and Scots pine with a larch shelter wood? is a report written by Per-Olof Magnusson. The thesis is a compulsory part of forest engineer program at ?Skogsmästarskolan?, SLU, Skinnskatteberg, Sweden. The purpose of this report is to describe and evaluate an experiment with hybrid larch (Larix x eurolepis) as shelter wood, and different tree species growth and survival depending on the density of the shelter wood. The experiment is conducted by southern Swedish forest research centre, faculty of forestry, SLU in Alnarp. The hybrid larch ought to be an interesting alternative to birch (Betula sp.) as shelterwood on suitable sites in southern Sweden.

Hästars behov av socialt umgänge- En studie om hur hästhållare i Laholms kommun uppfyller hästars behov av social kontakt

The problem with keeping horses with to little social contact has come to attention in a new regulation that comes into effect august 1st 2009. It states that horses? need of social contact has to be accommodated. That?s why it feels important to try to survey the horse owners? awareness about the regulation and its present fulfillment.

Förekomst av Chlamydia/Chlamydophila spp hos gris med och utan konjunktivit.

ABSTRACTChlamydia and Chlamydophila are species of a family of bacteria (Chlamydiaceae) that cause a range of diseases, including conjunctivitis, in a variety of animals including pigs and humans. Some species cause zoonotic disease. This study examined the occurrence of Chlamydiaceae in samples taken from the lower eyelid conjunctiva in pigs with and without conjunctivitis. The study was initiated based on a herd investigation aimed to examine the experienced increase of conjunctivitis in some finisher herds. This study was conducted as a case-control study, by collecting samples from 62 case pigs (16-26 weeks old) and an equal number of controls, from three herds in Uppland, Sweden.

Vad styr förekomsten av sälg och asp? : en studie av olika beståndstyper inom Hamra kronopark, Dalarna

Aspen (Populus tremula L.) and goat willow (Salix caprea L.) are two important tree species in the aspect of nature conservation. Due to the elimination of forest fires, a former negative attitude towards deciduous trees in forestry and a strong herbivore pressure, these tree species have been negatively affected during the last fifty years. The aim of this study was to investigate whether the occurrence of aspen and goat willow could be related to either human impact or to site properties, such as ground moisture and vegetation type. A side study included an inventory of a number of cyanobacterial tree lichens on aspen and goat willow in order to try to relate the occurrence of these lichens species to stand history and stand properties. The study was performed in Hamra State Forest in northern Dalarna. Nature reserves were compared with stands in managed areas.

Alternativ modell för miljöundervisning i dagens gymnasieskola - modellekosystem

Studier visar att dagens elever känner oro inför framtiden och de klimatförändringar vår värld utsätts för. Skolverkets nationella kartläggning utav miljöundervisning i skolan visar dock att cirka hälften av de tillfrågade gymnasielärarna inte bedriver någon undervisning i ämnet. Denna studie beskriver en alternativ modell för undervisning i klimatfrågor. Elever ges genom modellering av ekosystem möjlighet att fördjupa sin förståelse kring klimatförändringar i samband med exploatering av topp-predatorer. Detta är ett realistiskt problem då en mängd studier visar att dagens ekosystem utsätts för en mängd stressfaktorer, med ursprung i klimatförändringar, och att exploatering av topp-predatorer kan leda till konsekvenser med artutdöende som följd.

En jämförelse av sitkagranens (Picea sitchensis) och den vanliga granens (P. abies) produktion :

Sitka spruce (Picea sitchensis) is a tree species that have its natural distribution along the West Coast of North America, from Alaska in the north to northern California in the south. Sitka spruce is a typical coastal tree species that can reach heights up to 85 meters and occurs in single pure as well as in mixed stands. The main purposes of this study were to describe the Sitka spruce growing characteristics and the volume production in comparison to spruce (Picea abies). The possibility to predict future volume production by using prognosis tools designed to be used on spruce were also studied. The material that has been used in this study are permanent sitka trials established by the Faculty of Forestry fixed Sitka trials and also material gathered in this study. A literature study was also carried out in order to determine the Sitka spruce growing characteristics. Sitka spruce has a high adaptation and a high volume production on a broad scale of soil types. The tree species is a pioneer species that has a fast early growth and in combination with sharp needles it is less susceptible to animal browsing than spruce. The factor that is the single most limiting factor for where the Sitka spruce can be planted is frost. This factor can be limited by using plant material with a well-suited provenance. According to the literature, the Sitka spruce has an average total volume production that is between 20-40% higher than spruce.

Svampsamhällen och svampsjukdomar på åkerböna samt svamparnas inverkan på grobarheten

Broad beans are becoming a larger crop in Sweden. This is probably due to the current discussion about the cultivation of soya beans that are imported to be used as protein fodder. Broad beans are a good break crop in a small grain intensive crop rotation and works as a protein source for animals together with for example ley. At present little research has been done on broad beans and more knowledge is needed. This study is about fungal communities and diseases on broad beans and the impact of these fungi on seed germination.

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) in coastal areas of northern Sweden

Productivity of Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) was studied on 12 sites in coastal areas of northern Sweden. On each site, sample plots were placed in adjacent Norway spruce and Scots pine stands with similar ages in between. Basal area, tree height, Site Index, volume production, simulated maximum mean annual increment (MAImax) and tree vitality were compared for the two species. Average basal area at the time of measurement was 30.4% larger for Scots pine stands than for Norway spruce stands. The difference between the two species in basal area increment during the last 10 years was related to stand age.

Att bryta nacken av skammen : En studie om kvinnliga alkoholister och skam

The purpose of this study is to explain how shame can be experienced by women with the stigmatizing illness of alcoholism. Another aim is to illustrate how this shame can be affected in social interaction with others and by other circumstances. The following questions will be highlighted in this essay: How can shame be experienced by female alcoholics? What can affect shame in interaction with other people, from the view of female alcoholics? What other circumstances can affect the shame, from the view of female alcoholics?This study features interviews with women who have successfully gone through the process of rehabilitation from the illness of alcoholism, have a long going and stable sobriety and arecurrently part of the work force. The study also features interviews with therapists specializing in the field of addiction recovery and have considerable experience in their fieldof working with women suffering from alcoholism.The subject matters shame and stigma form the theoretical/analytical tools for this research.

Bok- och grankonkurrens i Sydsverige - markegenskaper och naturlig föryngring :

In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.

Inventering av flodpärlmussla i Fylleån norr om Gyltigesjön

Freshwater environments are threatened worldwide, of which many of the species associatedwith freshwater. In 2014, 243 freshwater mussels were on the international Red List. One ofthem is the freshwater pearl mussel, Margaritifera margaritifera, which because of itscomplex life cycle can be counted as an indicator of whether a stream is worth protecting. It's since the early 1900's in decline throughout their range. Sweden is counted as a core area which is why we have not only a national but an international responsibility to conserve the species.

Effects of brown bear (Ursus arctos) odour on the patch choice and behaviour of different ungulate species

The return of large predators to regions where they were previously extirpated has created a need for knowledge about their effect on prey species, not only their lethal but also their behavioural or risk effects. In this study the behavioural risk effects of brown bear (Ursus arctos) were tested on fallow deer (Dama dama), roe deer (Capreolus capreolus), red deer (Cervus elaphus), moose (Alces alces) and wild boar (Sus scrofa). This was done by using patches of fur to simulate the presence of the novel predator (brown bear), a novel nonpredator (reindeer (Rangifer tarandus) and no fur as control. These three treatments were then compared. The response variables measured were increased vigilance, decreased feeding time and change in patch use.

Vattensork och åkersork - skadegörare i svensk fruktodling

There are two species of voles that cause damage in Swedish fruit production: the water vole (Arvicola terrestris) and the field vole (Microtus agrestis). Both species make the most damage during the winter season. The water vole makes subterranean burrows and cause serious damage by gnawing on the tree roots. The field vole seldom makes burrows and gnaws the bark at the base of the tree trunk. In recent years there have been several reports about increasing vole damage.

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