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1033 Uppsatser om Species composition - Sida 21 av 69

Gallringsinventering från helikopter utrustad med profilerande laser och kamera för låghöjdsfotografering

Today Holmen Skog finds and selects suitable thinning stands using data on upper height and basal area. These figures are often based on basic forest data that has been updated with the help of growth prediction models. The problem is that these figures are not always correct. The aim of this study was to investigate if a combination of data from a profiling laser and a digital camera for low elevation photography, can be used for collecting data on number of stems per ha, tree species mixture as well as basal area weighted mean height and upper height for stands. The possibility to use these data to assess the need for thinning cutting was also investigated.Laser data and aerial photographs were collected from a helicopter operating at an approximate height of 100 meters.

Lactobacilli in the gastrointestinal tract of dog and wolf : isolation, identification and characterization of L. reuteri

Since the first wolf was taken as a companion animal a lot have happened with the biology of these animals. Is it possible that changes in the gut microbiota of the domestic dog are involved in the increasing numbers of animals with gastrointestinal disorders? Probiotics have been proven to promote the immune system of dogs by increasing concentrations of neutrophils and monocytes, decreasing the fragility of erythrocytes and increasing the serum IgG concentrations. Probiotics have also been shown to improve the fecal consistency, fecal dry matter and defecation frequency of dogs. The aim of this study was to find out if the bacterial counts in the gut of dogs differed from the gut of wolves, with the focus on lactobacilli.

Könsselektering av spermier från lantbrukets husdjur

Millions of preselected progeny have been born since the development of The Beltsville Sperm Sexing Technology 1986. The method is based on flow cytometry and sorting is done on the basis of DNA difference of the X- and Y-chromosomes. Preselection of progeny provides an opportunity to obtain genetic gain and increased production as well as increased animal welfare and decreased environmental impact. However, the method is associated with low fertility, high costs and uncertainty whether the sorting process contributes to DNA damage and thereby results in genetically impaired progeny. Today, sex sorted sperm is only commercially available in the bovine industry, due to the fact that bull sperm is more suitable for selection than sperm from other species.

Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?

Fungi are everywhere around us and recently, there has been an increased interest in their role and importance in the forest. The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials. Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate. Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry. A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects. The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored. Researching fungi knowledge and interest, a survey was distributed to five groups of people. The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.

Social struktur och dominans hos hund

The dog (Canis lupus familiaris) is the first species ever domesticated. They can develop a close bond towards other dogs, almost like a relationship among siblings, which can be a high valuable resource for good relations and cooperation?s. Dominance in dogs is sometimes used to explain undesired behaviors and explained as a personality trait. Dominance though, is not a trait in a dog or a source for undesired behaviors, but can rather be explained as a relationship between individuals, were one of them receives more submissive signals from the other.

Bildandet av naturreservat : uppföljning och klimatanpassning

AbstractWe are facing a century of rapid change in climate, with significant challenges in managing the impact of changes in living conditions for plants and animals. We can already see the responses of species through changes in phenology and spatial distribution, which may change ecosystem structure and function, with subsequent effect on ecosystem services and biological diversity. In Sweden, between 2005 and 2010, the red-listed species has increased by 13 % and similar trends can be seen across the world, making it difficult to attain national and international environmental objectives of preserving biodiversity. One way to reduce the loss of biodiversity is to protect nature from exploitation by allocating valuable areas as nature reserves, but climate change affects protected areas just as much as other landscapes and therefore requires elaborate systems of protection to facilitate species' survival. The paper has examined  how the decisions and management plans for nature reserves in Sweden have been followed-up and whether they are climate adapted or not by examining 30 nature reserves, classified as newly formed (2012), recently revised (2009-2011) and older (1977-2007) reserves, and assessed what is in the decisions and management plans for follow-up, revision, long-term goals and documentation.

Vilken preferens har tjockskalig målarmussla (Unio crassus) för bottensubstrat och vattenhastighet i Storån, Östergötland?

The thick shelled river mussel (Unio crassus) has a fragmented distribution in southern Sweden. It is a threatened and protected species. In both the Swedish red list and the IUCN Red List of Threatened Species Unio crassus is classified as Endangered (EN). Causes for this classification are for instance differentiated bottom substrate and deterioration in water quality. In this study, habitat preferences of Unio crassus were investigated to assist in future restoration work.

Healthier vegetables through temperature stress? : a review of Brassica oleracea

The objective of this report is to present a review of the studies which has been carried out up to days date concerning how temperature affects vegetables physiologically when it comes to their health inducing as well as quality reducing features. The essay therefore starts off with defining what is meant by the terms health promoting and quality reducing features. It then moves on to describe how different subspecies of Brassica oleracea, that is to say vegetables such as broccoli, cauliflower, Brussels sprouts and kale, is affected by temperature. B. oleracea was chosen because the species contains several commercially interesting subspecies and therefore provides a broad field even though only one species is assessed.

Biotopskydd av stenmurar : Skäl för dispens

Stone walls in agricultural land are incorporated in the general protection of biotopes. They are protected because they provide a habitat for endangered species. Therefore it is illegal to carry out proceedings in an area that is included in the protection of biotopes. In order to do that, exemption is needed which can only be granted if there are special reasons. The essay stipulates what these special reasons are.In an exemption errand the interest for nature conservation must be weighed against a public or a private interest.

En studie av Helleborus :

This work describes the genus Helleborus both from a general point of view, and with individual descriptions of 17 species. The intention is not to make a complete description of the genus, but rather to give an overview and an introduction into the world of Helleborus. A separate chapter lists a few pests and diseases attacking the genus, followed by a brief summary of propagation methods and breeding of the genus. Finally, there is a short discussion of thoughts about the genus and its future use..

Picea mariana ((P. Mill.) B.P.S), P. abies (L.), Pinus contorta (Dougl.) och P. sylvestris (L.) : en jämförelse av produktion och potentiell kvalitet hos försöksbestånd i Jämtlands län

Swedish forests are dominated by just two conifer species Norway spruce and Scotch pine. They are not able to achieve the highest possible production or fulfill industry demands for raw materials. The introduction of exotic conifers can potentially meet these shortcomings and present a relevant solution. This study was conducted in a block experiment with ten blocks planted in 1987 by SCA in North Sweden. The objective of the block experiment was to study if Black spruce is an appropriate alternative to Lodgepole pine, Norway spruce and Scotch pine on different site classes.

Jaummuov?rrie blomster?ng: en v?rdering av artrikedomen och dess kulturhistoriska roll

The thesis "Jaummuov?rrie Flower Meadow: An Assessment of Species Diversity and Cultural History," provides a detailed botanical examination of Jaummuov?rrie flower meadow in the Ammarn?s area, focusing on its biodiversity and cultural significance. The study aims to evaluate the species richness of the meadow and explore its role in the cultural heritage of the region. In addition to its ecological importance, the thesis delves into the cultural history of Jaummuov?rrie flower meadow, tracing its significance to the local community and traditional practices.

Parasitering på en expanderande art : har kartfjärilen undkommit sina naturliga fiender?

Warmer climate is a driving factor to species expansion northwards. Expansion to new areas can result in escape from natural enemies, resulting in reduced levels of mortality and thereby potentially increasing the rate of expansion. The most important parasitoid species attacking butterfly larvae belong to the families Tachinidae, Ichneumonidae and Braconidae. The aim of this thesis was to investigate parasitism and difference between populations in established area and newly colonized area for the European map butterfly, Araschnia levana, in order to examine if the butterfly has escaped from some natural enemies. In 1982 the first European map butterfly was observed in Sweden and has now established up to middle Småland.

Tungelsta med trädgårdstema :

In this project, an area in the small town Tungelsta south of Stockholm, is in focus. Tungelsta is placed in the municipality of Haninge and it is for the planning department on the municipality, this project is made. The task is to compose an arrengement of buildings and open spaces for a 50 hektar area. Today the area is consists of agriculture fields and forests. The area is placed near the railway station, in the city centre of Tungelsta, which makes it interesting and important to work with. There are different opinions about the future plans for the area.

När trädens rotsystem får bestämma : En intervjustudie med en grupp yrkesverksamma inom anläggning av hållbara gröna miljöer.

ABSTRACTThis pilot study examines the knowledge about tree root systems amongst five treeplanting professionals. The aim is to find out the professionals? collective knowledge ofthe nature of root systems of various trees used in green areas. Furthermore; to explorehow the professionals adapt landscaped green areas to the tree root properties in asustainable manner. Questions: Which tree species have special root properties toconsider and how do the professionals utilize this knowledge? And: How do theprofessionals in general adjust planting according to the root systems of trees in areas tocreate sustainable green environments?Interviews with the professionals were performed.

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