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1033 Uppsatser om Species composition - Sida 8 av 69

Evaluation of an ectomycorrhizal macrofungi as an indicator species of high conservation value pine-heath forests in northern Sweden

Since the 1950s, the development of modern rotation forestry in boreal Fennoscandia has resulted in a severe reduction of older forests, and a high degree of fragmentation among the small patches that remains of old forest. In Sweden, when performing conservation value assessments in order to identify and preserve the remaining forest habitats, the government authorities use to a significant extent a set of indicator species that indicate habitats of high biological conservation value. One species considered to indicate high conservation values in pine-heath forests is the red-listed ectomycorrhizal (EM) macrofungi Sarcodon scabrosus (Fr.) P. Karst. In the present study, the validity of using S.

Upptryck : En jämförelse mellan RIDAS och internationella riktlinjer

Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).

F?gelv?gen och f?gels?gen. En multi-proxy analys av m?nniskans relation till f?glar under den yngre j?rn?ldern i Mellansverige

Prior research in human bird relations is relatively small and discussion about bird ecology in relation to humans is largely not discussed. The study means to understand how a difference in usage of birds and symbolization of a bird occurs. This will be answered through analysis of two bird species. The study uses three different sources of material to conclude its answers. The sources are graves with bones of predatory birds, material culture representing bird motifs and historical sources discussing mythology.

Får är får och get är get : utvärdering av osteologisk metod med stöd av arkeogenetik

The difficullty to distinguish between sheep and goats is a well-known problem in archaeology and osteology. Distinguishing sheep and goats in archaeological animal remains takes time and time is often limited for osteologists. Because of this difficulty osteologists and archaeozoologists often use the term sheep/goat or ?ovicaprids? in their analytical reports. But even if the term sheep/goat comprise both species, this is often not the case when archaeologists and osteologists interpret and present archaeological findings.

Vad vet gymnasieelever om betygskriterierna och kursplanen i Idrott och Hälsa?

The Scanian woodfences has been determined by two mainly elements: Scania's composition of tree species, with a large element of deciduous forest, and the local building tradition which has more in common with the European continent than the Swedish tradition. By examining responses from ethnological question lists deriving from the first half of the 1900s, combined with literature studies, I have been able to deepen and broaden the knowledge behind the various fencing design. In addition I ?ve constructed maps which could illustrate their historical geographic distribution.I have come to the conclusion that there was three main types of woodfences that was most common until the barbed wire was introduced in the early 1900s and later on replaced the elderly woodfences. Common for the three main types is that the base material was made out of Juniperus communis, this largely because of its durability against rot.

Potentiella arealer för ökad virkesproduktion i norra Sverige genom skogsodling med Pinus contorta var. latifolia, Larix sukaczewii, Abies lasiocarpa, Populus × wettsteinii och Picea mariana

Sweden is a country with few native tree species. According to Govt. 2007/08: 108, exotic tree species may be seen as an opportunity to increase the growth of tree volume in Sweden. Potential areas where explored In this work for cultivation with Pinus contorta var. latifolia Engelm., Larix sukaczewii Dylis, Abies lasiocarpa (Hook.) Nutt., Populus × wettsteinii Hämet-Ahti (tremula x tremuloides) and Picea mariana (Mill.) Britton et.al.

Styrelsens unika kompetensbehov : En studie av kompetensförändringen i styrelsen

Background: The board of directors is a key player in corporate governance. Their role is to ensure that the corporations are run with the interest of the shareholders as the main focus. In the beginning of the 21st century, a survey was made about the confidence of the Swedish business community and in which criticism was directed to the board of directors. The boards were deemed inadequate in their function and were often solely composed by members with similar experiences and competence, therefore lacking in diversity. In order to improve the competence and work of the board of directors, the Swedish code of corporate governance was introduced and its recommendations comprehend the boards? size and composition.

Valfrihetens konsekvenser : medvetna och omedvetna skolval

This study illuminates chosen parts of the present opportunities, in the Western World, for parents and children to choose which school the child will attend (freedom of choice), along with possible consequences that may follow. My research questions are: 1) Do tendencies show that freedom of choice leads to increased segregation, and if that is the case, how is it manifested and does it matter? 2) What relations between the student composition of schools and teachers' expectations and attitudes toward students are there? 3) Do the results from previous studies match with the result from my interviews? The methods used for answering the questions are literature studies and interviews made with six teachers who are working in two upper secondary schools in the northern part of Sweden, i.e. three from each school.The result shows that freedom of choice, regarding schools, seems to lead to student compositions that contribute to increased segregation in societies. It leads to more homogenous student compositions, in the form of ethnicity and social class, in schools in general, with consequences like different expectations and attitudes among teachers depending on the status of the composition.

The influence of active bomas on habitat choice of the common warthog (Phacochoerus africanus)

The common warthog (Phachocoerus africanus) is a relatively long-legged pig with noticeable curved tusks, a short neck and three pairs of facial warts. It has four recognized subspecies. The common warthog is a non-migratory ungulate living on the African savannah. It is a hindgut fermenter and predominantly dependent on high-quality foods. It prefers open areas for grazing but use bushes for cover.

Fermenterat blötfoder till gris

The purpose of this literature study was to examine what kind of composition fermented liquidfeed can have, what a desired composition is and possible advantages and disadvantages onhealth and growth performance of the pig. A well fermented liquid feed is characterized by a lowpH (.

Optimization and validation of a triplex real-time PCR assay for thermotolerant Campylobacter species associated with foodborne disease

The genus Campylobacter is globally recognised as the leading bacterial cause of human foodborne gastroenteritis. Every year around 8000 Swedes are infected by Campylobacter. Most people are infected by thermotolerant Campylobacter species, commonly C. jejuni and C. coli.

Brandrelaterade insekters lokala artrikedom i förhållande till olika miljövariabler : Fokus på betydelsen av konnektivitet på brandfält i boreal skog i Västerbottens län

The last century, forest fires have decreased in frequency due to efficient fire-suppression along with the growth of the industrial forestry. Since 1990, fire has been reintroduced under controlled forms to recreate burnt habitats. Many species that are dependent on, or benefits from, forest fires have increased since fire was reintroduced. The importance of connectivity is often addressed in ecological research. This is particularly important for species dependent on short-lived habitats such as burnt forests.

VILKEN STRANDVEGETATION BIDRAR TILL DET ORGANISKA MATERIALET I KUSTN?RA SEDIMENT? Kols?nkor/k?llor, nedbrytbarhet och eDNA sp?rning

Coastal sediments are important carbon sinks, storing organic matter and thereby helping to reduce the amount of greenhouse gases in the atmosphere. However, they can also act as carbon sources if the deposited organic matter decomposes rapidly, contributing to increased greenhouse gas emissions and global warming. Rapid decomposition partly depends on the degradability of the material itself. In this literature review, I examine which coastal plant species dominate different locations along the Swedish coast, based on coverage data from the ClimScape project (www.climscape.se). For the most dominant species, I investigated the type of organic matter they may contribute to the sediments and based on those results I qualitatively assessed which sites that may function as carbon sinks or sources.

Biologisk mångfald i små grönområden : Inventering av insekter och fåglar i bebyggda områden i Solna kommun

All over the world the urbanisation increases at the expense of green areas. Many plants and animals are endangered today because their habitats gets smaller or disappear. The green areas that are left in city centres and suburbs are often small and surrounded by roads and buildings. Despite this, several studies have shown that these small green areas may house large biological diversity.This project aims to study the biological diversity in small green patches in residential areas. The study has been carried out in Råsunda in Solna municipality (Stockholm county) during the period May?July 2006.Three equivalent areas (5000?10 000 m2) with quite many old oaks were chosen for the study and inventoried for birds and saproxylic insects.

Biologisk mångfald i små grönområden : Inventering av insekter och fåglar i bebyggda områden i Solna kommun

All over the world the urbanisation increases at the expense of green areas. Many plants and animals are endangered today because their habitats gets smaller or disappear. The green areas that are left in city centres and suburbs are often small and surrounded by roads and buildings. Despite this, several studies have shown that these small green areas may house large biological diversity.This project aims to study the biological diversity in small green patches in residential areas. The study has been carried out in Råsunda in Solna municipality (Stockholm county) during the period May?July 2006.Three equivalent areas (5000?10 000 m2) with quite many old oaks were chosen for the study and inventoried for birds and saproxylic insects.

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