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721 Uppsatser om Biological diversity - Sida 17 av 49

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.

Nakna sanningar från Amerika : Moderniserings- och kulturperspektiv från svensk-amerikanska berättelser

The purpose of this study is to shine a light at the Swedish americans impressions and attitudes against the American society from the perspective of modernization and cultural attributes. This, with a reference frame of the deeply politically rooted European conception of America as a threat to the cultural well being, and as a thriving materialistic and progress bound constitution.The result shows that the attitudes against America in the descriptions were not all comparable with the conception that was conducted in Europe. However, the experiences altered whereas the study attends two different periods of time. The experiences differenced due to the growing exposure to cultural diversity and a modernization that grew faster in America than anywhere in the world. Not to mention the change of experiences and expectations that was with brought from a changing atmosphere in Sweden.

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.

Jaktens betydelse för Södermanlands landskap : Hur viltvård kan påverka variationen av lövträd och buskar

The fragmentation and reduction of deciduous forests in Sweden is threatening many species. Particularity worrying is the loss of broad-leaf trees, since a diversity of species is often associated to them. Today many deciduous trees are situated along the border between forested and open areas, and these small fragments can be important for biodiversity.The aim of this study is to analyze if wildlife management can affect the variation of deciduous trees and bushes in the landscape. In brochures and literature Svenska Jägareförbundet (the Swedish Association for Hunting and Wildlife Management) recommend hunters and landowners to promote deciduous trees ? often broad-leaf trees ? as wildlife management measures, while the Swedish forestry laws can be sensed as unclear regarding the treatment of these trees.Five properties in Södermanland, Sweden, were chosen as study areas and inventoried in respect of trees and bushes in September 2013.

Ifrågavarande kronopark skall benämnas Skatan : en skogshistorisk analys av Ekoparken Skatan

People have utilised and influenced the boreal forest for many centuries. Prior to the industrial revolution during the 19th century, however, human use primarily only had a low impact on the forest. When the timberfrontier swept over the country, the Swedish forests came to change for ever. The study site for this thesis is situated in the northern part of the county of Västerbotten, Sweden, and has previously been a National forest. Today the area is an ecopark and the land is owned by the forest company Sveaskog.

Respiratorisk sinusarytmi under påverkan av emotionell stimuli: en studie av emotionell påverkan från biologiska och ickebiologiska hotrelaterade bilder.

In this paper respiratory sinus arrhythmia (RSA) was examined in relation to two kinds of threatening pictures, biological and nonbiological. Based on the results of prior research the hypothesis was claimed to note a difference between the two types of pictures regarding RSA and gender differences regarding cardiac activity due to the emotional stimulus. ECG and respiration were collected from 36 adults, 17 women and 19 men. There were no significant relationship between the different types of threatening pictorial stimuli, and no significant effects of gender were found. The results support some of the prior research on the topic but are in conflict with other.

Skånska småvatten nu och då : jämförelse mellan 1940, 1980 och 2000-talet

Populärvetenskaplig sammanfattning: Småvatten i form av dammar och våtmarker har en viktig funktion i både den terrestraoch akvatiska miljön. De fungerar till exempel som buffert för näringsämnen från attflöda ut i havet och dem ökar den biologiska mångfalden bland växter och djur.De flesta antropogena småvattnen har sitt ursprung från 1800-talet och 1900-taletsbörjan, då näringsrik märgellera grävdes upp från åkrar och hålen på åkrar fylldes uppmed nederbörd. I samband med jordbrukets effektivisering så jämnades många avdessa märgelhålor och antalet småvetten minskade avsevärt. Sedan mitten på 1980-talet har småvatten och våtmarker uppmärksammats i en rad olika miljöprojekt iSkåne.Syftet med denna magister uppsats i ämnet Naturgeografi är att uppskatta samt att i ettlängre perspektiv få reda på hur dessa småvatten förändringar skett de senaste 60 årenoch vilka effekter det haft för omgivningen. Metoden som användes var fjärranalys ikombination med fältbesök samt skärmdigitalisering i ett GIS.

Klassifikation och ordning

This master thesis concerns the relationship the librarianhas to the libraries classification system. The system itselfis made by librarians for librarians and is only used bylibrarians. This raises the question of how the librariansrelate to their own system to create order. The empiricalmaterial consists of five in-depth interviews with librarians.Two theoretical approaches were used in the analysis of thematerial with one focus on the librarian?s professional rolland the other on the postmodern theories about humansneed for order.

Ytterväggar och bjälklag för flerbostadshus

The thesis demonstrates protection solutions that can be suitable for a camp during internationalmissions in order to resist complex threats. The threats could consist of small arms, machineguns,RPG 7, anti armour missiles, mortar, artillery, HPM-weapons, car bombs, biological and chemicalweapons as well as sabotage and theft. It?s not the technology itself that makes the threat scenariocomplex it?s the way the opponent acts during the operations. The opponent acts usually incivilian clothes and therefore he is difficult to distinguish from other civilians.

Gott och blandat ska det vara! : En studie om mångfald och dess effekter i arbetslivet

While designing an intranet for people with mobile work there are things you have to consider. This thesis is aim to bring understanding to the difficulties involved in these kinds of situations. Our focus is to develop ideas that motivate the assistants to use the intranet. We have looked into the profession of personal assistants and wish to highlight their problems to access the intranet. And we will as well demonstrate their needs for communication.

Ett verktyg för konstruktion av ontologier från text

With the growth of information stored over Internet, especially in the biological field, and with discoveries being made daily in this domain, scientists are faced with an overwhelming amount of articles. Reading all published articles is a tedious and time-consuming process. Therefore a way to summarise the information in the articles is needed. A solution is the derivation of an ontology representing the knowledge enclosed in the set of articles and allowing to browse through them. In this thesis we present the tool Ontolo, which allows to build an initial ontology of a domain by inserting a set of articles related to that domain in the system.

A resource based view of productivity, firm growth and technical management tools : a case study of Swedish large-scale farms

The past and ongoing structural change in Swedish agriculture has led to an increasing number of large-scale farms. The biological factors associated with large-scale farming operations may cause increasing variability, risk and reduced yields due to sub-optimal timing and management of field operations. The theory of economies of scale suggests that largescale production may benefit from lower costs due to scale efficiencies. Thus, large-scale farms may face cost reductions in terms of long term inputs factors, e.g. agricultural machinery.

Den virtuella mötesplatsen : Om de ungas användning av datorer och Internet i vardagen

The purpose of this study was to illustrate how children of the "digital generation" used their computers in their everyday practice. The important in the study was children's perspective on computers interactions and communications in a digital arena.An essential item about understanding children's way to think about computers was to let children themselves speak by taking part in the study, because children's voices are seldom heard in public. The empirical material used was interviews with sex children between 13 and 15 years old. My method was qualitative.The main results showed that social relations are very important for children. The Internet gives children access to an arena where they are able to make new contacts with others as well as transcend their biological as their physical identity.An important accepts for the children in the study was the option to be anonymous.

Retention of stumps on wet ground at stump-harvest and its effects on saproxylic insects

Low stumps represent on their own up to 80% of the dead wood remaining on clear cuts and therefore supply suitable habitat for saproxylic insects i.e. insects depending on dead wood for their survival. Recent stump harvesting activities threaten this substrate of ecological importance and increase the anthropogenic negative impacts on these species. Because of technical and environmental reasons (nutrient leakage, erosion) guidelines for stump harvesting recommend to retain stumps standing in wet parts of clear cuts. However, stumps in wet positions might not be a satisfactory substrate for saproxylic insects and therefore might not be as much used as stumps in dry positions.

Könsskillnader i betyg, Ronneby kommun -Ett implementeringsproblem?

This study was carried out in Ronneby municipality during May 2006. I chose to compare three senior schools with regards to the implementation of objective orientated directives based on the teachers understanding of the task, motivation, resources allocated and their significance for the disparity between boys? and girls? grades.I carried out nine in-depth interviews: three at each senior school. From the interviews it emerged that teachers perceive objectives differently from parents and students. Teachers claim that they understand the directives but say that they lack the resources.

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