Sök:

Sökresultat:

2172 Uppsatser om Identified species - Sida 1 av 145

Species diversity and geographical distribution of Fusarium species on winter wheat in two regions in Sweden

Various Fusarium species causes some of the most common cereal diseases worldwide. Besides the yield losses that can be a result of these diseases, strains from several Fusarium species can produce mycotoxins, some very toxic. The aim of this study was to investigate which Fusarium species and how many that occurred in winter wheat grains from Mälardalen and Kalmar län, if there was any difference in the distribution of Fusarium fungi between the regions and the potential within species to produce mycotoxins belonging to the group trichothecenes. Winter wheat grains collected in 2009 from ten fields (unsprayed plots) in the two regions were analysed for Fusarium species. PCR was used to amplify the TEF region where after the samples were sequenced.

H?RNERVMOSSANS P?VERKAN P? LJUNGHEDENS ARTM?NGFALD: En f?ltstudie fr?n Sandsj?backas naturreservat

Campylopus introflexus is a moss species that originates from the southern hemisphere and has spread worldwide during the 20th century. Today it is classified as an invasive alien species in many countries, and it has been seen during inventories that it has become widespread in Sweden as well. The purpose of this essay is to contribute to new knowledge about how this moss affects species diversity on Calluna heathlands in Sweden. The study includes both fieldwork and an analysis of scientific literature on the subject, and the question that is answered is if C. introflexus has an impact on species richness in the heather peat.

F?RS?LJNING AV OCH INST?LLNING TILL FR?MMANDE V?XTER I TR?DG?RDSBRANSCHEN

Alien plants that have intentionally been introduced to an area for cultivation in public or private gardens constitute the primary pathway of introduction for invasive alien species that spread into nature. Garden owners want species that have satisfying characteristics, these characteristics are often also linked to plant invasiveness. Thus, the horticulture industry plays an important role by making scientifically based decisions and phasing out invasive plants and replacing them with alternative species with satisfying characteristics, but low risks of becoming invasive. This thesis aimed to examine the sale of and the attitudes towards alien plants in the horticulture industry in Sweden. Alien terrestrial plants identified to have a severe risk, high risk or potentially high risk of spreading and becoming invasive according to ArtDatabankens assessment, were examined to see if they were for sale.

Gäddan & fisket i Ringsjöholm : en osteologisk metodstudie i säsong & bevarande

This paper presents the results from an osteological method study of the Ringsjöholm fishbone material. Ringsjöholm is located in Scania, southern Sweden and is 14C dated to 5960-5200 B.P. The aim of this paper is to critically analyse methods used on fish bone material in estimations of season. Three different approaches were used to estimate the fishing season at the Ringsjöholm settlement; 1) Identified species, 2) size estimations of the pike based on Enghoffs (1994-95) regression formulae of os dentale, and 3) growth rings of the pike vertebrae.The Identified species and the size estimations of the pike points to the fishing being active both during spring and summer. Growth rings analysis of the pike vertebrae didn?t give any quantitative results because of fragmentation.

Osteometriska Mätningar : För artbedömning av får, get och svin utifrån mått av revben

Ribs from sheep, goat and pig are rarely assessed  to species due to the fact that they are very similar in their morphology and size. The ribs are instead considered unidentifiable although it is possible to see what kind of bone it is. If these ribs would be identified to species not only would species assessment degree of archaeological source material   increase, the relationship between meat-rich and meat poor regions would change.To find out whether there are morphologically measurable differences between sheep, goat and pig ribs, three measurement points on each rib has been defined and measured. At each measurement point two measurements were measured, one medial-lateral measurement and one cranial-caudal measurement. The ratio between the medial- lateral measurement and the cranial-caudal measurement was calculated for each point.

Effekter av landskapets sammansättning på humlearters förekomst

The species in the genus bumblebees (Bombus) are important pollinators. In the world there are 250 bumblebee species and there are 34 species in Norway. The purpose of this study is 1) to assess changes in the species composition of bumblebees in twenty different places in Norway that have been inventoried first one time between 1939-1960 and the second time in 2012, and 2) to relate species richness and distributions to current landscape composition with the aid of orthophotos. In this study, I have used regression analyzes on the different bumblebee species that were present or absent at the inventory, using the premises of the following variables: low or high altitude, latitude, longitude and seven different types of land use (farmland, building/plots, open land/pasture, forest, wetland and open or snow-covered ground above the tree line) to see if there was any relationship between each species and the different variables. I have not analyzed what the landscape looked like at the first inventories and therefore we cannot say whether it has changed and if that is why species number has decreased. This would be interesting to study further and to see if there is any relationship between landscape changes and bumblebee?s species decline.

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.

Samgång av olika arter på svenska djurparker

Zoos currently aim at keeping animals in as natural habitats as possible, since they havegone from displaying exotic animals to working with conservation of endangered species.It is therefore more common that zoos keep groups composed of two or more species in thesame enclosure. The aim of this report is to study why and how different species are held atzoos. Species in the wild can interact in different degrees depending on season andresources. When species are held together at zoos the space can be more effectively used,the animals increase their activity and the visitors increase their learning. Mixed speciesenclosures involve more work and risks of injury.

Didaktiska arter

The study intends to find easily recognizable indicator species for water quality in the constructed wetland of Flemingsbergsviken. The study is relevant since indicator species can be difficult to determine for common people. Easily recognizable indicator species could improve dialogue between the scientific community, administrative authorities and the general public. Such species could be used in education systems, associations or in information campaigns. Therefore, I have chosen to refer to these species as didactical species.

Fältskiktsarter i naturlika planteringar : vilka råd kan ekologer ge?

This paper appeals to professionals working with green questions. It intends to create a discussion about which plant species that can be established in a fieldlayer of a naturelike planting on fertile agricultural land. To initiate the essay, a studie of which values that can be connected with an establishment of a fieldlayer was performed . A part of Tor Nitzelius Park in Alnarp, a so called naturlike planting on fertile agricultural land, was used as a model for the choice of species. With the aid of soil values, photos and a list of current species, interviews with four ecologists were performed.

Bestämt eller obestämt? En kontrastiv jämförelse av ett antal engelsk- och kinesisktalande inlärare av species i svenska.

Specialarbete, 15 hpSvenska som andraspråk, fördjupningskurs SSA133Vt 2012Handledare: Hans LandqvistExaminator:.

Hälsostatus hos abborre (Perca fluviatilis) i Gumpfjärden, Bottenhavet :

Perch (Perca fluviatilis) is a very popular fish in Sweden and it is common in Swedish waters. In some areas along the Swedish coast the perch population has decreased. It is therefore important to get a view at the health status of perch. During April, July and August of 2008, a total of 346 perches were caught in the Gump Bay in the Botnian Sea. The fish were mainly caught by net but also by rod.

KLIMATTOLERANS HOS URBANA TR?D I G?TEBORG: Analys av klimatgr?nser och framtida klimathot

Urban trees contribute significantly to our society. By providing ecosystem services and a habitat that other urban species and ecosystems depend on, both biodiversity and the people in the city benefit. Some characteristics that the trees possess include functioning as biological filters for the atmosphere and water, as well as positively impacting people's mental health. However, urban trees are challenged by stressors such as pollution and a drier environment, making them particularly sensitive to climate change. The goal of this study was to estimate the expected magnitude of climate change in Gothenburg and compare it with the current urban species' natural climate boundaries to understand the extent of the climate threat and which species appear to be most at risk.

Artrikedom av kärlväxter i övergivna och restaurerade hagmarker : betydelsen av igenväxningsgrad och tid sedan igenväxning började

Continuously grazed grasslands have remarkably high plant species diversity. In Sweden this type of habitat has declined for the last two centuries. Changed land use has caused habitat fragmentation and loss of habitat quality. This has caused a great number of plant species to end up on the verge of extinction. To try to save this unique habitat and the species that are tied to it, lots of resources are laid on restoration of abandoned grasslands. In this study, plant species richness of continuously grazed, abandoned and restored grasslands were related to degree of overgrowth, time since overgrowth started and rate of overgrowth.

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.

1 Nästa sida ->