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254 Uppsatser om Density - Sida 16 av 17
Flygbildsanalys av trädskiktets status efter brand : en metodstudie
During the past years fire has been identified as an important factor for nature conservation in the forest landscape. To accurately quantify the size of a burnt area is obviously important, but also to quantify the degree of fire damage to the tree canopy. Such data are important for assessing the conservation value, and to support planning and management of the burned area in the future.
I have examined how to estimate the status of tree crowns after fire from interpretation of aerial photographs. This is possible because fire changes the structure of tree crowns and this influences the colours in aerial photographs by spectral reflection.
Included in the study are four areas, three of which burned in 2005 and one in 2006.
Allanblackia stuhlmannii ? a tree under current domestication: what are the soil requirements?
Allanblackia is a genus of trees that grows in the rainforests of West, Central and Eastern Africa. Its big fruits contain seeds very rich in oil which has been used by
local communities for cooking and making soaps. The native stands are threatened by overexploitation and the demand for the oil is much greater than the supply.
Domestication programs, aiming at introducing the trees to small holder agroforestry systems, have been started for some of the species. The main aim of this study was to investigate the soil requirements of Allanblackia
stuhlmannii in terms of chemical and physical parameters, as revealed by the soil conditions in native stands. Another aim was to see if these varied along an altitudinal transect.
Effekter av transport och buller på grisars aktivitet samt aggressiva interaktioner i väntan på slakt :
During pre-slaughter handling of pigs the animals are often subjected to methods that induces stress and are a threat to the wellbeing of the animals, such as mixing of groups, loud noise and transportation. A new law will be implemented in 2006 in Sweden that prohibits mechanical noise exceeding 65 dB in abattoirs. The purpose of the research presented in this paper was to examine the effects of noise and transportation on pig behaviour. The activity and aggressiveness of the pigs were examined with behavioural studies during transportation and during three different noise levels: 55, 75 and 95 dB.
Before the noise treatments took place the groups were mixed and half of them were transported for approximately 2 hours. In the study 432 pigs were used.
Karaktärisering av äpplesorter : för framställning av juice och cider
The purpose of this study was to evaluate which apple cultivars are best suited for production of juice and cider. The study was limited to 41 cultivars. Common as well as uncommon apple cultivars were selected from available cultivars in the cold storage at Balsgård, Department of Horticultural Plant Breeding and Biotechnology, SLU.The practical part of the study consisted of the apples being pressed, and then the juice characteristics being assessed by appropriate criteria and methods of analysis. The analyses consisted of measurment of soluble sugars with a refractometer (Brix), titration of total acidity, determination of total phenolic content with a spectrophotometer, estimation of alcohol content by Density meters and qualitative taste tests.The study did not account for different maturity of cultivars. Different apple cultivars were pressed on separate occasions, before and after Christmas 2010.
Att återställa en naturlig ordning : skogshistoria och restaureringsbränning i Långsidbergets naturreservat
During the late 1800s fire suppression became increasingly effective in northern Sweden which led to decreased areas of fire-disturbed woodland and successive changes in the structure of forests. In the long run this can pose a serious threat to fire-dependent and fire-favored species. Today some fire-prone forest reserves are burned as a nature conservation act. Often partial cuttings are made before burning, with somewhat different motives. The purpose of the study in Långsidberget nature reserve was to give a general picture of forest history and its affect on today?s forest condition, and to show how partial cuttings affect burning conditions and results.
Långsidberget is located close to areas that were colonized during the Middle Ages.
Skaftslamkrypa (Elatine hexandra) i Bolmen, utbredning, tillväxt, reproduktion och styrande faktorer
The plants in the genus Elatine are characteristic for oligo and mesotrophic lakes. This study focuses on Elatine hexandra one of the four species in Sweden. It is stated as vulnerable by the National Environment Agency and a conservation plan with guidelines to preserve the plant in Sweden is under preparation. There have been a few previous studies investigating this plant in other countries but this is the first one for Sweden. The aim of this study was to investigate the distribution, growth and reproduction of E.
Höjdmodellering med laserdata : Studie av Kärsön, Ekerö med fokus på upplösning, datalagring samt programvara
The New National Elevation Model (NNH) is a new high-resolution digital elevation model (DEM) of Sweden from airborne laser scanning. It creates many new opportunities, particularly in the area of flood mapping. NNH is provided by Lantmäteriet in two formats, both in raw LIDAR (Light Detection and Ranging) data and in grid format with two meter resolution. These alternatives have advantages and disadvantages and the aim of this thesis research is to identify these. One of the focuses of the study is data storage and thus data structure analysis, resolution and storage facilities. The research questions are:Why and in what context the different NNH-products from the National Land Survey are used (DEM 2+ or point cloud)?What constraints and opportunities are created by the different options, mainly in terms of different software, resolution, and data storage?The study area is Kärsön in Ekerö municipality located in Stockholms län and has an approximate area of 25 square kilometers. The study is divided into two parts. The first objective is to identify the consequences of using different software to create DEM from pointcloud compared to the DEM2+ model. Height models with a two meter resolution are created in FME and ArcGIS. The models are then compared with the grid from Lantmäteriet, created in TerraScan. The second objective is to examine the impact of the change in resolution, both the storage aspect and both the accuracy aspect. Inverse Distance Weighted (IDW) is an interpolation method which in previous studies proved to have the best results on high resolution LIDAR data. This model was tested and compared with a model from FMEs built-in function and the model from Lantmäteriet wich are based on triangulation (also proved a good method in previous studies). The grid created in TerraScan has good properties such as accuracy.
Tillväxt hos Husmossa (Hylocomium splendens) i boreal skog och växthus : effekter av ökad vattentillgång
Hylocomium splendens (Glittering wood-moss) is a common species in the Nordic countries and can be found in many different types of boreal forests. It usually forms dense moss carpets on the forest floor. The shoots grow in segments and new segments form annually on the previous years growth. The size of the segments is probably regulated in a high extent by local micro environmental conditions. Previous experiments suggest increased growth of H.
Fjäderplockning hos värphöns och dess relation till beläggningsgrad i olika inhysningssystem
Majoriteten av alla dödsfall hos värphöns beror på fjäderplockning med efterföljande kannibalism. Fjäderplockningsbeteendet innebär ett mycket stort problem för äggnäringen eftersom det både påverkar fåglarnas välfärd till följd av skador och stress, och dessutom ekonomiska förluster via nedsatt äggproduktion och ökat foderintag. Utsatta fåglar vars fjäderdräkt förstörts kräver mer foder för att bibehålla normal kroppstemperatur. Fjäderplockning är ett multifaktoriellt problem men förekomsten av beteendet har setts öka i takt med den stigande produktionen. Eftersom konsumenternas efterfrågan på billiga ägg ökar tvingas lantbrukarna hålla fler fåglar på samma ytor.
Cultivation of Chlorella vulgaris in nutrient solution from greenhouse tomato production : a possibility to reduce nutrient levels and produce commercially interesting metabolites
The idea of using algae in different areas and exploring its possibilities is nothing new. Already in the early 1950s microalgae was explored as a possible food resource because of its high protein content. Lately there has been an increased interest in its potential for industrial use. Wastewater treatment is a possible use of algae since the algae grow well on the nutrients present in the water. This offers the possibility to grow algae for nutrient reduction and use the biomass for energy or animal feed since many alga species has a good nutritional value.
Approximately 800-1000 m3 water is applied per 1000 m2 of greenhouse area during one season in a tomato production.
Gruppering av sinkor i stora besättningar
The dry period is usually 6-8 weeks and in this period the basis of the performance in the following lactation is settled. In an average herd about 15% of the cows are dry (Marcussen & Krog Laursen, 2008). In many herd the dry cows are set aside, that means setting aside 15% of your herd, at the time when they are preparing for their next lactation. The recommendation for number of groups differs depending on country traditions or reasons for grouping. If you look at recommendation for feeding, some companies selling feeding equipment advocates one group throughout the dry period, but the number differs from one to three.
Utvärdering av liggbåsinredningar för bättre välfärd och hygien hos mjölkkor
The dry period is usually 6-8 weeks and in this period the basis of the performance in the following lactation is settled. In an average herd about 15% of the cows are dry (Marcussen & Krog Laursen, 2008). In many herd the dry cows are set aside, that means setting aside 15% of your herd, at the time when they are preparing for their next lactation. The recommendation for number of groups differs depending on country traditions or reasons for grouping. If you look at recommendation for feeding, some companies selling feeding equipment advocates one group throughout the dry period, but the number differs from one to three.
Hur sker förtätning? : En studie av detaljplaner i Norrköping
Syftet med studien är att bilda kunskap om elevers uppfattningar av och lärares undervisning om särskrivningar. Det görs utifrån frågeställningarna:Hur uppfattar elever särskrivningar?Hur beskriver lärare att de arbetar med särskrivningar i undervisningen?För att besvara syfte och frågeställningar byggdes studien på en kvalitativ undersökning där lärare och elever på två skolor i södra Sverige intervjuades. Intervjuerna genomfördes med fem lärare som undervisar i svenska samt med sju elever i årskurs sex.Datamaterialet analyserades utifrån en fenomenografisk ansats, vilken är den grund studien vilar på. Materialet analyserades och ledde fram till sex kategorier.
Zoonotic Pathogens at the Interface between Humans and Animals in Cambodia, a Rural Approach
A zoonosis is a disease or infection that is naturally transmitted between vertebrate animals and humans. The majority of infectious diseases that affect humans are zoonoses. Environments where wild animals, domestic animals and humans live in close proximity with no or small boundaries in the ecological system favor the transmission of diseases between animals and humans. The above described situation is more common in low income countries, where humans and animals live in high Density and zoonoses are generally more common. The study was conducted in Cambodia.
Förslag till bebyggelse och park i kvarteret Seminariet i Uppsala
In the urban planning debate of today, two strategies for city development stand out as each other's opposites, urban sprawl and smart growth. This thesis concerns a development project of the latter kind and aims to give an alternative proposal to new buildings and a park in a Swedish city block. The term sprawl is used for new developments on virgin soil on the outskirts of cities leading to a city spreading, while smart growth stand for increased city Density through development on re-used land within the city boundaries. The latter are often seen as more sustainable in many levels and are also shown to have positive effects on a number of city functions. At the same time smart growth has negative consequences on other aspects of the city such as public open spaces.