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997 Uppsatser om Structural soil - Sida 62 av 67
Monitoring and pest control of Fruit flies in Thailand : new knowledge for integrated pest management
Fruit flies (Tephritidae) are serious pests that cause enormous losses for farmers in many countries. The frequent use of insecticides in controlling fruit flies in fruits and vegetable has not resulted in sustainable management of the pest. Problems associated with this complete reliance on chemical control are many residues of insecticides in crops, health problems for farmers, contamination of water and soil, insecticide resistance development and decrease in natural enemy populations. The implementation of control measures that do not imply an added burden to the environment and/or the farmers is urgent. More knowledge about the ecology of fruit flies is the basis for finding new and better ways to control this pest.
Trädslagsinverkan på markvegetationens utveckling i odlingsförsök med tall och contorta :
In the 1970?s it was predicted that in the beginning of the 21st century there would be a timber shortage in Sweden and a large scale introduction of the exotic tree species lodgepole pine started. An introduction of a foreign tree species means a risk of a negative influence on the forests ecosystem. Today, the stands that were established in the 70?s are middle-aged and the effect on the forest floor vegetation can be studied.
Samtalet på Facebook : En studie om IKEA Sveriges kommunikation i sociala medier
IntroductionIn this study, we have explained the complexities of social media, as it is still a relatively unexplored area. With the rapidly growing use of social media in recent years, companies have chosen to establish themselves in social networks to advertise themselves and communicate with their customers. In this study we analyze IKEA Sweden and their use of social media on the national market, where focus lies upon IKEA Sweden Facebook-page. The study intends to find out how the company uses social media as a marketing and communication tool and also analyzes the relations and conversations that occur on the Facebook-page. Purpose and research questionsThe purpose of the study was to gain a deeper understanding of how a large Swedish company as IKEA has chosen to use social media and how it's perceived by them. We also intended to find out how IKEA Sweden uses social media in their daily work and how the company communicates through this media channel.
Miljö- och kostnadseffekter av att använda höghållfast stål i taket på Swedbank Arena
Examensarbetet är en studie av den fasta delen av takkonstruktionen i Swedbank Arena. Syftet med examensarbetet är att undersöka hur valet av att använda höghållfast stål påverkat kostnader och miljö under hela konstruktionens livstid. I undersökningen har takkonstruktionen dimensionerats med tre olika alternativ där andelen höghållfast stål i konstruktionen har varierats. Nedan beskrivs översiktligt de stålsorter som alternativen är uppbyggda av. - Alternativ A innehåller endast konventionellt stål som har sträckgräns 355 MPa.- Alternativ B är det alternativ som byggts i verkligheten. Den verkliga konstruktionen innehåller stålsorter med sträckgränser mellan 355 MPa - 900 MPa.- Alternativ C innehåller en större andel höghållfast stål än den verkliga konstruktionen.
Den positiva hälsovågen : En kvantitativ studie om hälsofrämjande arbete
The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.
Lantbruksföretagets tillväxtstrategi och finansiella sökbeteende : en empirisk studie av sex lantbruksföretag med tillväxtambitioner
The structural rationalization of the agricultural sector in Sweden has led to many expansive, professional companies orientated towards growth. The agricultural sector is a very capital-intense sector and is characterized by the need for large sums of capital in form of buildings, inventory and arable land. The capital need is especially large for companies who have an ambition of growth and development of the company in the near future.
The study is built upon six cases that all can be categorized as large agricultural farms with a turnover exceeding 20 million Swedish crowns. The companies are located in the middle and in the south of Sweden and are in the sector of primary production with focus on dairy-, pork-, egg-, chicken-, beef-, vegetables- and grain production as well as in the business of refining milk towards consumers.
The study aims to identify the motives and driving forces that lies behind the growth of a farm-based company. The agricultural companies' motive for growth is studied based on which factors that influence the ambition to grow and to what extent these factors accord to the picture given by earlier research of small companies outside the agricultural sector.
Leaf area index in Vittelaria Paradoxa parklands in Burkina Faso estimated by light interception and leaf sampling
Burkina Faso as well as most sub-Saharan African countries struggle with providing food for a fast growing population. The dominating farming system is agroforestry parklands. Agroforestry parklands can broadly be defined as areas where scattered trees occur on farmlands as a result of selective clearing. The presence of trees in crop fields may in the long term have a positive effect on the production of annual crops. It is commonly discussed, but not proven, that the presence of trees leads to increased groundwater recharge due to higher infiltration capacity of the soil.
Fysisk planering ur ett folkhälsoperspektiv ? fallstudie i Hjo
Hur samverkar de nationella folkhälsomålen med fysisk planering, och på vilket
sätt kan folkhälsomålen beaktas för att förbättra förutsättningarna för ökad
fysisk aktivitet hos barn?
Denna studie är en fallstudie i Hjo kommun. Studien tar utgångspunkt i
kommunens folkhälsoproblematik som visar att det finns en hög förekomst av
övervikt hos barn. Intentionen är att undersöka vilka organisatoriska processer
som kan underbygga det kommunala arbetet med folkhälsomålen, liksom att ta reda
på vilka faktorer i den fysiska miljön som skapar förutsättningar för barns
fysiska aktivitet. Avsikten med studien har varit att skapa ett underlag för
Hjo kommuns översiktliga planering.
Konceptarbete om skidbalk i kompositutförande till BVS10
This thesis has been performed at BAE Systems Hägglunds, which is located in Örnsköldsvik. Hägglunds has a wide background of engineering, where they have manufactured all from airplanes to lifting cranes. Currently they only produce track vehicles at Hägglunds, where they manufacture the CV90 and BVS10 models. This thesis concerns the BVS10 which is an all-terrain-vehicle. The main purpose with the BVS10 is to enable transportation of material and personnel thru tough terrain.
Metodik för resistenstest i renkavle : en studie om herbicidresistens; mekanismer, detektion och åtgärder
Herbicide resistance is the result of an evolutionary process where a population gradually changes from being susceptible to being resistant to an herbicide. The resistance mechanism is usually a change in the biochemistry of the weed, but in some cases changes in morphology or growth rhythm. The change is caused by random mutations. Two resistance mechanisms are found in black-grass; target site resistance and metabolic resistance.Black-grass is a tufty, winter annual grass weed, which is mainly found in milder climates. Black-grass is a big problem in Southern Europe.
Vilken effekt har lärkrutor på ogräsfloran vid ekologisk höstveteodling? :
This study forms part of the R&D project "Improved survival of bird chicks in organic fields" managed by the Rural Economy & Agricultural society in Uppsala. The skylark (Alauda arvensis) is a species that has decreased drastically in Sweden as a consequence of more intensive cropping.
Studies in England have shown that skylark reproduction can be greatly improved within
conventional fields, at a low cost, by establishing patches of bare ground (skylark plots).
Within conventional farming, herbicides can be used in case a weed problem arises due to
implementation of these skylark plots, whereas this is not allowed in organic farming. This study examined the effects of skylark plots on the weed culture in organic autumn-sown (winter) cereals and whether weeds might cause long-term problems to farmers.
The study was conducted in two parts; a field study and a review of the literature regarding the weeds observed. The field study was carried out in 2007 during three weeks in June and three weeks in July, on eleven organic fields with winter cereal in the vicinity of Uppsala.
Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna
In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time.
The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.
Byggnation av ett tak i Lwengo Basilla : En fältstudie med fokus på infästningar, pelare och bärläkt på en skola i Demokratiska Republiken Kongo
The Swedish Transport Administration manage nearly 4,000 railway bridges in different condition and age around the country. These bridges is in constant need of maintenance and requires continuous inspections. This thesis is designed as a damage investigation on a single-track railway bridge south of Solvarbo in Säter municipality. The railway bridge is in operation and serves over 10,000 trains a year, everything from speed trains to freight trains. The bridge is built as a beam bridge, simply supported over a road.
Metodutveckling för analys av PBDE och HBCD i sediment
Brominated flame retardants (BFRs) has for many years been used in products to reduce their
flammability, mainly in electronic products, textiles and construction materials.
In 2003, Sweden imported 300 tons of brominated flame retardants.
Leakage of these compounds has polluted natural environments. Fishes has shown increased
contents of these substances, especially fat fish, since brominated flame retardants tends to
accumulate in fatty tissues.
They are also regarded as persistent and that gives them the ability to travel long distances.
What also is really scary is that increased levels of brominated flame retardants have been
detected in human breast milk.
The knowledge of the brominated flame retardants is limited and not so much research has been
done in this field. There are many reasons though, to keep the research going. Partly their
structural resemblance to well-known toxics as PCB, but also their ability to accumulate in
biological systems and enrich in food chains.
In which way they affect humans we really don?t know yet.
Boulognerskogen : förslag till program för en stadslekpark
Boulognerskogen is a park in the central of Skövde that have had a health resort, paths for strolling, outdoor-bath, outdoor-sport areas and events. During the 1970:th there was a lack of interest for the park and very few visited it. By a motion from a resident in Skövde wich proposes that a city playground will be build in Boulognerskogen gave me an opportunity to investigate how the potential of the park can be used to create a funny and nice place to visit for children in company with adults.
By a program that contains the main goals and design program for a city playground in Boulognerskogen, I wanted to present a proposal that could meet childrens needs to play and to use the conditions of the place to create places to play in, and where children in company with adults could be together. To reach this, I wanted to try different methods that could lead to a proposal that was well supported by children and adults, and wich was possible to use by the local authority in their further actions. The methods that I used was therefor an important part of the work.
I have choosen to define the concept "city playground" as a greater playground situated in the center of the town that are suitable for outings and as a meetingplace, with a varation in playground attractions and promote children and adults to be together, aiming at younger children in the ages of 1-10 years in company with adults, but should also give space to activities of other groups.