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1814 Uppsatser om Plant selection - Sida 21 av 121
Differences in host plant preferences and olfactory physiology between populations of the moth Spodoptera littoralis established in Egypt and Benin
This study was made to compare and distinguish any differences in olfactory recognition and
host plant adaptation between two strains of cotton leaf worm, Spodoptera littoralis. The
populations used were established in Egypt and Benin, Africa. The documentation consisted of
information about (1) each of the strains development through the larval stage up to pupation on
diets of cotton, clover and cowpea. (2) Their oviposition preferences as adults between cotton,
clover, cowpea, maize and cabbage. (3) Electroantennographic recordings to quantify any
possible responses to plant volatiles.
Throughout the diet experiments the larvae from the Benin strain showed significantly a better
development between artificial, clover, cowpea and cotton respectively, while the Egypt strain
had significance between artificial, cotton and cowpea/clover as diet.
Also noted was how the strains substantial development of weight differentiated if fed the cotton
diet, followed by the cowpea diet showing that the Benin strain would develop a higher body
mass on a cotton diet as well as on a cowpea diet.
This trend was however switched once the pupal stage was reached, where the Egyptian strain
contained a significantly greater body mass than the Benin strain on the artificial and the Benin
strain a greater on cowpea, which suggests that in the end, the Benin strain develops significantly
better on cowpea while the Egypt strain develops better on an artificial diet.
During the oviposition experiment that both stains showed a clear difference in hierarchy of host
plants considered suitable for oviposition, where the Egyptian strain is significantly more
attracted to clover than the Benin strain.
Also showed with electroantennographic recordings and significant values was the higher
sensitivity the Egypt strain had towards (E)2-hexenal, (E/Z)-b-ocimene, (Z)-3-hexenyl acetate,
Nonanal, (-)-linalool and ?-myrcene when compared to the responses from the Benin strain..
Den felande länken : Urval och kvalitetssäkring av Internetlänkar på folkbibliotek
This thesis investigates all aspects of quality and evaluation issues concerning collections of Internet links in public libraries today and in the future. We have studied central theories concerning quality in general as well as quality aspects regarding the Internet and Internet links. In addition to this we have made three case-studies involving the development of collections of Internet links in public libraries of different sizes. The case-studies were made as interviews with professionals responsible for selection, quality assurance and evaluation of electronic information for inclusion in the libraries collections of Internet links. In addition to this we made an e-mail interview with a librarian responsible for one of the most advanced collections of Internet links among Swedish´ public libraries.
Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening
The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.
GROT-transport från norra till södra Sverige
The European Council agreed in 2008 on a climate and energy package to combat global warming. This package is valid for each EU member country and means that greenhouse gas emissions must fall by at least 20% and the EU's energy use to 20%, consisting of Renewable Energy in 2020. The Swedish Government has set stringent climate and energy with the intention to set an example for the rest of Europe. For example, renewable energy sources account for at least 50% of energy use and our climate emissions to fall by 40% by 2020. A combination of these goals and a steadily rising oil price has led to an increased demand for wood fuel in the form of such branches and tops.
Utveckling av en beräkningsmodell för biogasproduktion
A growing interest for the climate and the environment has led to an increased interest forenvironmentally friendly and renewable energy sources, such as biogas. Planning new biogasplants requires a decision basis including facts about approximate amounts of biogas possibleto produce at the plant. The purpose of this thesis is to develop a model that calculates theapproximate biogas and digestate production from a planned or existing biogas plant.Developing the model required a literature review and studies of calculations concerningbiogas and digestate production performed by WSP Sweden AB. As a complement to themodel development, facts about substrates for biogas production were compiled through aliterature review. In addition the methane potential from selected materials was determined bybatch experiments.
Kvalitet i brödvete :
The quality of bread wheat is a large subject to study. The quality rests on two legs. The first one is the inheritance of specific characters, which can be influenced through plant breeding and type of cultivar. The other one is the environmental influences, such as crop rotation, nutrition, harvest and storage. The latter factors are possibly to affect through cultivation practices, while other factors are not possible to influence on for the grower, such as seasonal changes of weather and the soil content.
Integrering av pelletsfabrik med Rya kraftvärmeverk i Göteborg : en teknisk och ekonomisk utredning
Göteborg Energi has a surplus of district heating during spring, summer and fall. The heat surplus is due to a constant production of waste heat from oil refineries and heat from waste incineration over the year. It would be desirable to increase the demand for heat and the uptime for the newly built combined heat and power generation plant, Rya Kraftvärmeverk. One alternative could be to integrate Rya Kraftvärmeverk with a pellet production facility. By producing heat, electricity and pellet in a joint process the energy use can be decreased.
Fosforläckage från växtodling - orsaker och ågärder :
Phosphorus is essential to all plants and is taken up from the soil as the ion H2PO4 - (and to some extent HPO42-). Plant availability depends on, among other factors, the soil pH. In order to provide for plant available phosphorus, it is applied as mineral fertilizers and farmyard manure. However, that causes phosphorus leaching from arable land to surrounding surface waters and lakes and contributes to the eutrofication. There are three types of soils in Sweden that are at higher risk of contributing to phosphorus leakage.
STC-Plant Growth and Development, utvärdering av ett läromedel
Denna uppsats är skriven höstterminen 1997, då ett nytt läromedel började utvärderas i Linköping. Den svenska skolan har sedan en tid haft bristande natur- och teknikundervisning i de lägre årskurserna. Den Kungliga Vetenskapsakademien gav vissa av Linköpings skolor uppdraget att i lärarlag arbeta med ett nytt material, för att kunna se dess fördelar och brister. Materialet heter Science and Technology for Children (STC) och är framtaget av den amerikanska organisationen National Science Resource Center. Sedan utvärderingen av STC har läromedlet bytt namn till NTA (Natur och Teknik för Alla).
Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier
Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in the event of rainfall. An increased level of radioactivity in the plants may occur due to interception and retention of the radionuclides. If the content of the plants is above the threshold limit value, entire yields may have to be destroyed. In order to prevent contamination or decrease the content countermeasures can be taken. The impact of the
biomass, leaf area index (LAI) and growth stage of the plant on the interception and retention is important to know in order to decide which countermeasures to use.
Weather may also be an important factor.
In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley and spring oil-seed rape was studied.
NEDKYLNING HOS VANLIG B?NA, PHASEOLUS VULGARIS
Beans are a global source of plant-based protein, and in some countries, they constitute a primary source of protein intake. With ongoing climate change, including rising temperatures, it is necessary to adapt beans to ensure a reliable food supply. An important mechanism that many plants have, to cope with high temperatures, is cooling through transpiration. During transpiration, stomata open and release water vapor. Water molecules use heat energy from the leaf to convert into gas, thereby cooling the leaf.
Ekonomi i vallfrödominerad växtföljd :
This is a project about how you grow timothy seed and red clover seed successfully. The main part is about economic analyse to see if it is any economy by growing leyseed.
There are lots of things to be aware of to get all the costs in your economic analyze.
Timothy
Timothy seed is planted on 4400 hectares in Sweden. It is possible to grow timothy seed in the south part of Sweden. Timothy is very sensitive for dry weather in spring and in the beginning to summer. Timothy gives acceptable harvest of seed for about three years.
Red clover
Red clover is also sensitive for dry weather and is suitable to grow in the south part of Sweden.
Pain in the ass eller samhällets hjälte- En studie om lekmannaövervakares arbete
The aim of this study is to explore the effects of probation officers and their work. The following questions have been asked to come to a conclusion: How do probation officers view their work and the purpose of it? What are the effects of probation officers work? The approach of the study is of a qualitative nature and has been conducted by interviewing three officers of the correctional service system, three probation officers and two ex-criminals that have been on probation. The selection is based on a snowball type selection. To analyse the results of the study we have applied previous research and phenomenological theory to examine the experience of correctional service officers, probation officers and ex criminals.
Uppfångning och kvarhållning av 134Cs och 85Sr i olika växtutvecklingsstadier
Emissions of radionuclides to the atmosphere can lead to wet deposition on plants in theevent of rainfall. An increased level of radioactivity in the plants may occur due tointerception and retention of the radionuclides. If the content of the plants is above thethreshold limit value, entire yields may have to be destroyed. In order to preventcontamination or decrease the content countermeasures can be taken. The impact of thebiomass, leaf area index (LAI) and growth stage of the plant on the interception andretention is important to know in order to decide which countermeasures to use.Weather may also be an important factor.In this work the interception and retention of 134Cs and 85Sr by spring wheat, ley andspring oil-seed rape was studied.
Boken som aldrig tar slut En undersökning om urval och inköp av kulturtidskrifter på folkbibliotek.
The purpose of this Masters Thesis is to explore the process of selection that librarians face when selecting and acquiring cultural magazines to public libraries. The methods used are qualitative interviews and literary studies. A brief review is given of acquisition policies at public libraries and of cultural magazines and the important role they play in public libraries. Five interviews have been made at five public libraries to find out what factors affect the process of selection when it comes to cultural magazines. Two theories are used as a basis for the analysis of the result of the interviews and literary studies.