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2514 Uppsatser om The greenhouse effect - Sida 1 av 168

Datormodellering av en värmelagrande betongväggs inverkan på det termiska klimatet i ett växthus

This report describes the building of a computer model that makes it possible to simulate the thermal climate in a greenhouse. The computer model is built on the physical theory of heat exchange that occur in a greenhouse, such as radiation and convective heat exchange. The model also includes the heat storage that is active in a greenhouse.The computer model is used to simulate the thermal climate in a greenhouse under three periods, winter, spring and summer. It also investigates which effect a concrete wall has on the thermal climate in a greenhouse. The purpose of putting a concrete wall in the greenhouse model is to investigate the possibility to store heat during the day and then use this heat when the temperature drops during the night.The result from the simulations shows that a concrete wall levels the big difference in temperature that normally occurs under a day in a greenhouse.

En renässans för kallväxthuset :

The unheated greenhouse was originally a development from orangeries in the 1700th century and in 1930 and 1940 in blocks of greenhouses in the province of Scania. Today unheated greenhouses are used in permaculture, in the?eco villages? and in commercial culturing. Of the total Swedish commercial greenhouse area is today 8 % used as unheated greenhouses (SJV). This essay is based on the acceptance that unheated greenhouses will have a renaissance as production units. In the light of the today?s debate about energy ? and environment and the condition concerning this, the unheated greenhouse becomes an alternative. The purpose of this essay is to make an arguing synopsis about unheated greenhouses for using in acting as teacher, consultant and inspirer and also for taking part of the acceptance as ?for? or ?against?. The information is based on literature studies and information gathered with the keywords unheated greenhouse, coolhouse, coldhouse, greenhouse, type of greenhouse, orangery, greenhouse cultur, swedish greenhouse culture and permaculture, data gathering through SCB/SJV and by interviews with persons in the garden branch. My conclusion is that the unheated greenhouse could have a renaissance as a production unit. In this context it is important to give cultivators of greenhouses with experiences of unheated greenhouses great possibilities to share their knowledge, and through education possibility to change attitudes concerning unheated greenhouses. .

Biological control of powdery mildew in greenhouse produced cucumber : an evaluation of two microbiological control agents

Powdery mildew is a serious problem in both field and greenhouse cucumber production and can cause serious infection and radically reduced yields. Today, powdery mildew is the main disease in greenhouse produced cucumber. Disease control should preferably be both efficient and environmentally friendly, which is not easy to achieve at all times. Alternatives to chemical control of powdery mildews are biological control, physical control, non-fungicide control and cultivation of resistant or tolerant varieties. Biological control can be described as the suppression of damaging activities inflicted of a harmful organism by one or more other organisms, which are called antagonists or natural enemies. In Sweden, there are currently no registered biological control products available to control cucumber powdery mildew. The aim of this study was to investigate the effect of two biological control products in order to evaluate their ability to prevent or reduce powdery mildew infection to an acceptable level in greenhouse produced cucumber. In the experiments, different application regimes were also studied.

Elevers syn på klimatfrågan : Klimatundervsiningen i skolan

The aim of this study is to find out in which way the education about climate in school is taught and how the students experience the world situation today. There are various theories about The greenhouse effect and its origin and these theories should be addressed to ensure that students get a broader understanding of how climate change occurs. This includes the natural phenomena and also the human impact on climate change. Students in school are a source of concern that only human are the cause of global warming, and know little or almost nothing about the natural phenomena of global warming.  I will mention what has emphasized in the national steering documents in the case of environmental education at school.I have used a qualitative method, where interviews and document analysis were used as techniques. The interviews took place with five students in ninth grade and with three science teachers in the same school..

En analys av nattliga koldioxidflöden i en boreal barrskog avseende spatial och temporal variation

Carbon dioxide in the atmosphere contributes to The greenhouse effect, which is essential tolife on our planet. Furthermore, it plays an important part of the photosynthesis andrespiration of the world?s organisms. Since the start of the industrial revolution the amount ofcarbon dioxide in the atmosphere has increased exponentially. The main source is theextensive burning of fossil fuels.

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.

Följdeffekter av olika användningssätt för vedråvara : en ekonomisk studie

Since the turn of the millennium a sharp increase in the interest for bio energy has been observed. Important reasons for this growing interest can be due to the fact that fossil fuels are a finite resource. A net discharge of greenhouse gases occur when fossil fuels are burned. The discharge of greenhouse gases are considered to be the main reason to The greenhouse effect. Means of control to increase the use of bio energy has been introduced and, as intended, the use of bio energy has increased. As a result of the legal provisions the ability to pay for bio energy has increased, which the forest industry view as a problem.

Effekten av metyljasmonat som skydd mot gnag av snytbagge (Hylobius abietis) på gran- och tallplantor :

The effect of methyl jasmonate on resistance against the large pine weevil (Hylobius abietis) in Scots pine and Norway spruce seedlings. A field experiment was conducted in order to determine the dose-response effects of methyl jasmonate (MJ) on growth and defence to pine weevils in Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) and to compare the effect of MJ between pine and spruce. In addition a complementary greenhouse experiment was conducted with the same aims as above and to determine the amount of resin ducts and their correlation to the feeding of pine weevils. The field experiment was conducted on a fresh clear cutting in Garpenberg, southern Dalarna in central Sweden. The experiment consisted of 30 blocks with three kinds of containerized seedlings: 2-year old spruce, small pine (before shoot elongation) and 1-year old pine (already shoot elongated). They were all exposed to 4 treatments 14 days prior to the experiment: control, 25 mM/L MJ, 50 mM/L MJ and 100 mM/L MJ. Data on weevil damage and seedling growth were collected after the first and the second growing season. The seedlings in the greenhouse experiment were of the same kind and were exposed to the same treatment as the ones in the field experiment.

Societetsparken i Norrtälje : nulägesanalys och utvecklingsförslag

The short term effect of phosphorus in sewage sludge was investigated to establish howmuch of this a farmer can grant him- or herself, if using sewage sludge as a phosphorusfertilizer. Possible differences in plant availability between sludge phosphorus precipitatedby iron, aluminum or calcium integrations were studied in a sandy soil at two pH levels.The sludges were analyzed using pot and incubation trials. As the intention was to investigategrowth limitation due to phosphorus deficiency, a soil with low phosphorus supplywas chosen as well as a low phosphorus application rate. Sludge corresponding to 12kg phosphorus per hectare was applied. Treatments fertilized by sludge were compared totreatments where 0, 6 and 12 kg phosphorus per hectare from mineral fertilizer was applied.Every treatment was replicated six times.

Kortsiktig fosforeffekt av avloppsslam : krukförsök i växthus där järn-, aluminium- respektive kalkfällt slam använts som fosforgödselmedel

The short term effect of phosphorus in sewage sludge was investigated to establish howmuch of this a farmer can grant him- or herself, if using sewage sludge as a phosphorusfertilizer. Possible differences in plant availability between sludge phosphorus precipitatedby iron, aluminum or calcium integrations were studied in a sandy soil at two pH levels.The sludges were analyzed using pot and incubation trials. As the intention was to investigategrowth limitation due to phosphorus deficiency, a soil with low phosphorus supplywas chosen as well as a low phosphorus application rate. Sludge corresponding to 12kg phosphorus per hectare was applied. Treatments fertilized by sludge were compared totreatments where 0, 6 and 12 kg phosphorus per hectare from mineral fertilizer was applied.Every treatment was replicated six times.

Frysa livsmedelsrester eller kassera dem för biogasproduktion : En studie, ur livscykelperspektiv, av energianvändning och växthusgasutsläpp

Food is widely consumed and in 2011 an average American devoured approximately one ton of food. The production of these goods requires large amounts of energy and contributes to 22-31 % of all greenhouse gas emissions occurring in Europe. More than one third of the produced food is discarded instead of consumed, and food waste make up about 30 % of the waste generated by households. 60 % of this food waste could be avoided if the eatables were handled in a better way.Avoidable food waste arises partly because residues from food are not taken care of, and because the food is not stored in a way that optimise its durability. Residues arises part- ly because of the contradictory and complex demands of everyday life and are, because of our busy lifestyle, difficult to avoid.

Förannonsering och medieval och dess påverkan på attityder, third person effect och investeringsattityden

This bachelor thesis explores earlier findings regarding the Nextopia effect and the choice of media for advertising, and how these phenomena influence consumer attitudes toward the ad itself as well as the brand. It also explores the effect of advertising future products and advertising in two different media on the third person effect. Lastly, it addresses the effect of advertising of future products and media choice on the attitude of potential investors..

Biological control of Fusarium wilt on tomatoes : use of Bacillus subtilis and interactions with the earthworm Pontoscolex corethrurus in a Kenyan highland soil

It is important to investigate the potential of biological control measures in agricul-ture, especially where economic issues restrict the use of expensive inputs or when there are environmental concerns about toxicity of agrochemicals. The bacterium Bacillus subtilis has proved promising as a biocontrol agent (BCA) in suppressing various plant diseases and it has also been shown to promote plant growth in certain cases. During this study, the effect of B. subtilis on Fusarium wilt (caused by the fungus Fusarium oxysporum) on tomatoes, as well as its effect on the earthworm species Pontoscolex corethrurus was investigated. Furthermore, the combined ef-fect of the BCA with P.

Handel med utsläppsrätter inom EU - Möjlighet eller papperstiger

This study in Environmental Science examines the amendment of the EU-Directive on. Greenhouse gas emission allowance trading. The Directive is to be considered as a tool for fulfilling the obligations that the Union and its member countries have taken on through the 1997 Kyoto agreement together with the protocols proposed at that time. The flexible mechanisms of the protocol are intended as instruments for limiting the climatic changes arising from anthropogenic sources, emission allowance trading being one of these mechanisms. The results presented here consist primarily of an analysis of interviews with various experts in the field of emission control concerning the possibilities and problems attending the process of implementation.

Underlag till klimatledningssystem för skolor

The climate issue is a significant question, and the problem is mainly caused by human activities. Everyone can help to counteract the enhanced Greenhouse effect by reducing the amounts of energy they use and by not consuming more products then they need.Schools are some of societies many consumers and therefore contribute to The greenhouse effect. The School also has an important task; to teach and disseminate knowledge and information about the climate and the environment. According to the Swedish National Agency for Education, Skolverket, must all schools regularly consider the environment and sustainable development throughout the entire education process. Unfortunately, this is not the case for many schools in Sweden today.One of many tools that can be used to coordinate environmental work and initiatives, and also to make it more efficient, is environmental management systems.

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