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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

En fallstudie om implementeringen av hydroponiska stadsodlingar i urbana miljöer

Björn, Johanna, Halldén, Emelie January 2022 (has links)
The purpose of this paper is to investigate, based on a comparative study in Sweden, how vertical hydroponic farms can be implemented in urban environments and to identify the challenges with the implementation. The study examines various companies that work with hydroponic farms in Sweden and how the government can help the companies with the implementation of the innovation. Urban hydroponic farms can be a significant solution for solving the growing global population demand for locally grown fresh food, which includes good quality and nutrients. Previous studies, from a sustainability perspective, show that Sweden would benefit in several different ways if more hydroponic farms were implemented in the urban cities. The theory that the report is based on is the implementation theory. With this in mind, the empirics were analyzed from three different found themes; economy, political priorities & local involvement. Empirical data was collected from previous studies as well as from a qualitative methodological approach. This empirical study was based on multiple interviews with companies in the hydroponic farms industry located in Sweden and observations, to be able to analyze the findings based on our chosen theme. In this study we found that the result indicates that there are both advantages and obstacles to the implementation of hydroponic farms in urban areas. On the other hand, the benefits are predominantly from a sustainable development perspective with new innovative solutions, such as solar systems and upgraded district heating and district cooling systems.
62

Certain Agave Species Exhibit the Capability to be Moderately Productive Under Conditions of High Salt and Drought Stress

Bergsten, Steven J. 13 December 2013 (has links) (PDF)
Water availability and arable lands are increasingly limiting resources in many parts of the U.S., particularly in semi-arid and arid regions. As a means of addressing food and fuel demands associated with burgeoning population growth, highly productive and water-use efficient crops need to be identified. One potential crop, Agave, merits consideration and evaluation due to its putative capability to provide sustenance and energy despite growing in water-limited regions and on marginal soils. However, little is known regarding the productivity these succulent plants will have under growing conditions of the Southwest, where high concentrated saline soils are abundant, and water is often limited. The objectives of these studies were to determine the effects of high levels of salinity and different volumetric water content levels (VWC) on plant growth, biomass accumulation, and nutrient uptake. I used a hydroponic study to compare the effects of four salinity treatments (0.5, 3, 6, and 9 dS m-1) on productivity of four Agave species (Agave parryi, Agave utahensis ssp. kaibabensis, Agave utahensis ssp. utahensis, and Agave weberi). In a second study, an automated irrigation system was established to examine four pre-determined VWC threshold set-points and simulated a gradient of well-watered to drought conditions, to evaluate how A. weberi would respond to varying levels of water availability. Salinity concentrations did not significantly affect root and plant dry weight accumulation in A. weberi, but all other agave plants experienced less biomass accumulation under high saline conditions (>6 dS m-1). Seedlings of A. utahensis were two times more likely to die in the two highest saline treatments (6 and 9 dS m-1) than the two lower treatments (0.5 dS m-1 and 3 dS m-1). Calcium, Mg, S, Mn levels decreased in both A. parryi and A. weberi at higher salinity levels. Agave weberi was able to tolerate salinity, but it also experienced lower biomass production ≤3 dS m-1. In the water-stress study, Agave weberi plants experienced a decrease of 2.11 g as compared to plants in the highest treatment. Plants in the intermediate VWC treatments had similar dry mass values as those in the highest treatment, which suggests that this species could have moderately high yields under limited water conditions, and consequently should be evaluated as a potential bioenergy crop for semi-arid regions, such as the U.S. Southwest. Agave shows considerable potential to be grown in arid and semi-arid regions that are moderately high in salinity and have limited water availability. Indeed, the cultivation of Agave as a crop appears to be a viable option for many areas of the Southwest. While some of the Agave species evaluated were quite productive under moderate salt and water stress, it is uncertain if growth will be significantly reduced if under these stress conditions for periods longer than 3 months.
63

Livscykelanalys av det vertikala odlingssystemet Freja : En fallstudie i samarbete med Swegreen med fokus på att finna miljöpåverkans- hotspots

Brandel, Andrea, Borgström, Nora January 2024 (has links)
Livsmedelsindustrin är en bidragande faktor till klimatförändringarna, där innovativalösningar, såsom vertikal odling, kan appliceras för att främja en hållbar livsmedelsproduktion. Vertikala odlingssystem möjliggör urban inomhusodling,vertikalt i hyllplan, i kontrollerade miljöer med odlingskammare, belysningssystem samt vanligtvis jordfri odlingsmetod (t.ex. hydroponik), som är essentiella delar avsystemet. Temperatur, relativ fuktighet och artificiellt ljus regleras efter grödornas behov. Vid hydroponisk odling används odlingssubstrat såsom stenull istället för jord och växternas rötter är i konstant kontakt med det återcirkulerande vattnet i systemet, som förser växterna med näring. Tidigare livscykelanalyser av vertikala odlingssystem, om än ett begränsat antal, belyser elförbrukningen som den största bidragande faktorn till miljöpåverkan, samt att utbyte av olika material kan generera en lägre total miljöpåverkan. Examensarbetet syftar till att utföra en livscykelanalys på Swegreens vertikala odlingssystemet Freja, på ICA Maxi i Solna. Vidare syftar livscykelanalysen till att identifiera de faser och flöden som står för betydande miljöpåverkan, samt några förbättringsförslag. Det vertikala odlingssystemet antar perspektivet ‘vagga till användning’ under 30 år, exkluderande monterings- och sluthanteringsfasen. Användningsfasen innefattar sallatens livscykel från ‘vagga till grav’, exkluderande förtäringsfasen. Den funktionella enheten är 1 kg producerad ekbladssallat tillgänglig för konsumenter av klass 1. Data har inhämtats från både Swegreens digitaliserade data och från en tidigare studie utförd på Swegreens odlingssystem Saga. För bearbetning har programvaran SimaPro och databasen Ecoinvent 3.8 använts. Resultaten analyseras utifrån miljöpåverkanskategorierna ekotoxicitet (sötvatten), fossil resursanvändning, försurning, klimatförändringar, markanvändning, resursanvändning (mineraler och metaller), vattenanvändning och övergödning (sötvatten). Odlingsfasen för sallaten (innehållande elanvändning) är systemets främsta hotspot, följt av råmaterialsfasen för sallat, som orsakar störst miljöpåverkan för samtliga miljöpåverkanskategorier, förutom för resursanvändning (mineraler och metaller). Resultaten kan ej generaliseras eftersom de beror på val av funktionell enhet, systemgränser samt typ av data. Resultaten från känslighetsanalysen för energiproduktion och sluthantering tyder på att olika scenarion genererar lägst miljöpåverkan, beroende på vilka miljöpåverkanskategorier som anses mest relevanta. / The food industry is a contributing factor to climate change, where innovative solutions, such as vertical farming, can be applied to promote sustainable food production. Vertical farming systems enable urban indoor farming, vertically on shelves, in controlled environments with cultivation chambers, lighting systems and usually soil-free cultivation methods (e.g. hydroponics), that are essential parts of the system. Temperature, relative humidity and artificial light are regulated to satisfy the crops needs. Hydroponic cultivation utilizes growing mediums such as rock wool instead of soil and the roots of the plants are in constant contact with the recirculating water in the system, which provides the plants with nutrients. Previous life cycle assessments of vertical farming systems, although limited in numbers,highlight the electricity consumption as the largest contributing factor to the environmental impact, as well as replacing different materials for a lower environmental impact. This study aims to assess the environmental impacts and hot spots, through the use of life cycle assessment, on Swegreen's vertical farming system Freja, at ICA Maxi Solna. Furthermore the life cycle assessment aims to identify the phases and flows that accounts for significant environmental impact, as well as some suggestions for improvement. The vertical farming system applies the perspective of ‘cradle to use’for 30 years, not including the assembly or waste disposal phase. The use phase includes the life cycle of lettuce, from ‘cradle to grave’, not including the consumption phase. The functional unit is 1 kg of produced oak leaf lettuce, class 1,available to consumers. Data has been obtained from both Swegreen's digitized data and from a previous study conducted on Swegreen's farming system Saga. To process the data, the software SimaPro and the Ecoinvent 3.8 database was applied. Results are analyzed with regards to the environmental impact categories ecotoxicity (freshwater), fossil resource use, acidification, climate change, land use,resource use (minerals and metals), water use and eutrophication (freshwater).Results indicate that the lettuce cultivation phase (containing electricity use) is the main hotspot of the system, followed by the raw material phase for the lettuce. Aphase that also dominates in all environmental impact categories, except for resource use (minerals and metals). Results cannot be generalized since they dependon the choice of functional unit, system boundaries and type of data. The sensitivity analysis regarding the energy production and waste disposal suggests that different alternatives cause the lowest environmental impact, depending on which environmental impact categories are considered the most important.
64

Underhåll av levande väggar : Möjligheter och utmaningar i ett svenskt urbant klimat / Maintenance of living walls : Opportunities and challenges in a Swedish urban climate

Andersson, Johanna, Simu, Malin January 2016 (has links)
Syfte: En långsam utveckling av levande väggar i Sverige beror bland annat på bristande erfarenhet och kunskap inom byggbranschen. Tidigare studier visar bland annat utmaningar gällande teknikens anpassning till ett svenskt klimat och ett krävande underhåll beroende av kompetens, planering och samverkan. Målet med studien är att analysera ett hållbart underhåll utifrån teknik och underhållsplanering av systemet levande väggar för att kunna besvara dessa problem. Metod: Studien är av kvalitativ karaktär där använda metoder är dokumentanalys, intervju och observation. Dokumentanalys ger en lägesbild av implementerade lösningar i södra Sverige och strategier för underhållsplanering. Intervju med relevanta aktörer bidrar med erfarenheter om teknik, underhåll och planering. Observation bekräftar information om teknik. Resultat: Studien visar på att ingen av de studerade konstruktionslösningarna kan anses fullständigt hållbara, men det finns systemlösningar som har mer eller mindre hållbara egenskaper. Levande väggar har starka sociala och ekologiska fördelar, där växtligheten bidrar till att öka ekosystemtjänsterna i urban miljö. En mindre resursanvändning är nödvändig för en hållbar teknik, där naturlig bevattning, lokala tåliga växter, varaktig konstruktion samt återvunna materialkomponenter främjar hållbar miljö och ekonomi. Filtdukssystem är enklare i design medan modulsystem är mer flexibelt. Ett gemensamt mål bland studerade projekt är att skapa ett så underhållsfritt system som möjligt där väggen får leva på naturlig väg. Acceptans för vilande växter under vinterhalvåret kan sänka krav på underhållet. Teknisk övervakning underlättar men manuell tillsyn är vital för väggens överlevnad. Frekvensen på underhållet varierar från projekt till projekt där kundens önskemål, placering, typ av vägg, storlek, växtval och årstid påverkar. Därför är det viktigt med planering och kontinuerlig utvärdering av behov. Majoriteten av studerade projekt har ingen tydlig underhållplanering, men studien visar på framgångar av ett tydligt gemensamt mål, tidig involvering av driftpersonal, platsanalys, målinriktad underhållsplan och erfarenhetsåterkoppling. Konsekvenser: Studiens slutsats är att tekniken för levande väggar behöver utvecklas för att för att lämna ett mindre fotavtryck på miljö och ekonomi. Utvecklingen går mot ett så underhållsfritt system som möjligt, men den manuella tillsynen kan inte ersättas helt av avancerad teknik. Varje anläggnings unika förutsättningar kräver noggrann planering och kontinuerlig utvärdering av behov. Begränsningar: Studien behandlar levande väggar i ett svenskt urbant klimat, där resultatet baseras på erfarenheter från projekt utförda i södra Sverige. Annan geografisk placering skapar andra förutsättningar för teknik och underhåll. Mer generella antaganden kan göras gällande underhållsplanering. Fler intervjuer med underhållstekniker kan bidra med andra aspekter i analysen. / Purpose: A slow development of living walls in Sweden is partly due to lack of experience and knowledge in the construction industry. Former studies point at challenges of adapting the technique in a Swedish climate and the importance of planning, knowledge and cooperation for the maintenance. The objective of the study is to analyse a sustainable maintenance by technique and maintenance planning of the system living walls in order to answer these challenges.   Method: The study is based on a qualitative approach where the methods are document analysis, interview and observation. Document analysis gives a status report of the implemented living walls in Sweden and introduces strategies for maintenance planning. Interview with relevant participants contributes with experiences concerning technique, maintenance and maintenance planning. Observation confirms the information about the technique. Findings: The study shows that none of the observed solutions can be considered completely sustainable, though they do have some sustainable qualities. Living walls have strong social and ecological benefits, where the vegetation contributes to increase ecosystem services in urban environment. A less use of resources is necessary for a sustainable technique where the use of stormwater, local resistant plants, lasting construction and recycled components promotes a sustainable environment and economy. The felt system is simpler in its design while the modular system is more flexible. A common objective among the observed projects is to create a maintenance-free solution as possible. Acceptance for resting plants during winter can lower the demands of the maintenance. Technical monitoring facilitates the maintenance but the manual handling of living walls is crucial. The frequency of the maintenance varies from each project where the client’s choice, placement of the wall, type of solution, size, plant choice and season affect. Therefore, it is important with planning and constantly evaluating a walls needs. The majority of the observed projects do not have a maintenance plan but the study shows success by a common objective, site analysis, goal-oriented maintenance plan and experience feedback. Implications: The conclusion of the study is that the technique of living walls needs to be evolved to leave a smaller footprint on the environment and the economy. The development is towards a maintenance-free solution but the manual handling can not be replaced by advanced technique. Every projects individual conditions demands thorough planning and continuous evaluation of the wall. Limitations: The study discuss living walls in the Swedish urban climate, where the result is based on experiences from projects developed in the southern part of Sweden. Other geographical placement causes different conditions for technique and maintenance. General assumptions can be made concerning the maintenance planning. More interviews with maintenance staff can contribute with other aspects to the analysis.
65

Growth, yield and quality of hydroponically grown tomatoes as affected by different particle sizes of sawdust

Maatjie, Maboloke Abram 23 March 2016 (has links)
The tomato is one of the most important vegetable crops grown in the South African community. Most hydroponic tomato growers in South Africa are using sawdust as a growing medium due to its availability and affordability. However, there is little or no information on how particle sizes of sawdust influence tomato yield and quality. The aim of the study was to determine the effect of the particle size of sawdust on plant growth, yield and quality of tomato. Six treatments of different particle sizes of sawdust i.e. fine (F), medium (M), coarse (C) and 50:50 ratio of F: M, C: M, and C: F extracted from pine tree were used for the experiment. Treatments were arranged in a randomized complete block design with four replicates. The size of the sawdust particles did not have a significant effect on plant height, stem diameter, leaf length and width, shelf-life, marketable yield, total yield and unmarketable yield. A tendency to increase marketable and total yield was observed when tomato plants were grown at a 50:50 C: F ratio. Fruit and leaf mineral content were not affected by sawdust particle size. After completion of the experiment, air- filled porosity was significantly high on particle size C, M, and C: M while the water holding capacity was significantly high on F followed by M. The study showed that the suitable growth medium for production of tomatoes under the hydroponics system used was the CF particle substrate. Generally, the experimental crop performed better under the CF particle substrate in terms of growth parameters, and fruit quality, thus leading to the conclusion that the CF growth medium is ideal for hydroponically grown tomato under a non-environmentally controlled polytunne / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)
66

Growth, yield and quality of hydroponically grown tomatoes as affected by different particle sizes of sawdust

Maatjie, Maboloke Abram 23 March 2016 (has links)
The tomato is one of the most important vegetable crops grown in the South African community. Most hydroponic tomato growers in South Africa are using sawdust as a growing medium due to its availability and affordability. However, there is little or no information on how particle sizes of sawdust influence tomato yield and quality. The aim of the study was to determine the effect of the particle size of sawdust on plant growth, yield and quality of tomato. Six treatments of different particle sizes of sawdust i.e. fine (F), medium (M), coarse (C) and 50:50 ratio of F: M, C: M, and C: F extracted from pine tree were used for the experiment. Treatments were arranged in a randomized complete block design with four replicates. The size of the sawdust particles did not have a significant effect on plant height, stem diameter, leaf length and width, shelf-life, marketable yield, total yield and unmarketable yield. A tendency to increase marketable and total yield was observed when tomato plants were grown at a 50:50 C: F ratio. Fruit and leaf mineral content were not affected by sawdust particle size. After completion of the experiment, air- filled porosity was significantly high on particle size C, M, and C: M while the water holding capacity was significantly high on F followed by M. The study showed that the suitable growth medium for production of tomatoes under the hydroponics system used was the CF particle substrate. Generally, the experimental crop performed better under the CF particle substrate in terms of growth parameters, and fruit quality, thus leading to the conclusion that the CF growth medium is ideal for hydroponically grown tomato under a non-environmentally controlled polytunne / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)
67

Automatizované pěstování rostlin / Automated Plant Growing

Švancer, Jan January 2017 (has links)
This thesis combines two current trends - the Internet of Things and Urban Agriculture. It describes technologies for wireless sensors communication in smart homes and hardware for their implementation. Based on these technologies smart hardware for automatic plants growing is implemented and connected to cloud with remote access via iOS mobile application.
68

Chráněné bydlení na Kociánce. Bydlení ve městě - městská necentra a proměny periferie / Sheltered housing at Kociánka in Brno

Ondruch, Matěj Unknown Date (has links)
The diploma thesis deals with the topic of sheltered housing solutions for people with special needs on the southern edge of the Kociánka complex in Brno. The aim of the work is not only the design of sheltered housing, but also the creation of opportunities for social integration and clients interaction with the public and at the same time the creation of job opportunities, space for recreation, therapy, self-realization or activation. The main element is the interweaving that is reflected in the entire design, whether it is urbanism, architecture or technology.
69

Effects of Low Nutrient Solution pH on Hydroponic Leafy Green Plant Growth, NutrientConcentration of Leaf Tissue, and Pythium Zoospore Infection

Gillespie, Daniel Patrick January 2019 (has links)
No description available.
70

Transitioning towards Sustainable Agriculture in the European Union through Change Management and Transformational Leadership

García Sánchez, Miguel, Warnshuis, Maarten January 2021 (has links)
This paper examined how Change Management and Transformational Leadership can be effective tools in transitioning towards sustainable agriculture in Europe. This paper starts with providing empirical evidence for climate change and shows that Northern and Southern Europe are impacted differently by climate change. Then this paper examined how climate change affects farmers in the different parts of Europe and what Societal, Environmental, Leadership and Organisational changes have to be made to transition towards sustainable agriculture in Europe. The qualitative analysis shows that, according to farmer associations, there is a need for a variety of options, a lack of communication and insufficient involvement of farmers on a policy making level. This paper ends with explaining how Change Management and Transformational Leadership can be used as tools to improve communication between stakeholders and improve the involvement of farmers in the co-creation process. Therefore, this paper concludes that Change Management and Transformational leadership will help the European Union in realising sustainable agriculture in Europe.

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