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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.
31

Use and Abuse of Southwestern Rivers: The Pueblo Dweller

DiPeso, Charles C. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / In response to the 20th century crisis of environmental destruction by unrestricted technological exploitation, some archaeologists are studying alternative modes of resource development as practiced by earlier men. The pueblo Indians of the arid southwestern deserts were basically upland corn farmers, who, after A.D. 1000, found it necessary to exploit their environment because of varying combinations of climatic change and increased population pressures. In the northeastern part of the state of Chihuahua, urban engineers, ca 1050, harnessed the entire Casas Grandes dendritic pattern by installing a set of linked hydraulic appointments which included various upslope protective devices such as linear border, check dams and riverside and hillside terraces. Not only were they able to visualize an entire dendritic pattern as the target area, but also they were able to conceive of rainfall and topsoil as a single factor in their control designs. Although large amounts of human labor were needed to construct and maintain these systems, few raw materials were needed. When the mountain-born waters reached the lower valleys, they were clear and sluggish, did not flood the bottomlands, and because of the reduced speed, could easily be diverted into canals and reservoirs, supplying the cities with domestic water and the farmers with irrigation water. Many further studies are needed of these pre-Columbian systems.
32

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.
33

Effluent Water Quality Improvement Using Silt Fences And Stormwater Harvesting

Gogo-Abite, Ikiensinma 01 January 2012 (has links)
Construction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and other impervious surfaces are routinely discharged into ponds for treatment before being released into a receiving water body. Stormwater harvesting from a pond for irrigation of adjacent lands is promoted as one approach to reducing pond discharge while supplementing valuable potable water used for irrigation. The reduction of pond discharge reduces the mass of pollutants in the discharge. In the dissertation, presented is the investigation of the effectiveness of temporary sediment barriers and then, development of a modeling approach to a stormwater harvesting pond to provide a comprehensive stormwater management pollution reduction assessment tool. The first part of the research presents the investigation of the performance efficiencies of silt fence fabrics in turbidity and sediment concentration removal, and the determination of flowthrough-rate on simulated construction sites in real time. Two silt fence fabrics, (1) woven and the other (2) nonwoven were subjected to material index property tests and a series of field-scale tests with different rainfall intensities and events for different embankment slopes on a tilting test-bed. Collected influent and effluent samples were analyzed for sediment concentration and turbidity, and the flow-through-rate for each fabric was evaluated. Test results revealed that the woven and nonwoven silt fence achieved 11 and 56 percent average turbidity reduction iv efficiency, respectively. Each fabric also achieved 20 and 56 percent average sediment concentration removal efficiency, respectively. Fabric flow-through-rates were functions of the rainfall intensity and embankment slope. The nonwoven fabric exhibited higher flow-throughrates than the woven fabric in both field-scale and laboratory tests. In the second part of the study, a Stormwater Harvesting and Assessment for Reduction of Pollution (SHARP) model was developed to predict operation of wet pond used for stormwater harvesting. The model integrates the interaction of surface water and groundwater in a catchment area. The SHARP model was calibrated and validated with actual pond water elevation data from a stormwater pond at Miramar Lakes, Miramar, Florida. Model evaluation showed adequate prediction of pond water elevation with root mean square error between 0.07 and 0.12 m; mean absolute error was between 0.018 and 0.07 m; and relative index of agreement was between 0.74 and 0.98 for both calibration and validation periods. The SHARP model is capable of assessing harvesting safe-yield and discharge from a pond, including the prediction of the percentage of runoff into a harvesting pond that is not discharged. The combination of silt fence and/or polyacrylamide PAM before stormwater harvesting pond in a treatment train for the reduction of pollutants from construction sites has the potential of significantly exceeding a performance standard of 85 percent reduction typically required by local authorities. In fact, the stringent requirement of equaling pre- and post-development pollutant loading is highly achievable by the treatment train approach. The significant contribution from the integration of the SHARP model to the treatment train is that real-time assessment of pollutant loading reduction by volume can be planned and controlled to achieve target performance standards.
34

Återvunnet avloppsvatten, dagvatten eller dricksvatten för bevattning? : En multikriterieanalys över alternativa vattenkällor för bevattning hos Malmö Burlöv Golfklubb / Recycled waste water, stormwater or drinking water for irrigation? : A multi criteria analysis of alternative irrigation sources at Malmö Burlöv Golf club

Värnqvist, Sara January 2021 (has links)
Förändrade förhållanden följer de allt mer påtagliga klimatförändringarna. Stora delar av samhällen är beroende av tillgång på rent vatten vilket tvingar länder till klimatanpassning. I Sverige lider många regioner av vattenbrist medan andra har tillgång en större mängd vatten. I, bland andra, Skåne väntas stora temperaturhöjningar vilket medför mer avdunstning och torrare förutsättningar. Klimatförändringarna förväntas öka trycket samhället ställer på de tillgängliga vattenresurserna. Malmö Burlöv Golfklubb (Malmö Burlöv Gk) belägen i västra Skåne är en av många som kommer påverkas av de torrare förutsättningar samt ökade mängder av näringsämnen som göder vattendragen. Deras nuvarande vattenkälla för bevattning, Sege å, saknar tillfredsställande vattenkvalitet och därmed söker golfklubben efter andra alternativ.  Syftet med examensarbetet är att identifiera och jämföra lämpligheten för tre alternativa vattenkällor för bevattning av golfbanan hos Malmö Burlöv Golfklubb jämfört en referens. Lämpligheten att användas som källa för bevattning utreds genom multikriterieanalys (MKA), med verktyget Water Investments for Sustainability Enhancement and Reliability (WISER). Via extern litteratur identifierades tre alternativa bevattningssystem samt ett referenssystem. Systemen vilka inkluderades i analysen var återvunnet avloppsvatten, dagvatten, dricksvatten samt bevattning med grundvatten (referens). Litteraturen över tidigare forskning visar att systemen används runt om i världen med olika framgång. I länder såsom Australien, USA och delar av mellanöstern används återvunnet avloppsvatten för bevattning av vindruvor vilket avlastar samhällets vattenresurser. I Indien har höga koncentrationer av olika skadliga ämnen uppmätts i områden där avloppsvatten, vilket endast genomgått en enkel reningsprocess alternativt ingen rening, används för bevattning. Studien betonar vikten av avancerad rening av det inkommande vattnet innan det används.  Ett flertal studier visar att en alternativ bevattning (icke-dricksvatten) ofta anses mer acceptabelt bland allmänheten. I en del av Kanadas parkområden används dagvatten för bevattning vilket visat ha en positiv effekt på människors uppfattning kring användande av alternativa vattenkällor. Studier visar även att användarna kräver en viss distans mellan vatten, från den alternativa vattenkällan, och individ. Alternativa system har därför implementerats för ändamål där exponeringen är låg, till exempel vid bevattning, vilket har visats vara gynnsamt.  I examensarbetet jämfördes de tre identifierade alternativen med referenssystemet utifrån 22 kriterier vilka inkluderar teknisk, social, ekonomisk samt miljömässig analys. Samtliga kriterier inkluderade i analysen är presenterade av verktyget WISER. Utifrån tidigare studier, rapporter samt antaganden gjordes en bedömning av alternativens prestation för varje enskilt kriterium. Resultatet som erhölls, via viktning som genomförts av kund- och marknadsansvarig på Malmö Burlöv Gk, visar att systemet som brukar dagvatten för bevattning kan anses mest lämpligt utifrån förutsättningarna för den studerade golfklubben. Systemet är det enda som erhåller ett positivt slutligt index och erhåller endast lägsta poäng för två av 22 kriterier medan det erhåller poäng vilken indikerar en likgiltig, tillfredsställande samt mycket tillfredsställande prestation för 19 av 22 kriterier. Utifrån resultatet ges därför rekommendationen att dagvatten för bevattning är det mest lämpliga alternativet för Malmö Burlöv Gk men att justeringar av systemet behöver genomföras innan implementering.  Känslighetsanalysen visar dock att resultatet begränsas av golfklubbens ekonomiska tillgångar vilket innebär att systemet som brukar återvunnet avloppsvatten kan rekommenderas för implementering om golfklubben kan beviljas bidrag. Övriga system kan inte uteslutas vara lämpliga alternativ då en MKA och WISER endast ger en indikation vilket system som är att föredra relativt de andra alternativen och inte hur alternativen presterar jämfört riktlinjer, standarder och regler. / Climate change has become a world known phenomenon. Parts of societies are dependent on the availability of clean water which puts a greater pressure on nations to adapt to the changing climate. Many regions in Sweden, Scania amongst others, is affected by water scarcity and therefore, societies are predicted to put a greater pressure on water sources used throughout the communities. A golf course located in western part of Scania, Malmö Burlöv Golf club (Malmö Burlöv Gk), will be one of many that will be impacted by the droughts and the increase of fertilizers in watercourses. Their current water source, the water course Sege å, used for irrigation has an inadequate water quality which has caused Malmö Burlöv Gk to seek other options.  The aim of the master thesis is therefore to identify and compare the suitability for irrigation purpose of three alternative water sources at Malmö Burlöv Gk. The comparison was made in Water Investments for Sustainability Enhancement and Reliability (WISER) which is a new multi-criteria analysis (MCA) tool. Three alternatives were identified by reading literature and previous studies. The three systems included in the analysis were recycled wastewater from Sjölunda wastewater treatment plant, stormwater and drinking water. Previous studies indicated that similar systems, for example recycled wastewater, were used in many different parts of the world, with different levels of success. In Australia, the US, and parts of the middle east the use of wastewater for irrigation of grapes allowed clean water to be reallocated for other purposes. However, in India, where untreated wastewater was most used high concentrations of harmful substances could be found in the crops and ground where the water was used.  In the master thesis the three alternatives were compared to a reference system, irrigation with groundwater, based on 22 criteria which were chosen from WISER. The criteria were based on social, technical, environmental, and economic aspects. Each criterion received a grading based on the performance of the alternative, which was based on previous studies, reports, and assumptions. The results show that the stormwater system is the most suitable based on the conditions at the site as it obtains a positive score (or neutral) for 19 of the 22 analyzed criteria. In addition, the sensitivity analysis show that the results are heavily dependent on the golf clubs’ economical assets. Therefore, a recommendation to implement stormwater system with a few adjustments or, if grants can be found, the system for recycled wastewater is made.  Furthermore, the choice of methodology (MCA) will have an impact on the results where for example, scoring will affect the relative grading. In addition, an MCA and WISER can only decide which alternative will be considered more suitable compared to the rest of the alternatives and not if it is applicable at the site. The performance of the alternatives relative existing guidelines and laws must be investigated before implementing the chosen system. It is therefore important to recognize the rest of the alternatives as suitable before proven otherwise.
35

Use and Abuse of Southwestern Rivers: The Desert Farmer

Ayres, J. E. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / The pre-Columbian Hohokam Indians occupied the major river drainages of central Arizona, and have been the subject of much intense archaeological research. Evidence indicates that the Hohokam began using river water for crop irrigation about 300 B.C., and modified and improved their irrigation systems over time, until the maximum extent of these systems was achieved about 900 a. D. Two types of water control seem to have been utilized: (1) the direct exploitation of rivers through the use of irrigation canals, (2) indirect use through controlled runoff within microdrainages at higher elevations before it reached the rivers. At first, probably only those parcels of land with optimal soils and drainage were used, but apparently population increases fostered by agriculture itself, combined with increasing social and political complexity, necessitated more and more exploitation of marginal lands. Eventually soil problems increased, imposing severe limitations on agriculture. These involved salt and alkali accumulation due to inadequate drainage, soil density and water logging. Additionally, the extension of cropping required the clearing of natural vegetation, which resulted in increased erosion and decreased available native food resources for periods when crops failed. The culture vanished completely about 1450 a. D., probably mainly because of their manner of river exploitation for irrigation. More recent archaeological studies are concentrating not only on river use but also on river abuse.

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