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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.
171

Field Methods, Sampling Strategies, Historical Documents, and Data Redundancy: A Study of Historic Tenant Farmsteads in Leflore County, Mississippi

Zoino, Jayson Jon 08 December 2017 (has links)
Historic tenant farmsteads are often thought to be redundant archaeological resources because of their limited temporal range and function which acts to limit the diversity of their archaeological assemblages. However, work has not been done that confirms this equivalence, and archaeologists often write off tenant farmsteads as being too modern or too disturbed to warrant investigation. This is a problematic approach as tenant farmsteads are quickly eroding from the American landscape and a representative sample of sites need to be investigated and preserved before they’re gone. This thesis tests different sampling strategies and field methods that may allow for the efficient investigation of tenant farmsteads without jeopardizing historical knowledge. The results show that the sites studied in this thesis are in fact redundant and a number of different methods can be used to investigate them in a much more efficient manner.
172

IMPACTS OF CLIMATE CHANGE ON THE QUANTITY AND TIMING OF RIVER FLOW IN THE UPPER INDUS BASIN, KARAKORAM-HIMALAYA, PAKISTAN / パキスタン国力ラコルム・ヒマラヤ山脈インダス川上流城における河川流量と流出時期に及ぼす気候変動の影響

BAIG, MUHAMMAD SOHAIB 26 July 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23429号 / 工博第4884号 / 新制||工||1763(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 田中 茂信, 准教授 田中 賢治, 准教授 佐山 敬洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
173

Impacts of Future Climate Change in Water Resources Management at the Chao Phraya River Basin, Thailand / タイ国チャオプラヤ川流域の水資源管理に及ぼす気候変動の影響

Luksanaree, Maneechot 23 September 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22760号 / 工博第4759号 / 新制||工||1744(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 清水 芳久, 教授 田中 宏明, 教授 米田 稔 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
174

Exploring the water-energy nexus in the Omo river basin : A first step toward the development of an integrated hydrological-OSeMOSYS energy model

Sundin, Caroline January 2017 (has links)
The issues of conflicts between water, energy and food (often referred to as WEFnexus) has become a problem in countries where the energy system is rapidly expanding; one of those countries is Ethiopia. Ethiopia has a large potential of hydropower, which is what most of the electricity production currently comes from. However, this has proven to cause problems on other practices around or close to the power plants. An example is the Omo River basin where the development of the Gibe hydropower cascading scheme, with currently the three power plants Gibe I, I and III operating, have brought up the discussion of the downstream impact. For instance, indigenous people living in the lower parts of Omo river, practice flood recession agriculture, meaning they are depending on the seasonal floods. Further, Omo river has its outflow into Lake Turkana, Kenya, and the lake is highly dependent on the flow regime of the Omo river. Studies on the Omo river have been many, an example is the ones using Topkapi-ETH, a physically based rain-fall runoff model, that models the hydrological aspects of the river and considers, among others, water abstraction for irrigation and diversions to reservoirs for hydropower. However, the hydropower modelled worked on the basis of an averaged power demand; not necessarily reflect the actual demand. Hence, OSeMOSYS, the long-term energy optimization tool, was proposed to complement this study by modelling the energy system in Ethiopia. This current thesis had the aim to do so with the attempt to explore the possibility of a coupling between the models Topkapi-ETH and OSeMOSYS. The aim was to feed OSeMOSYS with varying water availability from Topkapi-ETH; in return, OSeMOSYS would feed Topkapi-ETH with a more realistic required energy production demand. An OSeMOSYS model was set up for Ethiopia, with national data extracted from the study The Electricity Model Base for Africa (TEMBA), disaggregating the hydropower to be able to model each of the hydropower plants in the Gibe cascading scheme individually. To couple the two models, two approaches were developed: Storage module and Reservoir module. The Storage module used the storage feature within OSeMOSYS and used the varying volume in the reservoir from Topkapi-ETH and converted it into an energy potential, as input to OSeMOSYS. The Reservoir module, on the other hand, used the external inflow (sum of all flows except upstream release), obtained from Topkapi-ETH, to the reservoir. An experimental set-up was performed to test how the OSeMOSYS model, with the two modules, would react to the input and which inputs were the driving forces affecting the electricity production. The results showed that OSeMOSYS can respond to the varying water availability received from Topkapi-ETH with the electricity production from the Gibe cascading scheme showed results reflecting this. However, there was a mismatch in the hydrological response in which OSeMOSYS did not seem to fully reflect the volume in the reservoir. For certain cases, the volume would be zero, indicating it would not store any water but instead use all incoming water directly for energy production. Hence, with respect to the results presented in this study, one can conclude that OSeMOSYS is prone to respond to changes in water availability. However, due to the incompatibility in the hydrological perspective in regard to the volume, the coupling is not complete. Before such a complete coupling can be achieved one needs to understand why OSeMOSYS does not reflect the hydrological characteristics. If this can be solved, then a feedback of the required energy production in the Gibe hydropower plants ought to be sent back to Topkapi-ETH. / Konflikten mellan vatten, energi och mat (ofta benämnt WEF-nexus) har blivit ett problem i länder där energisystemet snabbt utvecklas; ett av dessa länder är Etiopien. Etiopien har stor potential i vattenkraft, från vilket den största delen av elektriciteten kommer ifrån idag. Däremot har detta visat skapa problem kring andra verksamheter runtomkring eller i närheten av kraftverken. Ett exempel är Omo RIVER BASIN, beläget i sydvästra Etiopien. Exploateringen av Gibe vattenkraftverk i en kaskad schema, idag med de tre kraftverket Gibe I, IO och III i bruk, har skapat diskussion kring påverkan nedströms. Till exempel så bot Urbefolkningen i den nedre delen av Omo floden, där de utövar så kallad flood recession jordbruk, vilket innebär att de är beroende av säsonger av översvämningar för att bevattna marken. Vidare, Omo floden har sitt utflöde in i Lake Turkana, Kenya, och skön är starkt beroende av flödesregimen i Omo floden. Studier kring Omo floden har varit manga, ett exempel är de som har använt sig av Topkapi-ETH, en fysikaliskt baserad nederbörd yt-avrinnings modell, som modellerat de hydrologiska aspekterna I floden och tar hänsyn till, bland annat, extrahering av vatten i bevattningssyfte och diversion till vattenkraftsdam. Dock modellerade vattenkraftverken med utgångspunkt från ett uppskattat energibehov; nödvändigtvis inte det faktiska behovet. Således föreslogs att OSeMOSYS, en LONGTERM energi optimerings modell, skulle komplimentera denna studie genom att modellera energisystemet i Etiopien. Den här uppsatsen hade som avsikt att testa de föregående med en ansats att undersöka möjligheten att sammankoppla de två modellerna Topkapi-ETH and OSeMOSYS. Målet var att förse OSeMOSYS med en varierad vatten tillgänglighet från Topkapi-ETH; i retur skulle OSeMOSYS förse Topkapi-ETH med ett mer realistiskt energiproduktions behov. En modell i OSeMOSYS skapades för Etiopien, med nationella data extraherad från studien The Electricity Model Base for Africa (TEMBA), där vattenkraftverk disaggregerades för att kunna modellera varje kraftverk I Gibe kaskad schema enskilt. För att sammankoppla de två modeller skapades två tillvägagångssätt: Lagrings modul och Reservoar modul. Magasin modulen använde en lagrings funktion i OSeMOSYS med en funktion av den varierande volym i en reservoar från Topkapi-ETH som omvandlades till en potentiell energi. Reservoar modulen däremot använde externt inflöde (summan av alla flöden förutom upströms utflöde), taget från Topkapi-ETH till reservoaren. Ett försök sattes upp för att testa hur OSeMOSYS modellen, med de två modulerna, skulle reagera till indata och vilken indata som är drivande och påverkar produktionen av elektricitet. Resultaten visade att OSeMOSYS kan besvara ett varierade vatten tillgänglighet kommen från Topkapi-ETH där produktionen av elektricitet från Gibe kaskad schema återspeglade detta. Däremot fanns en missanpassning i den hydrologiska responsen där OSeMOSYS inte fullt ut avspeglade volymen i reservoaren. I vissa fall var volymen noll, vilket tyder på att inget vatten kan lagras utan allt inkommande vatten går direkt till turbiner för produktion av energi. Således, med avseende på resultaten presenterade i den här studien, kan en dra slutsatsen att OSeMOSYS kan svara på variationer i vatten tillgängligheten. Däremot, på grund av missanpassning i hydrologiska perspektivet med avseende på volmen, så är inte sammankopplingen mellan modellerna fullständig. Före en sådan fullständig sammankoppling kan uppnås måste en förstår varför OSeMOSYS inte återspeglar denna hydrologiska karaktär. Om detta kan förstås, så kan en feedback av den fordrade energiproduktionen i Gibe vattenkraftverken återsändas tillbaka till Topkapi-ETH.
175

IMPACTS OF CLIMATE CHANGE AND HYDROPOWER DAMS ON FLOW REGIMES AND FLOOD INUNDATION IN THE MEKONG RIVER BASIN / メコン川流域の流況と洪水氾濫に及ぼす気候変動および水力発電ダムの影響

LY, STEVEN 26 September 2022 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第24213号 / 工博第5041号 / 新制||工||1787(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 立川 康人, 教授 角 哲也, 准教授 佐山 敬洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
176

An Ichnological and Sedimentological study of Devonian Black Shales from the Long Rapids Formation, Moose River Basin, Northern Ontario

Bezys, Ruth Krista Angela 07 1900 (has links)
<p>The Long Rapids Formation in the Moose River Basin of northern Ontario is Upper Devonian in age and can be correlated with similar shale deposits in the Michigan, Appalachian, and Illinois Basins . The southern Ontario equivalent to the Long Rapids Formation is the Kettle Point Formation. </p> <p> The Long Rapids Formation is a marine black shale deposited predominantly under depleted oxygen conditions. Large amounts of marine organic matter from the water column and from terrestrial sources accumulated in reducing bottom waters with little recycling to produce brown to black, organic-rich sediments . The depositional basin was stratified, and anoxic bottom waters and oxic surface waters were separated by a pycnocline. The position of the pycnocline (or the absence of it) dictated the type of sediment deposited, and the relative depth of the pycnocline to the sediment-water interface was more important than the absolute depth of the water column. The Moose River Basin in Late Devonian times was located on the Laurasian Continent in an area experiencing tropical conditions and was affected by a period of transgression following the Acadian Orogeny. The black shales in the Long Rapids Formation represent a period of transgression of the large epicontinental Catskill Sea, whereas the green-grey mudstones and carbonates represent periods of minor eustatic changes. </p> <p> Dark-coloured facies with abundant bioturbation are overlain by lighter-coloured facies. Bioturbation is variable in the less abundant green-grey mudstone and carbonate facies, and were also low in organic matter. The ichnofauna suite Chondrites-Planolites-Zoophycos-Alcyonidiopsis-(?Teichichnus) represents an oxygen-minimum ichnofacies found predominantly in dark shale facies. As more oxygen was introduced to the sediment-water interface, more permanent burrow structures were constructed such as Teichichnus, Terebellina, ?Cylindrichnus, Skolithos, and Ichnogenus "A" in the green-grey mudstones and carbonates. As well, body fossils were more commonly found in those facies. The Leiorhynchus brachiopod fauna in the dark-coloured shales probably represents a sparse epifauna living in poorly oxygenated or temporarily oxic conditions in a basinal or open-shelf environment. </p> / Thesis / Master of Science (MSc)
177

Development Of A Fish-Based Index Of Biotic Integrity For Oxbow Lakes Of The Yazoo River Basin, Mississippi

Aycock, Nathan 13 December 2008 (has links)
Fish community data were used to develop an index of biotic integrity (IBI) to quantify habitat degradation in oxbow lakes of the Delta region of the Yazoo River Basin. Daytime boat electrofishing was used to sample the fish assemblage of 30 oxbow lakes during 2006-2007. We evaluated 70 candidate metrics based on their responses to measures of anthropogenic disturbance. Six metrics were retained for inclusion in the IBI: species richness, Shannon’s diversity (H’), average tolerance, and catch rates of buffalo, orangespotted sunfish, and litho-psammophilic spawners. The six IBI metrics showed strong multivariate relationships with measures of habitat degradation in a canonical correlation analysis. Spearman’s rank correlation and scatterplot analysis showed that IBI scores changed in a predictable pattern along gradients of habitat degradation. Three additional lakes were sampled in 2008 and were used to successfully validate the IBI. Biotic integrity was found to be impaired in most oxbow lakes of the Mississippi Delta.
178

Silurian and Ordovician conodont biostratigraphy of the Moose River Basin and Appalachian Basin

Bancroft, Alyssa Marie January 2014 (has links)
No description available.
179

The Role of International River Basin Organizations in Facilitating Science Use in Policy

Wentling, Kelsey 29 October 2019 (has links) (PDF)
Transboundary watershed management seeks to reconcile the dichotomy between political lines and the resources that flow freely over such borders. Transboundary waters cover half of the earth’s surface and define the natural communities of over 40% of the global population. Because water plays an integral role in every culture and society, international entities seek to identify the principles and methods that minimize conflict and maximize harmonious water resource management across borders. Successful management practices to date have aimed to incorporate relevant scientific literature throughout the basin using alternate governance structures. International River Basin Organizations (IRBOs), independent governing structures, provide one such method of governance along shared water bodies. In order to determine how science influences policy and management in IRBOs, this research examines five case studies across three IRBOs: The International Joint Commission, the International Commission for the Protection of the Danube and the Mekong River Commission. To understand the gap between science production and its incorporation into IRBO policies, we conducted a comprehensive literature review and applied the findings from existing scientific literature to understand science-policy process in the five case studies. Within each case study we traced the story of science production and its uptake into policy by highlighting two types of key information in the process: the role of mandates and IRBO structure, and the IRBO’s relationship with relevant actors. Through this process we identified and explored the gap between science production and policy action, demonstrating which mechanisms are essential for generating policy founded on scientific research.
180

Chemical water quality in Selenge River Basin in Mongolia: spatial-temporal patterns and land use influence

Batbayar, Gunsmaa 09 July 2018 (has links)
No description available.

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