Дисертації з теми "Lot (river)"
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Javonena, Anne-Charlotte. "Châteaux et domaines castraux, outils de contrôle des réseaux de communication au Moyen Âge : l'exemple de la vallée du Lot (XIIIe -XVe siècles)." Electronic Thesis or Diss., Université Clermont Auvergne (2021-...), 2022. http://www.theses.fr/2022UCFAL018.
Повний текст джерелаFor a long time, the relations between communication networks and castral sites have been associated with seigniorial taxation (tolls) or military activities (by stopping the trafic). Nevertheless, the coordination of roads, rivers, waterways and castles make appear many dynamic relationships between territories, their economic, political or social organization. The decisive question is to integrate these new perspectives into a representation of the practice of territories to define the real conditions of interrelationship between castral sites and communication networks during the end of the early medieval period and the late Middle Ages. The geographical framework of this thesis, the Lot valley from its source to its confluence, on a course of 485 kilometers (301 miles), allows us to consider the reciprocal permanence of social and spatial relations characterized by a plurality of political groups and struggles of influence between individuals. These different powers (great territorial princes, modest lordships, oligarchy and local aristocracy), whose seigniories and castral domains obtrude along this river, can make spaces, politics, societies and economy interact together to explain the dynamic phenomena that relate to the road, river and castles of the territories observed. This study is enriched by the analysis of archives collected, in nine departmental archive repositories, at the National Library of France (BnF), at the national archives of France or at the Public Record Office of London. This historical work focuses on the various actors of power bordering the Lot and their instruments of land domination in order to understand their logic of power and territorial management regardless of their social rank
Angius, Carolyn M. "The Concrete River: Industry, Race, and Green Justice on the Banks of the Los Angeles River." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/scripps_theses/291.
Повний текст джерелаLee, Weifeng Victoria. "Detour : Los Angeles River Speed Cinema." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/57978.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 158-163).
We live in the culture of speed; everything is on its way to become a faster version of itself tomorrow if it is not already there today. Automobile and cinema are two inventions at the turn of the 20th Century that brought upon entirely new sensations through their unprecedented speed in both physical and representational mobility. However, more than a century later in Los Angeles, a city where cars and movies have been inculcated in the popular imagination, decelerating to a complete halt or even nonexistence is the modus operandi of late. Today's LA. is full of cars with no where to drive them really fast; brimmed with cinematic mementos but no real place to watch a film. It does not help that most of the architecture associated with driving and movie-watching is meant to be experienced when slowed down, not sped up. It is time to pick up the pace. This thesis proposes a new cinema typology that amalgamates the physical speed of cars and the representational speed of films through a re-imagination of the mundane activities of driving and movie-watching in the Flood Control Channel in downtown Los Angeles.
by Weifeng Victoria Lee.
M.Arch.
Tran, Annie M. "Neustonic Plastic in the Los Angeles River." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/pomona_theses/54.
Повний текст джерелаZhang, Lu. "The Lost White Settlers in Michael Crummey's River Thieves." Thesis, Högskolan Kristianstad, Sektionen för Lärarutbildning, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-9215.
Повний текст джерелаChilds, Erin. "Take Me to the River: Revitalizing LA's Lost Monument." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/pomona_theses/56.
Повний текст джерелаDuffin, Jenna. "Effects of Engineered Log Jams on Channel Morphology, Middle Fork of the John Day River, Oregon." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19338.
Повний текст джерелаHarley, Craig Michael. "Denitrification Potential of Log Jams on the Sandusky River, Ohio :." Connect to this title online, 2005. http://hdl.handle.net/1811/305.
Повний текст джерелаTitle from first page of PDF file. Document formattted into pages: contains ii, 15 p.; also includes graphics. Includes bibliographical references (p. 15). Available online via Ohio State University's Knowledge Bank.
Le, Tran N. (Tran Ngoc). "Rethinking urban streams : opportunities for the Nhieu Loc -- Thi Nghe River." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44331.
Повний текст джерелаIncludes bibliographical references (p. 109-114).
In the process of rapid expansion, many cities have turned their backs on the rivers that helped form and nurture them. Due to the perceived low cost of their existing infrastructure, many rivers have become open or enclosed sewerage and drainage channels. In the past few decades, better scientific understanding and improved management practices have spurred a global river restoration and conservation movement. This thesis studies the paradigm shift from controlling urban streams as landscape features and liabilities to managing whole watersheds as ecosystems and assets. It examines examples of successful river restoration and conservation projects, and uses the lessons learned from these examples to suggest improvements to the management of the Nhieu Loc - Thi Nghe River in Ho Chi Minh City, Vietnam. The Ho Chi Minh City River Environmental Sanitation project of the late 1990s in the Nhieu Loc - Thi Nghe Basin was the first of its kind in Ho Chi Minh City. The project has been hailed as a successful urban regeneration project which exemplifies good practice. This thesis analyses the merits and missed opportunities of these projects and suggests ways to incorporate other ecological and cultural functions into the Nhieu Loc Thi Nghe River, drawing on lessons from successful river restorations in the United States and South Korea.
by Tran N. Le.
M.C.P.
Gobeau, Nathalie. "Modélisation d'un écoulement gaz-solide dans le riser d'un réacteur catalytique." Ecully, Ecole centrale de Lyon, 1998. http://www.theses.fr/1998ECDL0033.
Повний текст джерелаGroves, Christopher. "Lithologic Controls on Karst Groundwater Flow, Lost River Groundwater Basin, Warren County, Kentucky." TopSCHOLAR®, 1987. http://digitalcommons.wku.edu/theses/1554.
Повний текст джерелаLucano, Castillo Diego Alonzo. "Evaluación de los estacionamientos subterráneos en Rivera Navarrete." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2018. http://tesis.pucp.edu.pe/repositorio/handle/123456789/11731.
Повний текст джерелаTesis
Silva, Arredondo Eric Carlos. "Museo de los fenómenos Naturales – Malecón Rivera Monserrate." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/657049.
Повний текст джерелаConvinced that the ignorance of history and our environment, leads us to resolve by paths that remain and do not contribute; forgetting that nature provides; more does not punish. The following thesis project; `` Museum of Natural Phenomena - Malecón Rivera Monserrate '', is an architectural investigation that aims to unite the typologies of museum and boardwalk. The project seeks to be an example of the prevention of the `` disaster '', both for the exhibitions that do not pretend a false ecology, research areas and above all the volumetry. The latter, contemplates relating by containing the floods of the Rímac river, without imposing either the natural environment or the historical urban context of the city of Lima. For this, it will use construction elements, such as the cutwater, walkable roofs and equipment such as flooded orchards. The idea of using elements and constructive concepts, today forgotten; it is based on the use of three emphases; Environmental determinism, Calendar buildings and Feedback loops. The site to develop the project is located in the abandoned area of the Monserrate station, Cercado de Lima. The selection of the land is strengthened with two Municipal plans; The initiative for the recovery of Plaza Monserrate and the restoration of Lima 2035 heritage homes. The project aims to be a viable option after the development of Lima 2035.
Tesis
Rathburn, Sara L. "Pleistocene glacial outburst flooding along the Big Lost River, east-central Idaho." Thesis, The University of Arizona, 1989. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0127_sip1_w.pdf&type=application/pdf.
Повний текст джерелаGhole, Saba (Saba Ashfaq). "Field container as a regional strategy for revitalizing the Los Angeles River." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39304.
Повний текст джерелаIncludes bibliographical references (p. 121).
This thesis is the study of the Los Angeles River as a multi-layered field with urban condensers that revitalize the river, connect and revitalize the municipal districts bordering the river, and restructure the region to support a denser fabric. The project establishes the nature of public space in the city as a highly contested sphere of multiple interests and constituencies and utilizes the river as a platform to engage these tensions. The Los Angeles River epitomizes the artificiality and ingenious of Los Angeles as a city which molded its environment to suit its will, inhabiting a dry, arid desert and structuring one of the largest metropolises in the world. The merging of these two instances, the particular geography of Southern California and man's desire and ingenuity to overcome this nature by man's engineering is the story of how Los Angeles became a global city from an agricultural village. With a population approaching four-million inhabitants, the city is examined after the Southern California development phenomena of "dense sprawl" and is used as a model to examine the future potential of the river, currently a mono-functioning, concretized flood control channel, to become a multi-functioning infrastructure mediating a density of program and flows at the regional, metropolitan and local scales.
(cont.) The thesis examines the river's stretch from the Glendale Narrows through downtown to the city of Vernon and the creation of a public landscape armature with six urban condensers, areas designed according to a set of criteria that challenge the current condition of urban infill and the erasure of public open space. The expectation is that these projects will engage the socio-economic complexity of Los Angeles and overcome the limitations posed by jurisdictional boundaries.
Saba Ghole.
S.M.
Cretella, Francis Michael. "A Preliminary Investigation of the Effect of Storm Events on the Concentration of Volatile Organic Compounds in the Lost River Cave System, Warren County, Kentucky." TopSCHOLAR®, 1985. http://digitalcommons.wku.edu/theses/1665.
Повний текст джерелаAbrahamse, Matthew S. "Abundance and structure of burbot Lota lota populations in lakes and reservoirs of the Wind River drainage, Wyoming." Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1797714301&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Повний текст джерелаHoebbel, John Marshall. "The View From Below: Encountering Urban 'Lost Space'." Cincinnati, Ohio : University of Cincinnati, 2009. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1245767184.
Повний текст джерелаAdvisor: Vincent Sansalone. Title from electronic thesis title page (viewed Aug. 3, 2009). Includes abstract. Keywords: infrastructure; terrain; vague; lost; space; levee; river; architecture; marginal; bridge; covington. Includes bibliographical references.
Bolingbroke, David. "Restoring the Lost Fishery: An Environmental History of Northern Nevada's Pyramid Lake and Lower Truckee River Fishery." DigitalCommons@USU, 2014. https://digitalcommons.usu.edu/etd/3290.
Повний текст джерелаStefanovič, Violeta. "Šikšnosparnių (Chiroptera) rudeninės migracijos tyrimai Oderio upės slėnyje pietvakarių Lenkijoje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2011~D_20141223_174652-81195.
Повний текст джерелаWe studied migration of bats along Odra river valley in SW Poland for four nights in September 2010. We carried out all-night acoustical observations of bats flying at the river North-Soutth and East-West directions segments, in the forest, grassland and on the outer wood. The direction on bats’ movements were determined on the basis of echolocation sequences order recorded by two frequency division ultrasound detectors. We noted activity for eight species: Myotis daubentonii, M. dasycneme, M. brandti, Nyctalus noctula, Pipistrellus nathusii, P. pipistrellus, P. pygmaeus, Eptesicus serotinus. Our results show that Myotis daubentonii, Pipistrellus nathusii, P. pygmaeus use only the river as the migration corridor, but not all valley of the river. Eptesicus serotinus and P. pipistrellus directional flyings were detected in the forest, but these data were unsufficient to relate the migratory way and the valley of the river. The great amount of undirectional flyings and nutrition signals of Nyctalus noctula in all places shows that this species uses all the valley for nutrition. Our results show that the activities of different bats species for twenty four hours are different at the river. The greatest counts of sequencies for Myotis daubentonii, Nyctalus noctula were registered in the evening: Myotis daubentonii – at 8 p.m., and Nyctalus noctula – at 7 p.m. Activities of Pipistrelus pygmaeus and Pipistrellus nathusii were similar during all night time. No activities of bats were... [to full text]
Patterson, Scott Joseph. "Sedimentology and Geomorphology of Quaternary Alluvial Fans with Implications to Growth Strata, Lost River Range, Idaho." Thesis, Montana State University, 2006. http://etd.lib.montana.edu/etd/2006/patterson/PattersonS0806.pdf.
Повний текст джерелаArroyo, John C. (John Christopher). "Culture in concrete : art and the re-imagination of the Los Angeles River as civic space." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59727.
Повний текст джерелаCataloged from PDF version of thesis.
Includes bibliographical references (p. 237-245).
The Los Angeles River is the common physical, social, and cultural thread that connects many of Los Angeles' most diverse and under-represented communities, the majority of which comprise its downstream corridor. It is a valuable resource that crosses boundaries of race, class, geography, and culture. Once a natural and alluvial river, a series of devastating floods led the Army Corps of Engineers to pave the 52-mile River with concrete in the 1930s. The River has been forgotten, abandoned, degraded, and largely misunderstood by many ever since. Artists have taken to the River as a creative venue. Their actions have re-defined the River and have allowed us (and impel us) to re-imagine the River as the civic space that Los Angeles is desperately seeking, but has yet to find, despite many unsuccessful attempts. This thesis examines the patterns, motivations, and history behind over 40 largely unheralded art projects over a 20-year period along the River's Glendale Narrows, Lower Arroyo Seco, and downtown Los Angeles segments. It illustrates why generations of artists from all disciplines have been inspired to engage with the River's concrete form and abandoned. From photography to site-specific dance, poetry to new media, these artists have reveled in the un-designed, un-planned, and the spontaneous nature of the River space. They have expressed themselves through place-based work, most of which has been independent of any formal urban planning, urban design, or public policy support or intervention. While this thesis acknowledges contemporary master planning efforts currently underway to transform the River, it makes a case for the power of under-represented groups (artists) to create value outside of traditional, formal, and normative urban planning and design interventions reliant on government support, public-private partnerships, and corporate interests. Furthermore, this thesis provides a review of popular critiques and previous interpretations of civic space in Los Angeles. It reviews Los Angeles' transition from a once mobile, accessible, and largely homogenous city to one of the world's most diverse and park-poor metropolises without a strong civic space. This thesis provides examples of the Los Angeles' recent and future attempts to create civic space in downtown Los Angeles and offers alternatives from domestic and international cases reflecting the principles of landscape urbanism, everyday urbanism, and temporary urbanism. By engaging with the River as space for critical human and cultural expression, the research in this thesis suggests that artists are offering key insights for how to plan, design, and re-imagine the Los Angeles River as civic space.
by John C. Arroyo.
M.C.P.
Boum, Alexandre Teplaira. "Commande prédictive d'un craqueur catalytique à lit fluidisé avec estimation des paramètres clés." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0033/document.
Повний текст джерелаFluid catalytic cracking (FCC) is one of the most important processes in a modern refinery and is of essential economic importance. The FCC operation presents difficulties related to its complexity. The study was related to its simulation, multivariable control and estimation of key parameters. After a litterature review of the FCC, the different approaches of modelling and cracking kinetics, a FCC model that takes into account the important dynamics was chosen for model predictive control purposes. The riser simulation was carried out for different cracking models and shows great differences between these models, which makes it difficult to define a general riser model for the FCC. Besides the number of lumps, differences deal with the global heat of reaction, the coke formation laws and its deactivation functions. Linear and nonlinear model predictive algorithms were used for FCC control taking into account its multivariable nature and the constraints imposed on the manipulated variables. The controlled outputs, temperature at the riser top and temperature in the regenerator were maintained close to their respective set points in regulation and tracking modes while respecting the constraints on the two manipulated variable, the flow rate of regenerated catalyst and the flow rate of air entering the regenerator. A control with three manipulated variables including the feed flow rate was also successfully tested. Linear predictive control with an observer gave better results than linear quadratic control. Nonlinear predictive control was tested but presents problems for real time implementation. The estimation of coke on the catalyst was carried out using extended Kalman filter, but the estimation errors are important, probably due to an insufficient choice of measurements. The overall study showed that advanced predictive control of the FCC is efficient and must be recommended, but it can still be improved upon particularly by its tuning and state estimation
Venegas, Pardo Luis Felipe. "Recuperación rivera norte Calle Calle : las Animas, Valdivia Región de los Ríos." Tesis, Universidad de Chile, 2008. http://www.repositorio.uchile.cl/handle/2250/112942.
Повний текст джерелаNo autorizada por el autor para ser publicada a texto completo
La intención de trabajar en la ciudad de Valdivia nace en primer lugar, por el interés personal de captar las oportunidades de desarrollo de esta misma, debido a su declaración en el año 2007 como capital regional de la nueva Región de los Ríos. Esta nueva categoría afecta no solo a la ciudad en términos administrativos sino también se espera un fuerte impacto en temas urbanos y de infraestructura para los requerimientos del nuevo gobierno regional. Por otro lado, la búsqueda de la temática a desarrollar fue guiada por el interés de trabajar en áreas de deterioro en la ciudad, causada principalmente por el abandono de tales lugares o dificultad de acceso, con el fin de rehabilitarlas y así integrarla al resto de la trama urbana respondiendo a las necesidades tanto del lugar como de su entorno y la ciudad. Es por eso, que este proyecto se centra principalmente en este tema, ya que Valdivia ha experimentado profundos y constantes cambios desde su fundación. Además, se quiso considerar las necesidades de desarrollar proyectos de suelo urbano para la generación de nuevas áreas habitacionales, ya que en la actualidad esta actividad se esta desarrollando en sectores lejanos al centro. Esto, genera una discontinuidad de la trama urbana además de una ineficiencia tanto de los sistemas de transporte debido a los largos tramos que deben recorrer, aumentando el tiempo de viaje de sus habitantes, como en la necesidad de crear infraestructura de servicios ya existentes en el área central. El proyecto busca hacerse cargo de la franja de desarrollo, generando un proyecto respetuoso con el ecosistema colindante, que responda a las necesidades y vocación del lugar. Además Recuperar , Sanear e Integrar humedal protegido por el plan regulador. A partir de esto se establecen los criterios de intervención al lugar por lo cual respondiendo al primero se propone el desarrollo de un proyecto de viviendas que se haga cargo de la demanda inmobiliaria esperada para el sector y en conjunto dar un espacio para reubicar a las familias del campamento Arturo Prat a viviendas de mejor calidad, manteniendo y generando nuevas redes sociales junto a su arraigo al lugar ya que su traslado no es mayor a 3 manzanas desde su ubicación actual, en la que permanecen desde hace muchos años de manera ilegal en terrenos del Serviu Regional.
Kennedy, Patrick Allen. "The Effect of Irrigation Diversions on the Mountain Whitefish Population (Prosopium williamsoni) in the Big Lost River." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/512.
Повний текст джерелаRusso, Rebecca Anne. "A study of the seismic performance of the Los Angeles River floodcontrol channel during the 1994 Northridge earthquake." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-12302008-063145/.
Повний текст джерелаHancock, Quentin Webster. "From conviction to recreation : Earth First!, Friends of the Los Angeles River and the culture of American environmentalism /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.
Повний текст джерелаLitvinaitis, Andrius. "The evaluation of the influence of coastal sediments on river water quality." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130619_125148-43041.
Повний текст джерелаDisertacijoje nagrinėjamos biogeninių medžiagų migracijos Lietuvos upių pakrančių nuogulose ypatybės ir jų įtaka upių vandens kokybei. Tyrimų objektu pasirinkti šeši skirtingose Lietuvos hidrologinėse srityse esantys tipingų nuogulų upių baseinai. Toks objektų pasirinkimas leidžia darbo rezultatus taikyti bet kuriame Lietuvos upės baseine. Disertacijos tikslas – atsižvelgiant į klimatines bei upės baseino geomorfologines sąlygas nustatyti biogeninių medžiagų migracijos ypatybes nuogulose, gruntiniuose ir paviršiaus vandenyse, siekiant įvertinti biogeninių medžiagų koncentracijų kaitą upių pakrančių skirtingų nuogulų aeracinėse zonose ir jos įtaką upių vandens kokybei. Darbe analitiniais, natūriniais ir eksperimentiniais tyrimais, matematiniu modeliavimu įvertinami biogeninių medžiagų koncentracijų kaitos dėsningumai upių baseinuose ir pakrantėse. Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai. Įvadiniame skyriuje suformuluota tiriamoji problema, darbo aktualumas, tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, darbo mokslinis naujumas, darbo rezultatų aprobavimas, ginamieji teiginiai. Įvade pateiktos autoriaus disertacijos tema paskelbtos publikacijos ir pranešimai konferencijose bei disertacijos struktūra. Pirmame skyriuje pateikta mokslinės literatūros biogeninių medžiagų migracijos gamtoje, upės baseino teritorinės struktūros įtakos tyrimų, Lietuvos upių vandens kokybės... [toliau žr. visą tekstą]
Da, silva Rodrigues Sofia. "Riser hydrodynamic study with Group B particles for Chemical Looping Combustion." Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10230/document.
Повний текст джерелаChemical Looping Combustion (CLC) is an oxy-combustion like process where particles are used to supply oxygen to combustion. Further work is still needed for extrapolation and optimization of the CLC process, concerning properties of Group B particles and CFB technology. Hydrodynamic tests were made on a 18 m tall riser. Axial pressure profiles as well as radial flux profiles and radial momentum quantity profiles were obtained. Three types of Group B particles were used with Sauter mean diameters between 250 and 300 μm and densities between 2600 and 3300 kg/m²s. An important impact of particle sphericity on riser pressure drop has been revealed. At identical conditions, glass beads present about half the pressure drop generated by sand. In the developed region of the riser, the core-annulus regime has been found. A 1D model of the riser, based on experimental results and on the Euler-Euler gas-solid equations, has been developed. Moreover, a new cross section averaged drag force correlation is presented. A new boundary condition on the bottom of the riser has been investigated. The final 1D model is capable of predicted riser pressure drop from the operating conditions and it takes into account particle properties such as density, size and shape. A study on the adequacy of the use of the commercial CFD code Barracuda to simulate risers with Group B particles was made. It was shown that the code under estimates pressure drop along the riser for sand simulations
Lawhon, Nicholas. "Investigating Telogenetic Karst Aquifer Processes and Evolution in South-Central Kentucky, U.S., Using High-Resolution Storm Hydrology and Geochemistry Monitoring." TopSCHOLAR®, 2014. http://digitalcommons.wku.edu/theses/1324.
Повний текст джерелаFERRACCI, GABRIELE. "On the River Road. In viaggio sui fiumi dell'Ovest, 1803-1861." Doctoral thesis, Università degli studi di Genova, 2019. http://hdl.handle.net/11567/986267.
Повний текст джерелаGómez, Acuña Luis. "Peralta Rivera, Germán. Los mecanismos del comercio negrero. Kuntur Editores, Lima 1990, 391 p." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/121524.
Повний текст джерелаMillay, Curtis A. "Restoring the Lost Rivers of Washington: Can a city's hydrologic past inform its future?" Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/31770.
Повний текст джерелаMaster of Landscape Architecture
Vincent, Kirk Robert, and Kirk Robert Vincent. "IMPLICATIONS FOR MODELS OF FAULT BEHAVIOR FROM EARTHQUAKE SURFACE-DISPLACEMENT ALONG ADJACENT SEGMENTS OF THE LOST RIVER FAULT, IDAHO." Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187565.
Повний текст джерелаJordà, Capdevila Dídac. "Water flows to multiple stsakeholders: an ecosystem services-based approach to conflicts in the Ter River basim." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/393917.
Повний текст джерелаConflicts related to water flows are the subject of abundant intellectual outputs. However, analysis of their relation to the appropriation of instream flow–dependent ecosystem services (ES) is missing. Such analysis, undertaken with a proper regard for stakeholders’ views and interests, is the objective of this thesis. As happens in other Mediterranean contexts, multiple water withdrawals from the Ter River (NE Catalonia, Spain), in particular for hydropower production and the supply of the metropolitan Barcelona, disrupt instream flows and hence damage the river ecosystem. Traditionally, this situation has triggered local and regional disputes, becoming a main issue for water management in the basin district. This dissertation involves three types of ES applications. First, we identify and characterise multiple ways people use, enjoy and feel the river. This is done by a scrutiny of those hydrological alterations and components of nature that have an effect, positive or negative, on them. Second, an ES provision model is coupled with a water allocation model in order to quantify and establish a valuation of the ES under different water management and climate scenarios. Finally, the ES provision is studied for a period of 65 years, by analysing who has been who in the exercise of power for controlling the access to water flows and the ensuing ES. That historiographical research combines qualitative data from the archives (e.g., letters, news) and quantitative data of instream flows and dam management. In the course of the study, the engagement of all types of stakeholders – both key informants and water activist organisations – has been an essential aspect of the methodology. Field research undertaken between 2011 and 2015 included dozens of interviews with key stakeholders, the organisation of five workshops and two surveys. The results show that, with the proper provisions, our ecosystem services-based approach: 1) helps to engage with stakeholders, reconnecting people to water management; 2) unveils less conspicuous ES, whose beneficiaries are usually misrepresented in decision-making spheres; 3) disentangles the complexity of societal-ecological relationships and shows the adaptation of river users to different levels of river alteration; 4) illustrates unequal distribution of benefits among different ES, over time and space and under different water management and climate scenarios; and 5) when used with a critical historical perspective, it discloses those power relationships that hamper the implementation of management measures that reduce the water extraction pressure on the river in support of an environmental flow regime.
Gulbinaitė, Raminta. "PAKRUOJO MIESTO ĮTAKA KRUOJOS UPĖS TARŠAI." Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100903_002409-39127.
Повний текст джерелаEnvironmental and professional safety bachelor subject is relevant, because water pollution is one of the most cause of concern for environmental issues. The river water is the main object of Lithuania, which connects the internal waters of the Lithuanian population is an important part of the water cycle. In order to maintain a good ecological status of river water, it is necessary to protect and conserve the rivers from pollution by harmful substances that impair the chemical and microbiological quality of river water. Therefore analysis of one of the Lithuanian city of influence - urban of Pakruojis influence of pollution in the river. One of the reasons for the contamination is precipitation, rain water, which blows directly into the river. To avoid this pollution there is need to rain water to get underground networks, and purified from contaminants released into the open river of Kruoja, installation of surface water biological treatment ponds on the river, to ensure normal traffic within the city by the strong rain. Purpose of the research. Influence of Pakruojis urban river of Kruoja pollution. Research methodology. In this work the scientific literature, surface water protection. Described hydrochemical assessment of rivers. Provided knowledge about the state of the river of Kruoja. Analyze river of Kruoja surveys. Describe the chemical water quality parameters for the quantitative analysis methods waste management regulatory documents. Final results of the reseach... [to full text]
Baize, David. "A “Drastic” Evaluation of the Ground-Water Pollution Potential of Karst Terrain: Lost River Ground-Water Basin, Warren County, Kentucky." TopSCHOLAR®, 1990. http://digitalcommons.wku.edu/theses/1889.
Повний текст джерелаRuminaitė, Rasa. "Research and evaluation of the anthropogenic activity impact on the river runoff and water quality." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20101222_130626-88044.
Повний текст джерелаDisertacijoje nagrinėjama antropogeninės veiklos įtaka upių nuotėkiui ir vandens kokybei. Tyrimo objektas yra tarptautinis, antrasis pagal dydį Lietuvoje Lielupės upių baseinų rajonas (UBR). Išskirtiniai Lielupės UBR bruožai – ypač intensyviai vykdoma žemės ūkio veikla ir aktyviai vykstantys karstėjimo procesai. Pagrindinis tyrimų tikslas – įvertinti antropogeninės veiklos Lielupės upių baseinų rajone kaitos tendencijas ir įtaką upių nuotėkiui bei vandens kokybei, atsižvelgiant į gamtosauginius ir Europos Sąjungos direktyvų, Lietuvos Respublikos įstatymų ir poįstatyminių aktų reikalavimus vandens kokybei. Darbe sprendžiami šie uždaviniai: pernelyg drėgnų žemių sausinimo įtaką upių vandeningumo kaitai, antropogeninės veiklos sąlygotos sutelktosios ir pasklidosios taršos poveikis upių vandens kokybei. Disertaciją sudaro įvadas, šeši skyriai, bendrosios išvados, rekomendacijos, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai. Įvadiniame skyriuje aptariama tiriamoji problema, aktualumas, tyrimų objektas, darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, ginamieji teiginiai. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos bei disertacijos struktūra. Pirmasis skyrius skirtas literatūros apžvalgai. Jame pateikta antropogeninės veiklos įtakos upių nuotėkiui ir biogeninių medžiagų migracijai analizė. Analizuojamas matematinio modeliavimo vaidmuo upių kokybės išsaugojimo procese. Apibūdinamos... [toliau žr. visą tekstą]
Burfeid, Castellanos Andrea Montserrat. "Ecological factors and diatom diversity at rivers of the iberian mediterranean river basins: macro-scale, meso-scale and micro-scale = Factores ecológicos y diversidad de diatomeas en los ríos de las cuencas hidrográficas del Mediterráneo ibérico: maro-escala, meso-escala y micro-escala." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663475.
Повний текст джерелаLas diatomeas bentónicas son organismos fotoautotróficos unicelulares, acuáticos y colonizadores de sustratos, que se han usado en bioindicación por ser buenas indicadoras del estado ecológico del agua. En esta tesis hemos estudiado cómo las diatomeas de ríos ibéricos mediterráneos se ven afectadas por la ecología del medio donde habitan, a diversas escalas. Estos organismos se estudiaron a nivel taxonómico e indicativo, funcional y morfométrico. La estructura de esta tesis sigue una aproximación a la reducción de escala de trabajo. El capítulo de macro-escala se basó en una investigación de las comunidades bentónicas epilíticas de las diatomeas del río Ebro, en base a muestreos realizados a lo largo de 10 años. Este estudio se ha demostrado que la división en ecotipos fluviales establecida para el seguimiento de la Directiva Marco del Agua (DMA) no coincide con la diversificación delascomunidades deestosorganismos. Nuestrosresultados apuntanqueunaaproximacióndoble (composición físico-química y estructura de la comunidad) puede reflejar mejor la realidad para las diatomeas. En el capítulo de meso-escala se investigó el río Segre con la finalidad de establecer las relaciones entre los usos del suelo y las comunidades de diatomeas y valores de los índices de diatomeas. Los usos del suelo afectan directamente a la composición del agua fluvial. Por ello, se esperaba una correlación entre el uso del suelo aguas arriba de las comunidadesde diatomeas estudiadas. Los resultados muestranque únicamentelos usos mayoritarios afectan la composición las comunidades de diatomeas y los valores de los índices diatómicos. En el capítulo de microescala se estudió la reacción de las diatomeas en cada punto. Para ello el capítulo se dividió en tres secciones. Un experimento observó el efecto de puntos intrínsecamente diferenciales sobre las formas de vida, y cambios de estas tras su translocación. La otra sección comparó la composición funcional de la comunidad de diatomeas en ríos temporales, que sufren pérdida parcial o total del agua superficial. Finalmente, aún en microescala, se fotografiaron automáticamente muestras de diatomeas del río Ebro para calcular sus características morfométricas. Estas se relacionaron con los parámetros fisicoquímicos de cada punto y con su variabilidad temporal. El resultado fue una clara afectación de tamaños valvares según la composición del agua. La relación superficie-volumen estaba altamente correlacionada y la anchura valvar, obviada hasta ahora, se vio afectada por los parámetros fisicoquímicos.
Les diatomees bentòniques, organismes fotoautotròfics unicel·lulars, aquàtics i colonitzadors de substrats, que s’han utilitzat a la bioindicació per ser bones indicadores del estat ecològic de l’aigua. En aquesta tesi hem estudiat com les diatomees de rius ibèrics mediterranis es veuen afectades per l’ecologia del medi al que habiten a diverses escales. Aquests organismes es varen observar a nivell taxonòmic-indicatiu, funcional i morfomètric. L’estructura d’aquesta tesi segueix una aproximació a la reducció d’escala de treball. El capítol de macro-escala es basà en una investigació taxonòmica de les comunitats bentòniques epilítiques de diatomees del riu Ebre, basat en mostrejos realitzats al llarg de 10 anys. Aquest estudi ha mostrat que la divisió d’ecotips fluvials establerta per a el seguiment de la Directiva Marc de l’Aigua (DMA) no coincideix amb la diversificació de les comunitats d’aquests organismes. Els resultats assenyalen que una aproximació doble (composició fisicoquímica i estructura comunitària) podria reflectir millor la realitat per a les diatomees. Al capítol de meso-escala s’estudià el Segre per tal d’establir les relacions entre els usos del sòl, les comunitats de diatomees i els seus valors indicadors. Els usos del sòl afecten directament a la composició de l’aigua fluvial. Per això, s’esperava una correlació entre els usos del sòl aigües amunt de les comunitats de diatomees estudiades. Els resultats mostren que únicament els usos majoritaris afecten els la composició de les comunitats de diatomees els i valors dels índexs diatòmics. El capítol de micro-escala investigà la reacció de les diatomees a cada punt. Per això, el capítol es dividí en tres seccions. Un experiment observà l’efecte de punts intrínsecament diferencials sobre les formes de vida i canvis d’aquests després de la translocació. L’altra secció comparà la composició funcional de la comunitat de diatomees a rius temporals, que pateixen la pèrdua total o parcial de l’aigua superficial. Finalment, seguint a la micro-escala, es fotografiaren les mostres del riu Ebre automàticament per calcular les seves característiques morfomètriques. Aquestes es relacionaren amb els paràmetres fisicoquímics de cada punt i la seva variabilitat temporal. El resultat fou una clara afectació de mides valvars segons la composició de l’aigua. La relació superfície-volum estava altament correlacionada amb les variacions fisicoquímiques i l’amplada valvar, obviada fins ara, era afectada pels paràmetres fisicoquímics.
Merino, Silicani de Alvarez Rosanna María Victoria Andrea. "La propuesta reformista de María Jesús Alvarado: de los ensayos a la novela." Master's thesis, Pontificia Universidad Católica del Perú, 2019. http://hdl.handle.net/20.500.12404/16710.
Повний текст джерелаDupuis, Victor. "Étude expérimentale d’écoulements soumis à une transition longitudinale de rugosité en lit simple et en lit composé." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1154/document.
Повний текст джерелаThis PhD thesis investigates the effect of a longitudinal change in floodplain land use on an overflooding river flow. We consider a transition between a meadow and a woodland and vice versa. This change in land use is associated with a change in hydraulic roughness, between a bed roughness (highly submerged meadow) and emergent macro-roughnesses (trees), respectively modelled by a plastic artificial grass and an array of emergent cylinders. The flows are experimentally investigated in an 18 m x 3 m laboratory flume. In a first step, we investigate the flow through a cylinder array in a single channel, focusing on the effect of bed roughness on the cylinder wakes and on the seiche phenomenon (strong free surface oscillations). In a second step, we study the development towards flow uniformity of compound channel flows with a uniform hydraulic roughness on the floodplains. The asymmetrical growth of the compound channel mixing layer, the self-similarity property and the three-dimensional organisation of the turbulent coherent structures associated with the mixing layer are analysed. In a third step, we investigate the longitudinal change in roughness in compound channel configuration, which effects on mixing layer and on coherent structures are discussed. We also assess the contributions to lateral transfers of momentum between main channel and floodplain by turbulent diffusion, by mass exchange and by secondary currents
Lopez, Seir Garcia-Corales Guillermo. "Gestos posmodernos en la novela latinoamericana : los casos de Cristina Rivera Garza, Ana Maria Shua y Laura Restrepo /." Waco, Tex. : Baylor University, 2006. http://hdl.handle.net/2104/4014.
Повний текст джерелаLeonardo, Pérez Yazmin Mercedes, and Dall’Orso Antoinette Ormeño. "La traducción del fenómeno de la transculturación narrativa en Los ríos profundos/ Deep Rivers de José María Arguedas." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/652391.
Повний текст джерелаNarrative transculturation is a phenomenon that entails creating new products due to the incorporation of cultural and linguistic elements to a dominant culture and their loss on the dominated one. These elements are expressed through language, literary structure and worldview. During the translation process, translators make different kind of decisions in order to create a target text that includes the same cultural equivalence that the original text already has. When a transcultural text is translated, specific procedures are needed to achieve the most accurate rewording of the source text on the final product which, at the same time, seeks for the understanding of the target audience. Therefore, the following research focuses on the analysis of the narrative transcultural translation phenomenon on Deep Rivers, written by José María Arguedas and translated by Frances Horning Barraclough. In addition, the aim of this investigation is to identify the transcultural elements in Los ríos profundos with the purpose of recognizing the translation techniques and analyze the use paratexts during the translation process. In this investigation, in order to identify and analyze transcultural elements in Los ríos profundos, content analysis technique will be use through the elaboration of the codification book. Furthermore, the contrastive textual analysis technique will be applied through index tabs to show fragments, lexemes and syntagmas of both the source and target text. As a result, the procedures that Frances Horning Barraclough used for the translation of the transcultural elements in Los ríos profundos will be presented.
Trabajo de investigación
Ravazzolo, Diego. "NATURE AND DYNAMICS OF LARGE WOOD AND INTERACTIONS WITH VEGETATION IN GRAVEL-BED RIVERS." Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3424631.
Повний текст джерелаFino poco tempo fa, i fiumi sono stati considerati come il risultato dell’interazione tra acqua e sedimenti, semplificando così il complesso sistema fluviale e tralasciando un importante componente: la vegetazione. Questa componente comprende alberi ed arbusti che crescono sulle barre, isole, sponde e sulle pianure alluvionali; così come gli elementi legnosi morti che giacciono sul letto del fiume. Sia la vegetazione viva che quella morta esercitano un importante ruolo sulla morfologia e la dinamica di un sistema fluviale. Inoltre, evidenze hanno dimostrato la sua importanza ecologica attraverso la creazione di habitat per una varietà di organismi. Oltre agli aspetti positivi che il materiale legnoso in alveo può apportare, è fondamentale tenere in considerazione il potenziale pericolo connesso al suo trasporto durante eventi di piena di elevata magnitudo. Il materiale legnoso, ad esempio, può essere un fattore di pericolo per le strutture sensibili come i ponti, nonché lungo le sezioni trasversali soggette ad esondazione. Per queste ragioni ed altri problemi idraulici, così come l’incremento della rugosità, la tradizionale strategia di gestione della rete fluviale adottata, è stata quella di rimuovere dall’alveo il materiale legnoso morto e tagliare la vegetazione da isole e piane alluvionali. Evidenze di recenti ricerche, hanno dimostrato i positivi effetti che il legname esercita in alveo. Queste osservazioni, suggerirono di intervenire sulle strategie di gestione, agendo sulla reintroduzione del legname in alveo. Tuttavia, è evidente la necessità di rivisitare la gestione del legname nei sistemi fluviali e delle aree ripariali, le quali sono potenziali fonti di legname in alveo. Di fondamentale importanza, per raggiungere tale obbiettivo, è la determinazione delle dinamiche del materiale legnoso presente in alveo e delle interazioni di esso con la vegetazione ripariale. In questo elaborato di tesi vengono svolte delle prime analisi in campo, necessarie per valutare se le diverse pressioni antropiche in un sistema fluviale, hanno conseguenze sulla natura del materiale legnoso in alveo. I fiumi in considerazione sono, dal più al meno antropizzato, il fiume Brenta, Piave e Tagliamento. Inoltre, attraverso analisi sulla distanza e velocità di spostamento di alcuni elementi legnosi durante eventi di piena di diversa magnitudo nel fiume Tagliamento, si vuole incrementare la conoscenza dei processi di trasporto e deposizione del materiale legnoso in larghi fiumi ghiaiosi. Vista la simultaneità delle dinamiche osservabili in campo tra vegetazione e legname in alveo, risulta opportuno ricorrere ad analisi di laboratorio in modo da riuscire a scindere le due componenti. La serie di simulazioni, condotte in una canaletta artificiale, hanno lo scopo di rappresentare un significativo contributo alla comprensione degli effetti reciprocamente connessi tra la vegetazione e legname in alveo, nel contesto della morfologia fluviale. Con questo elaborato di tesi si vuole esprimere un importante punto di inizio per un migliore approccio alla gestione del materiale legnoso nei sistemi fluviali, aumentando le conoscenze sulle sue dinamiche ed interazioni con la vegetazione ripariale in fiumi ghiaiosi.
Gegužis, Ramūnas. "Impact of flow energy distribution on the ecological status of rivers." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2013~D_20131218_133501-16390.
Повний текст джерелаDarbo tikslas – ištirti vandens tėkmės energijos pasiskirstymo ir upelių vagų sąveikos dėsningumus, vykstant natūralizacijos procesams, nustatyti morfometrinius pokyčius upelių vagose lemiančius veiksnius ir įvertinti jų poveikį upių ekologinei būklei. Darbo tikslui pasiekti buvo sprendžiami 6 uždaviniai: 1) taikant natūrinių tyrimų rezultatus, sudaryti geostatistinius reguliuotų ir natūralių vagų hidromorfologinių charakteristikų modelius; 2) pasinaudojus gautais modeliais, nustatyti morfometrines vagų charakteristikas; 3) pasinaudojus gautais modeliais, išsiaiškinti tėkmės energijos pasiskirstymo ir jos sąveikos su upelių vaga dėsningumus; 4) ištirti žolinės ir sumedėjusios augalijos gausą ir jos sudėtį tiriamų upelių atkarpose; 5) nustatyti makrozoobentoso ir juo besimaitinančių žuvų rūšinę įvairovę, sudėtį ir gausą; 6) išsiaiškinti tėkmės energijos pasiskirstymo ir upelių vagų sąveikos įtaką upių ekologinei būklei.
Aalto, Rolf Erhart. "Geomorphic form and process of sediment flux within an active orogen : denudation of the Bolivian Andes and sediment conveyance across the Beni Foreland /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/6718.
Повний текст джерелаDonauskaitė, Eglė. "Požeminio vandens išteklių baseininio valdymo ypatumai." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110207_105114-51339.
Повний текст джерелаLithuania had to implement the requirements of EU directives when water policy was being implemented. The Water Framework Directive provides supervision and protection of the entire water circuit and requires to implement the river basin management system. This system joins the river basins and the bodies of groundwater, which have no link in the territory of Lithuania. In addition, the borders of both the river basins and the bodies of groundwater do not coincide. Lithuania differs from the majority of other European states because it has favourable geological and climatic conditions that account for the accumulation of abundant groundwater resources – only resources used for drinking water supply. Therefore the protection of groundwater is very important in Lithuania because it is only source of drinking water in this country. The aim of fhe final Master‘s work is to analyse the river basin management of groundwater resources and its implementation and peculiarities in Lithuania. To reach this aim the present river basin management system of groundwater resources has been analysed and the efficiency of this system has been exposed. The hypothesis that the river basin management of groundwater resources in Lithuania is not efficient and it can not help to reach the aims setted for groundwater resources in The Water Framework Directive is confirmed. The opinion of the experts is provided in the work and mainly in its last part. The conclusions and the proposals are... [to full text]
Ferreira, de Carvalho Rui Filipe. "Análisis multi-proxy paleoambiental y modelización de registros sedimentarios fluviales en los Alpes Suizos." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/287059.
Повний текст джерелаThe study of fluvial systems by means of sediment cores is one of the most interesting approaches to understand the spatial and temporal pattern of river dynamics under the influence of different driving forces such as climate variability and human activities. This work focuses on the analysis of the sedimentary dynamics of two delta plains from the Bernese Alps. In the lower Hasli valley a multi-proxy paleoenvironmental analysis of fluvial and alluvial sediments was conducted, allowing the reconstruction of the interactions of climate variability in river systems and changes in land use. The research combines stratigraphical and geochemical analysis of sediment cores. Other approach focused on modeling sediment aggradation in the Hasli valley and in the Lütschine delta plain. An estimation of soil erosion and transport in tributary watersheds was also conducted in both of the mentioned delta plains. The results of the geochemical analysis from the Aare sediments showed periods of increased sediment agradation that are associated with cold climatic phases, whereas organic rich soil formation occurred during warmer periods. The development of a metal anomaly index provided evidences of phases of mining activity during the Roman Period and the Early Middle Ages, as well as a general increase of metal concentration during the Modern Era. The volume and temporal distribution of aggradation in delta plains indicates the absence of a significant increase of accumulation during the last 1000 years, despite strong human intervention. This may be due to an efficient water management by local communities that were able to implement structural mitigation measures in river channels (embankment) that bypass the majority of transported sediments towards Lake Brienz. A first approach was made in the quantification of erosion and river transport in tributary watersheds of the Aare and Lütschine delta plains. The results indicate some inconsistencies in relation to the geomorphological landforms, since they are unable to explain the high variability of erosion and transport in alpine sedimentary environments. However, the data obtained evaluate the applicability of RUSLE model in mountain regions and allowed the analysis of erosion coefficient and land use importance on the estimation of potential soil erosion.
Smith, Christy A. "Lost Cove, North Carolina: The Life and Death of a Thriving Community (1864-1957)." Digital Commons @ East Tennessee State University, 2007. https://dc.etsu.edu/etd/2147.
Повний текст джерелаSchmutz, Hélène. "Vers une redéfinition de la nature américaine : trois études de cas dans la région de Los Angeles." Thesis, Paris 4, 2013. http://www.theses.fr/2013PA040149/document.
Повний текст джерелаEnvironmental historians have worked at redefining the modes of relationship between man and nature in the United States. The way this relation is defined conditions environmental politics, and therefore contributes to the material transformation of the continent. Five major trends of thought about nature are described: nature as a resource transformed by work ; preservationism ; conservationism ; ecology ; and environmental justice. Those ideas endure to this very day in the discourses constructed about nature: they either juxtapose or confront each other. The goal of this thesis is to understand whether they undergo a transformation, evolving towards a definition of the man/nature relationship as a socionatural hybrid. To this end, three cases are examined here, all of which are connected with the Los Angeles area in the early 2000s. The first concerns Tejon Ranch and the agreement passed in 2008 about Tejon Ranch between environmental associations and the owners : it poses the question of the meaning given to a preservation that would incorporate ecological, mythical and economic aspects of that territory, a remain of the Western past. The second deals with the decision that was made in 2007 by the City of Los Angeles to revitalize its river and offers a good example of the broadening of the definition of nature: it can also be urban. The ecological and cultural preoccupations about the river complicate the conservation problematic in Southern California. Finally, South Central Farm’s environmental justice case (1994-2006) is the sign of a transition in American environmental ideas from a clearly spatially limited object to a world issue