1,720,998 research outputs found
Eredità complesse: delta urbanizzati tra acque, patrimoni e città
No full textPunto di partenza della ricerca di dottorato è l’osservazione dell’area metropolitana presso la foce del Tevere. Si tratta di un territorio disperso e destrutturato, con molteplici fronti d’acqua che lo rendono un paesaggio di transizione complessa, e al tempo stesso costellato di risorse culturali e naturali in cerca di un dialogo tra loro e con l’ambiente antropizzato. Coscienti che le risorse strategiche e il carattere in parte latente del territorio in esame risiedano nel particolare intreccio di “storia e natura”, si vuole raccogliere, partendo dal caso specifico, l’appello più generale ad integrare il patrimonio culturale e naturale nelle strategie di rigenerazione e conversione ecologica, in quanto elemento di sensibilizzazione, fonte di conoscenze e strumenti locali, e fattore di resilienza in grado di legare luoghi e persone, trasmettere valori identitari e stimolare la partecipazione. Si analizzano a tal fine alcuni casi selezionati nell’ambito europeo tra città metropolitane situate in contesti deltizi, costieri, irrigui e/o di bonifica, che abbiano quindi in comune con l’area di studio un paesaggio urbano caratterizzato da una transizione complessa tra terra e acqua: Stoccolma nell’arcipelago, Danzica nel delta della Vistola, e Lisbona nell’estuario del Tago. Obiettivo centrale delle analisi è mettere in luce i processi di patrimonializzazione sottesi alle trasformazioni urbane in corso e in che modo essi possano incidere su una auspicata ricomposizione del rapporto ambientale e culturale tra acqua e urbanizzazione.
L’obiettivo generale è quello di integrare delle strategie riferite ai patrimoni culturali e ambientali nella pianificazione territoriale al fine di fornire una efficace risposta alle problematiche del paesaggio d’acqua urbanizzato.
Nello specifico, la ricerca mira a:
_elaborare una lettura dell’area costiera romana in grado di evidenziare in modo integrato aspetti percettivi, valori storico-identitari, dinamiche di sviluppo di una rinnovata cultura idraulica;
_studiare approcci esistenti nella pratica contemporanea che integrino il patrimonio nella pianificazione e progettazione urbana come agente attivo nelle azioni di rigenerazione;
_a partire dalle lezioni apprese, formulare indicazioni strategiche per il territorio del delta del Tevere
Sustainability of groundwater management in the coastal plain of Dar es Salaam (Tanzania)
No full textThe city of Dar es Salaam (Tanzania) is one of the fastest‐growing cities in sub‐Saharan Africa. The city faces periodic water shortages, during which water demand is hardly satisfied. Only one third of the households receives water directly from the public water supply and water needs relies increasingly on groundwater. The sectors that represent the key/central aspects of vulnerability for Dar es Salaam, are water supply, waste management, drainage, and health services. The Adapting to Climate Change in Coastal Dar es Salaam (ACC-DAR) project is a co-founded research project, granted by the European Union, leaded by the Sapienza, University of Rome, in cooperation with Ardhi University of Dar es Salaam. The project will enhance the adaption to Climate Change (CC) capacities of Dar’s municipalities, by increasing their understanding of adaptation practices, and by developing methodologies for integrating adaptation activities into strategies and plans for Urban Development and Environment Management (UDEM) in unplanned and unserviced coastal settlements. This paper deals with the results obtained by the approach carried out in the aim of better manage groundwater in the coastal aquifer of Dar es Salaam
A groundwater modeling study aimed to the definition of managed aquifer recharge scenarios, in Dar Es Salaam coastal plain (Tanzania)
No full textThis paper presents the results of a modeling study on the potential effects of different scenarios of managed aquifer recharge in the Coastal Plain of Dar es Salaam (Tanzania). The city of Dar es Salaam is one of the fastest-growing cities in sub-Saharan Africa, with more than 4 million of inhabitants and a population growth rate of about 8 per cent per year. The city faces periodic water shortages, and in the last ten years, the excessive withdrawals of groundwater have accelerated the rate of seawater intrusion in the coastal plain. A steady-state groundwater model has been set up by the MODFLOW code, and calibrated by the UCODE code for inverse modeling. The purpose was to produce a reasonable accurate model of the groundwater flow system of the Dar es Salaam Coastal Plain, based on available data, and to simulate different scenarios of managed aquifer recharge, aimed to increase the amount of infiltration of precipitations in the subsoil
Groundwater management in Dar Es Salam coastal aquifer (Tanzania) under a difficult sustainable development
No full textThis paper deals with the approach and the consequent results referred to some activities carried
out in the framework of the Adapting to Climate Change in Coastal Dar Es Salaam (ACC-DAR) project, to
evaluate quantitative and qualitative evolution of groundwater in this coastal aquifer. The aim of the project
was to enhance the capacities of Dar’s municipalities to adapt to climate change (CC). In 2012 it was carried
out a monitoring campaign of groundwater, in order to evaluate CC effects and anthropic influences on
groundwater resources, and to highlight the critical aspects of groundwater management in the area that
could suggest consequent adapting measures. The data collected included precipitations, land cover and
chemical composition of groundwater. Field data were analyzed and compared with historical data of the last
ten years
Sensitivity of Dar Es Salaam coastal aquifer to climate change with regard to seawater intrusion and groundwater availability
Full text linkThis paper presents the initial results of three years of investigation activities, carried on in the Dar es Salaam coastal plain (Tanzania) by the Adapting to Climate Change in Coastal Dar es Salaam (ACC-DAR) project, a cofounded research project, granted by the European Union, led by the Sapienza, University of Rome, in cooperation with Ardhi University of Dar es Salaam. The ACC-DAR project activities will enhance the capacities of Dar’s municipalities by increasing their understanding of adaptation practices, and by developing methodologies for integrating adaptation activities into strategies and plans for Urban Development and Environment Management (UDEM) in unplanned and unserviced coastal settlements. In order to provide a series of enhanced methodologies for improving municipal activities related to climate change (CC) issues in the water management sector, the specific environmental phenomenon of seawater intrusion was investigated. This phenomenon is already contributing, and will increasingly contribute as CC progresses, to the degradation of those natural resources on which a large part of Dar es Salaam’s peri-urban livelihoods depends.
The target of this study was to investigate groundwater availability changes in Dar es Salaam’s coastal aquifer as a consequence of seawater intrusion and urbanization processes in the framework of CC effects, with the aim to set up an integrated approach to evaluate CC effects on groundwater resources in coastal plains affected by seawater intrusion, and to better manage these important natural resources. As such, geological and hydrogeological characterization of the area is part of the study, as lithological properties of outcropping geological formations and their main hydrogeological settings, as well as chemical groundwater characterization also depend on them, but they were not the target of the study
Numerical simulation of groundwater flow in Dar es Salaam Coastal Plain (Tanzania)
No full textThey are presented the results of a groundwater modeling study on the Coastal Aquifer of Dar es Salaam
(Tanzania). Dar es Salaam is one of the fastest-growing coastal cities in Sub-Saharan Africa, with with more than
4 million of inhabitants and a population growth rate of about 8 per cent per year. The city faces periodic water
shortages, due to the lack of an adequate water supply network. These two factors have determined, in the last ten
years, an increasing demand of groundwater exploitation, carried on by quite a number of private wells, which
have been drilled to satisfy human demand.
A steady-state three dimensional groundwater model has been set up by the MODFLOWcode, and calibrated with
the UCODE code for inverse modeling. The aim of the model was to carry out a characterization of groundwater
flow system in the Dar es Salaam Coastal Plain.
The inputs applied to the model included net recharge rate, calculated from time series of precipitation data
(1961-2012), estimations of average groundwater extraction, and estimations of groundwater recharge, coming
from zones, outside the area under study. Parametrization of the hydraulic conductivities was realized referring
to the main geological features of the study area, based on available literature data and information. Boundary
conditions were assigned based on hydrogeological boundaries. The conceptual model was defined in subsequent
steps, which added some hydrogeological features and excluded other ones. Calibration was performed with
UCODE 2014, using 76 measures of hydraulic head, taken in 2012 referred to the same season. Data were
weighted on the basis of the expected errors. Sensitivity analysis of data was performed during calibration, and
permitted to identify which parameters were possible to be estimated, and which data could support parameters
estimation. Calibration was evaluated based on statistical index, maps of error distribution and test of independence
of residuals. Further model analysis was performed after calibration, to test model performance under a range of
variations of input variables
Groundwater geochemical characterization in the karst aquifer feeding the Pertuso spring (Italy)
No full textThe present study deals with the geochemical characterization of Pertuso karst spring, the main perennial outlet of the karst aquifer in the Upper Valley of Aniene River, which is an important source for drinking water in the southeast part of Latium Region, in Central Italy. This paper deals with the supervisory monitoring plan related to the catchment project of the Pertuso spring which is going to be exploited to supply an important water network in the south part of Roma district. In order to identify the hydrogeochemical processes governing the evolution of groundwater and its circulation patterns, a multi-tracer approach was used to describe the hydrogeology of this karst system with the aim of achieving proper management and protection of this important resource due catchment works. To investigate the evolution of groundwater compositions, groundwater from different parts of the aquifer was sampled. Groundwater samples were collected from Pertuso karst spring and from four monitoring wells between July 2014 and January 2015 and analysed for major and trace elements. Physico-chemical parameters (e.g., temperature, pH, Eh, EC etc.) were also measured. A detailed analysis provides that all of groundwater samples have the same origin, associated lithologies, and mineral-solution reactions related to hydrodynamic responses. Piper diagram reveals higher bicarbonate and calcium suggests interactions with carbonate rocks, yielding increased Ca concentrations in the groundwater. Groundwater are characterized by low mineralization and low Mg/Ca ratios and represents the flux of rapid infiltration of surface waters through sinkholes and well-developed karst conduits network. Results from geochemical interpretation of groundwater chemistry using PHREEQC and the measured pH and Eh of groundwater sampled indicate that most of the samples were saturated with respect to calcite and aragonite, however all sampled waters were undersaturated with respect to dolomite and gypsum. Geochemical modelling showed that spring water and groundwater are made of surface water, providing quantitative information on the vulnerability of groundwater to potential surface water contamination
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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