Search results for " Topografia"
showing 10 items of 398 documents
Surface soil water content estimation based on thermal inertia and Bayesian smoothing
2014
Soil water content plays a critical role in agro-hydrology since it regulates the rainfall partition between surface runoff and infiltration and, the energy partition between sensible and latent heat fluxes. Current thermal inertia models characterize the spatial and temporal variability of water content by assuming a sinusoidal behavior of the land surface temperature between subsequent acquisitions. Such behavior implicitly supposes clear sky during the whole interval between the thermal acquisitions; but, since this assumption is not necessarily verified even if sky is clear at the exact epoch of acquisition, , the accuracy of the model may be questioned due to spatial and temporal varia…
LA VIABILITÀ MINORE NELLA SICILIA CENTRO-MERIDIONALE: IL COMPRENSORIO DI CIGNANA TRA LA VIA SELINUNTINA E LA CATINA-AGRIGENTUM
2021
Obiettivo del contributo è esaminare il sistema stradale di età antica, con un’attenzione particolare rivolta alle vie secondarie, in un ben definito comprensorio della Sicilia meridionale, l’area del Progetto Cignana, pochi km ad est di Agrigento. Si tratta di cogliere non tanto i caratteri della viabilità di lunga percorrenza (la via Selinuntina e la via Catina-Agrigentum) quanto piuttosto le interconnessioni tra i principali assi viari, la rete secondaria (spesso attestata lungo i principali corsi d’acqua), gli insediamenti rurali e gli approdi sulla costa. This paper is aimed to analyze the ancient road system in a selected area of the Southern Sicily, between Agrigento and Licata (Cign…
Mapping evapotranspiration on vineyards: The Sentinel-2 potentiality
2012
stimation of actual evapotranspiration in Sicilian vineyards, is an emerging issue since these agricultural systems. Indeed unlike other agricultural species (Vitis vinifera L. ) are generally cultivated under mild water stress, in order to enhance quality (Guadillère et al. , 2002. This has significant impacts on the management of the scarce water resources of the region. The choice of the most appropriate methodology for assessing water use in these systems is still an issue of debating, due to the complexity of canopy and root systems and for their high spatial fragmentation. In vineyards, quality and quantity of the final product are dependent on the controlled stress conditions to be s…
Proximal-sensing-powered modelling of energy-water fluxes in a vineyard: A spatial resolution analysis
2021
Spatial resolution is a key parameter in energy–water surface flux modelling. In this research, scale effects are analyzed on fluxes modelled with the FEST-EWB model, by upscaling both its inputs and outputs separately. The main questions are: (a) if high-resolution remote sensing images are necessary to accurately model a heterogeneous area; and (b) whether and to what extent low-resolution modelling provides worse/better results than the upscaled results of high-resolution modelling. The study area is an experimental vineyard field where proximal sensing images were obtained by an airborne platform and verification fluxes were measured via a flux tower. Modelled fluxes are in line with th…
Assessing daily actual evapotranspiration through energy balance: an experiment to evaluate the selfpreservation hypothesis with acquisition time
2013
An operational use of the actual evapotranspiration estimates requires the integration from instantaneous to daily values. This can commonly be achieved under the hypothesis of daytime self-preservation of the evaporative fraction. In this study, it has been evaluated the effect of this assumption on the assessment of daily evapotranspiration from proximity sensing images acquired at hourly intervals over a homogeneous olive groove. Results have been validated by comparison with observations made by a micrometeorological (EC-flux tower) and an eco-physiological (sap flux) sensor. SEBAL model has been applied to thermal and multispectral images acquired during a clear day on August 2009 trou…
Il monitoraggio topografico della cattedrale di Agrigento con metodi tradizionali
2014
L’oggetto del presente lavoro è il monitoraggio della cattedrale di San Gerlando di Agrigento, duomo eretto tra i secoli XI e XII, che sorge nella parte più alta della collina di Girgenti. Lo studio è significativo poiché, nel corso dei secoli la costruzione è stata soggetta a interventi di ristrutturazione e di consolidamento, resi necessari dai danni arrecati da frane che, in più occasioni, hanno coinvolto il territorio su cui essa sorge. Dal 2010 la chiesa è chiusa al culto per copiosi eventi franosi e idrogeologici che hanno allarmato ulteriormente anche la Protezione Civile. A seguito di questi eventi è stata avviata una campagna di indagini e monitoraggi con il fine della caratterizza…
Nicola Bonacasa. L'università di Palermo e il territorio
2016
Nel lavoro si ripercorre l'impegno di Nicola Bonacasa nei rapporti tra Istituto di Archeologia di Palermo e il territorio nei tre aspetti fondamentali di promozione delle ricerche, rapporti con la Soprintendenza di Palermo nella tutela e salvaguardia dei siti archeologici e impegno nell'attività di consulenza nei confronti dell'Assessorato regionale dei Beni Culturali.
Rilievo integrato presso il Borgo Schirò (PA)
2013
Il lavoro qui presentato consiste in un rilievo integrato (Topografico/GPS statico/NRTK/Laser Scanner) di un piccolo contesto extraurbano siciliano, Borgo Schirò, noto per le vicende storiche che portarono alla sua costruzione a seguito dell’emanazione della legge n.1 del 2 gennaio 1940, per il superamento del latifondo. Data la natura varia degli elementi da rilevare (edifici, arredo urbano, strade) sono state adottate tecniche di acquisizione diversificate per ognuno di essi, le quali, in forma integrata, hanno permesso un utile confronto finale degli elaborati prodotti, offrendo la possibilità di effettuare analisi qualitative altamente accurate su singoli casi strutturali ed elevati gra…
Coupling SAR X-band and optical data for NDVI retrieval: model calibration and validation on two test areas
2013
Sustainability of modern agro-hydrology requires the knowledge of spatial and temporal variability of vegetation biomass to optimize management of land and water resources. Diversely from optical imaging, temporal resolution of active sensors, such as SAR, is not limited by sky cloudiness; thus, they may be combined with optical imageries to provide a more continuous monitoring of land surfaces. Several new SAR missions (e.g., ALOS-PALSAR, COSMO-SkyMed 1 and 2, TerraSAR-X, TerraSAR-X2, Sentinel 1) acquiring at X-, C- and L-bands and dual polarization capability, are characterized by a short revisit time (from 12 h to ~10 days) and high spatial resolution (<20 m). These satellites could prov…
Vegetation index retrieval by coupling optical and SAR images
2012
Monitoring spatial and temporal variability of Vegetation Indices (VIs) is important to manage land and water resources, with significant impact on the sustainability of modern agriculture Although algorithms based on optical data give accurate products, cloud cover dramatically reduces the temporal resolution of these outputs. The launch of new Synthetic Aperture Radar (SAR) constellations such as COSMO-Skymed opened new opportunities to develop agro-hydrological applications. Indeed, these satellites may represent a suitable source of data for operational applications due to their high spatial and temporal resolutions (10 m in StripMap PingPong acquisition mode, best revisit time with 4 s…