Search results for " ephemeral gully"
showing 9 items of 9 documents
Rilievo di un ephemeral gully nell’area sperimentale di Sparacia mediante una tecnica fotografica
2016
Nella memoria sono riportati i risultati dell’applicazione di una tecnica imagebased per il monitoraggio di un ephemeral gully formatosi nel gennaio 2015 nell’area sperimentale di Sparacia. Nel gully, lungo 54 m, sono state individuate 24 sezioni trasversali che sono state rilevate in campo mediante l’uso di un profilometro. L’indagine ha inoltre previsto la realizzazione di un modello tridimensionale del terreno (DTM) ottenuto con l’impiego di un numero elevato di fotografie della stessa scena acquisite da differenti punti di vista (Tecnica “Structure-From Motion” SFM e “Multi-View-Stereo MVS). Dal DTM tridimensionale (3D) e dal modello 2.5D sono stati estratti i profili delle sezioni tras…
Similitudine nelle caratteristiche morfologiche dei rill e degli ephemeral gully
2008
Modeling Rill Erosion at the Sparacia Experimental Area
2015
In this paper the contributions of rill and interrill components to total soil erosion monitored at event scale at the Sparacia experimental area, Southern Italy, were firstly compared and the dominance of the rill component was detected. Then, the reliability of two empirical relationships between the rill length and its eroded volume and among the morphological variables (length, width, depth and volume) describing the channelized process was tested using both direct measurements of rills, carried out for the October 3, 2011 event, and those of ephemeral gullies surveyed on February 2010 at Sparacia. The measurements of rills detected by the direct field relief were compared with those ob…
Field investigation of rill and ephemeral gully erosion in the Sparacia experimental area, South Italy
2013
Abstract This paper reports the results of a field investigation aiming at characterizing the morphology and hydraulics of both rills and ephemeral gullies (EGs) monitored at Sparacia experimental area, Sicily, Italy. The comparison between rill and interrill erosion measurements showed that sediment delivery processes occurred in some erosive events and that the rill erosion rate was dominant in many cases. The measurements were used for testing both the empirical relationships between the channel (rill, EGs and gully) length and its eroded volume and among the morphological variables (length, width, depth and volume) describing the channelized process. Finally, the rill and EGs hydraulic …
Similarity between morphological characteristics of rills and ephemeral gullies in Sicily, Italy
2009
This paper reports the results of a field investigation aimed to establish morphological similarity between rills and ephemeral gullies. Rill measurements were made on 14 plots having a surface area of 22–352 m2 located on a 14·9% slope and on a plot 6·0 m wide and 22·0 m long having a uniform 22·0% slope. The plots are located on the experimental station for soil erosion measurements, ‘Sparacia’, of the Agricultural Faculty of Palermo University, in Sicily, Italy. All plots are subjected to natural rainfall. The measurements were made immediately following five events between November 2004 and December 2005. The ephemeral gully measurements were made on a cultivated area of about 120 ha, l…
Testing the use of an image-based technique to measure gully erosion at Sparacia experimental area
2017
The first part of this investigation was aimed at testing the use of a three‐dimensional (3D) digital terrain model and a quasi‐tridimensional (2.5D) digital elevation model obtained by a large series of oblique images of eroded channels taken from consumer un‐calibrated and non‐metric cameras. For two closed earth channels having a different sinuosity, the ground measurement of some cross sections by a profilometer (P) was carried out and their real volume was also measured. The comparison among the three methods (3D, 2.5D, and P) pointed out that a limited underestimation of the total volume always occurs and that the 3D method is characterized by the minimum difference between measured a…