In the analysis of high gradient mountain streams an important aspect is represented by the quantification of the bedload transport. Field data necessary to test transport models and better understand sediment transport phenomena result scarce and difficult to obtain. In the present study, we focus the attention on the results obtained by multiple field surveys carried out after the November 2012 event when bedload transport along the Rio Cordon, a small step-pool channel in the eastern Italian Alps, was generated. The stream is characterized by the presence of a station, managed by the Regional Land Safety Department of ARPAV (Regional Agency for Environmental Protection and Prevention of Veneto), for monitoring water and sediment fluxes since 1986. The measuring station consists of an inclined frame that separates fine from coarse sediments (D>20 mm), which are continuously assessed by a series of ultrasonic sensors fitted above a storage area. After the November 2012 event, a series of field surveys were carried out to identify the source area of the mobilized sediment. The quantification of bedload and fine loads using a Terrestrial Laser Scanner device was then performed, allowing the definition of the volume and grain-size characteristics of the transported sediment. The results have shown that the main source area was represented by lateral small debris flow located just upstream the measuring station. Thanks to the grain-size characterization and the field recognition it was possible to confirm that no morphological changes of the main channel have occurred upstream the sediment sources immission. Therefore, the input of sediment for the stream derives only from lateral debris flow process located near to the catchment output.

Monitoring and analysis of the sediment transport event of November 2012 in the Rio Cordon station.

RAINATO, RICCARDO;PICCO, LORENZO;LENZI, MARIO ARISTIDE;MAO, LUCA;DELAI, FABIO;RIGON, EMANUEL;MORETTO, JOHNNY;CESCA, MATTEO;VIANELLO, ALESSANDRO;
2014

Abstract

In the analysis of high gradient mountain streams an important aspect is represented by the quantification of the bedload transport. Field data necessary to test transport models and better understand sediment transport phenomena result scarce and difficult to obtain. In the present study, we focus the attention on the results obtained by multiple field surveys carried out after the November 2012 event when bedload transport along the Rio Cordon, a small step-pool channel in the eastern Italian Alps, was generated. The stream is characterized by the presence of a station, managed by the Regional Land Safety Department of ARPAV (Regional Agency for Environmental Protection and Prevention of Veneto), for monitoring water and sediment fluxes since 1986. The measuring station consists of an inclined frame that separates fine from coarse sediments (D>20 mm), which are continuously assessed by a series of ultrasonic sensors fitted above a storage area. After the November 2012 event, a series of field surveys were carried out to identify the source area of the mobilized sediment. The quantification of bedload and fine loads using a Terrestrial Laser Scanner device was then performed, allowing the definition of the volume and grain-size characteristics of the transported sediment. The results have shown that the main source area was represented by lateral small debris flow located just upstream the measuring station. Thanks to the grain-size characterization and the field recognition it was possible to confirm that no morphological changes of the main channel have occurred upstream the sediment sources immission. Therefore, the input of sediment for the stream derives only from lateral debris flow process located near to the catchment output.
2014
Quaderni di Idronomia Montana, 31
9788897181293
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11577/2741079
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact