Impact Factor (IF) - Thomson Reuters Web of KnowledgeSM)

2016: 0.938 - 5 years IF: 1.010

2015: 0.641 - 5 years IF: 0.673

2014: 0.628 - 5 years IF: 0.652

2013: 0.390 - 5 years IF: 0.504

2012: 0.605

2011: 0.468

2010: 0.309

2009: 0.136

An international Journal published under the auspices of:

Recognized by:

Volume 4 (1) - 1981

BIANCOTTI A.

Morfologia, suoli ed erosione in Valle Marchiazza (Biellese) – Morphology, erosion and soil types in Marchiazza Valley (District of Biella, Piedmont, Italy)

Pages 30-38

Abstract

The hydrographic network of this basin is given by water courses showing in their talwegs two steps, close each other, yielded by two different stages of regressive erosion. In both hillsides, 4 or 5 terrace levels may easily be recognized: the upper one is likely dued to Riss Glaciation, the following to Wurm, whereas the two lowest, related to river-bed’s steps, have neotectonic origin. In his lower part, the basin shows a typical « Richter’s hillside shape», given by a slightly concave base (equilibrium slope of transport and light ablation). Soil types may be grouped in a few associations, in which are prevailing lithic Udorthents, typic Dystrochrepts and slightly leached Dystyc Eutrochrepts. Regression forms dued to rejuvenation, or directly rock outcroppings, occur when erosion is pretty active. Slope deposits give rise to typic Udifluvents or colluvial soils. Ablation occurs in hillsides because of a widespread surface water-creeping, whereas solifluction phenomena are pretty lacking. Max-erosion moment clashes with a period of short and heavy rainfalls, so that the sheer power of waterstreams, at top of basins, may erode thoroughly detritic materials coming from hillsides. By the other hand, alluvium occurs when talweg slope decreases. Far downstream a charge decrement fosters un increase of net power which causes erosion in river-beds and outcropping of bedrocks, aided in this by regressive erosion in progress. Soil chains occurring in slopes confirm the suggested erosion model.

→ Download Abstract PDF

Contribute to CGI downloading this Volume:

€5.00

Or choose an annual subscription - Go to subscriptions page