Row

Factor

Low sediments

1

Surface geology

・ stiff and compacted formations

・ dolomites

・ huge alluvial layers

2

Soils

・ containing high percentage of boulder

・ stiff textured clay

・ containing high organic substances

3

Weather

・ wet climate and rainfalls with low intensity

・ mostly snowfall

・ freezing and melting

・ dry climate

4

Runoff

・ low amount of maximum discharge in surface

・ low amount of runoff in surface

・ unique surface runoff

・ hydrologic soils of group A

5

The unpaved areas

・ Slow slope areas less than 5%

・ expanded alluvial plain

6

Limited plant coverage

Lots of sediments

・ ground coverage less than 40%

・ remarkable plant traces

・ dispersed trees

7

Land usage

・ the ground surface completely covered by plants, more than 70% traces of plant and boulders

・ low permeability of rain into erodible materials

8

High lands erosion

・ the absence of erosion signs

・ low erosion

9

River erosion and sediment transportation

・ wide and low deep with flat slope of streams

・ river bed on huge rock masses with boulders or with good plant coverage on the surfaces

・ controlled streams