[DOCUMENTATION] Mean Annual soil Erosion rate

[SethCallewaert]

Documentation references: https://github.com/cn-ws/cn-ws/blame/master/docs/watem-sedem.rst#L73 (and on the whole page)

Please use either use option A) or B) and fill in the selected options:

B. I have a question considering this section:

In the text there is often referred to the mean annual soil erosion rate, however I feel like RUSLE give a total/potential/maximal/calculated erosion rate per pixel. So it is not clear to me if here the pixel values are referred to or the mean value of all the calculated pixels.

I would rather choose a less ambiguous name for the annual erosion rate (I feel like within our other studies we mostly use potential soil erosion).

To nitpick even harder I would like to propose the letter A for the annual soil erosion instead of E (conform to most literature), and then E could for example be used for Net erosion (see https://github.com/cn-ws/cn-ws/issues/55)

[daarende]

@Sachagobeyn Change symbol E to A for anual soil loss, check if it does not overlap with any other symbol referred to in the docs.

[Sachagobeyn]

In the text there is often referred to the mean annual soil erosion rate, however I feel like RUSLE give a total/potential/maximal/calculated erosion rate per pixel. So it is not clear to me if here the pixel values are referred to or the mean value of all the calculated pixels.

Good point. I'm not sure if we can translate RUSLE to total/potential/maximal/calculated erosion rate per pixel as RUSLE is a theoretical concept, outside the raster/pixel context of CN-WS. Looking at Renard et al. (1997):

and

we should define RUSLE as A and as mean annual soil erosion rate. E should be defined as:

Erosion, or net erosion as you stated.

In summary, @SethCallewaert , ok?:

• A: mean annual soil erosion rate- theoretical gross erosion concept.
• E: netto erosion - theoretical net erosion concept.
• Symbols: A and E are not mentioned/referred in case we talk about model applications (raster/pixel)

Ref: Renard, K.G., Foster, G.R., Weesies, G.A., McCool, D.K., Yoder, D.C., 1997. Predicting soil erosion by water: a guide to conservation planning with the revised universal soil loss equation (RUSLE), Agriculture Handbook. U.S. Department of Agriculture, Washington.

[petradeproost]

A is indeed the most common symbol for average annual soil loss. On the contrary, I am not so sure that E is the common symbol for net erosion. But I suppose we can define it as net erosion.