SDR, interpretation of results

[gabialbardella]

Hello

I have a question regarding the interpretation of final data.
In InVEST User Guide it says:
avoided_erosion.tif (type: raster; units: tons/pixel/year): The contribution of vegetation to keeping soil from eroding from each pixel. (Eq. (83))

avoided_export.tif (type: raster; units: tons/pixel/year): The contribution of vegetation to keeping erosion from entering a stream. This combines local/on-pixel sediment retention with trapping of erosion from upslope of the pixel. (Eq. (84))

So in the following results:

Higher values indicate less erosion, due to the contribution of vegetation, the larger the value, does vegetation prevent or retain sediments?

Thank you very much for everything

[jdouglass]

The pixel values for these two outputs are calculated very differently, so they have different meanings.

For avoided_erosion.tif, values indicate the amount of erosion from that pixel that is avoided because of the vegetation on that pixel. Higher values indicate more erosion prevented from happening due to vegetation.

For avoided_export.tif, values indicate the amount of erosion from that pixel as well as trapping of sediment that originated upslope of that pixel so that neither enters a stream. You could think of this as total sediment retained on the pixel. Higher values indicate more sediment retained by the vegetation on that pixel, including from upslope pixels.

Hope this helps and let us know if you have any further questions,
James

[gabialbardella]

Thank you very much, your explanation helped me better interpret the results, I hope you have a good day.

[Elly]

If you want to understand more you can even go far and look at which LULC change classes has more contribution to avoided_erosion in your watershed. All the best

[gabialbardella]

@Elly Thank youu, I will look into it, in order to complement and relate the information.