Lulc_veg parameter in annual water yield model

Science & Research
#1

I’m using the CCI land cover dataset with some InVEST annual water yield runs. To set up the table, we need a LULC_veg parameter in the table for each land cover class. The user guide says “Values must be 1 for vegetated land use except wetlands, and 0 for all other land uses, including wetlands, urban, water bodies, etc.”

This is great, but what about the case of “sparse vegetation” (<15% cover) - would that still be considered vegetated? What about lichen or moss cover? My assumption is to code sparse vegetation as 1 and lichen/moss as 0. What are your thoughts?

#2

Hi @kjbagstad, I’m sorry I don’t have any specific recommendations for this case (and it is an interesting one), but I’ll ping a few folks about it. That being said, the LULC_veg parameter determines which AET equation is used for this landcover, so if there is an AET equation that would make the most sense for your sparse vegetation case, perhaps that would drive the decision one way or another? The two equations are labeled 1 and 2 in https://invest-userguide.readthedocs.io/en/latest/reservoirhydropowerproduction.html for your reference.

Hope this helps!
James

#3

Hi Ken, I’ll chime in here by agreeing with your assumption that sparse veg is assigned 1 and lichen/moss as 0. Really, I’m fascinated that you’re working somewhere with an actual land cover class of lichen/moss and want to visit it! Since the latter don’t put roots into the soil, they aren’t subject to the rooting depth portion of the model. And assuming that there is actually some veg in the sparsely vegetation area, those do contribute to soil moisture conditions, however minor.

~ Stacie

#4

Makes sense, thanks @swolny!