I would like to ask why I use the Water Production module, which calculates that the water yield of the last water area is 0

Software Support
1

I would like to ask why I use the Water Production module, which calculates that the water yield of the last water area is 0
InVEST-natcap.invest.annual_water_yield-log-2024-05-06–16_21_40.txt (21.1 KB)

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Hello @b-2654556941, and welcome!

Am I understanding correctly that the Annual Water Yield model is producing water yield values of 0 for places where the land use/land cover map is “water”?

For trying to understand any model output, first see how it corresponds with the input data. If it is specifically water areas that you’re concerned about, look at the values in the biophysical table that correspond with the “water” land use/land cover class. And look at the model equations to understand how those values affect the results.

If this doesn’t explain the 0 values, please provide more information about what you’ve tried, and the input values that you are using.

~ Stacie

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Thanks for your reply!After reviewing the information, I found that the evapotranspiration in the study area is indeed much greater than the precipitation,and my study area is mostly water，so the result is largely 0 ,how can I solve this problem.

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If you feel that this result is incorrect, then I see two main options:

1/ Look for different precipitation and evapotranspiration data that seems more accurate.

2/ Maybe this model is not appropriate for your study area. It is very simple, and makes a lot of assumptions about non-vegetated land cover types like water. If you know that the area produces a lot of water yield, it is possible that the water is coming through baseflow, or groundwater recharge, which are not explicitly included in this model.

~ Stacie