Forest Carbon Edge Effect theta parameters

Hi I am a student which is learning InVEST model.
When I was using “Forest Carbon Edge Effect” model there has some few question
How to creat a “Global Regression Models” in shp.?
I have read the InVEST documentation and know how is the model work. But when I run the model ,it always tell me " Expected the field “method” but did not find it".
Can someone provide a reference to a successful operation case?



Hi @hongkongdoll and welcome to the forum!

In general, when you get an error running the model, it is useful if you post the entire log file (.txt) that the model produces in your Workspace. It gives us more information to work with.

In this case, it might be helpful to review what the User Guide says about this input parameter:

…Default data is provided. Required if Compute Forest Edge Effects is selected.
This input is provided in the sample data and need not be altered unless you have run a separate regression for your region and have better or updated information. …

And in the How it Works section:
“The results of these regressions can be found in the carbon edge regression parameter shapefile (core_data/forest_carbon_edge_regression_model_parameters.shp) in the sample dataset that is provided for the InVEST carbon edge effect model.”

So you’ll need to download the InVEST sample data for this model, which you can do through the Workbench user interface if you’re using it, or at install time if you’re using the “classic” version, or by clicking on the Individual Sample Datasets link on the InVEST web page.

~ Stacie

Thanks sir @swolny
I have done the model using sample data
next question is when I using “forest_carbon_edge_regression_model_parameters.shp” which in sample model data to calculate my map. I have got a result but I don’t know whether is correct or not because the log file show me there is something wrong.
I upload my log file.
InVEST-natcap.invest.forest_carbon_edge_effect-log-2022-09-20–08_59_05.txt (9.0 KB)



Hi @hongkongdoll -

Thanks for uploading your log file. It looks like the main error is Point outside of projection domain. While this is not a very helpful message, my guess is that it means that your area of interest lies outside of the area that has regression information. If you are actually working in Taipei, the whole island of Taiwan is not covered by the regression model data. To check this, bring the sample data shapefile forest_carbon_edge_regression_model_parameters.shp into the GIS and see if it overlaps with your area of interest. If not, then you will not be able to use this model to compute edge effects.

~ Stacie

Thanks for reply @swolny
I have chacked the area, you’re right. The sample data shapefile is not cover my area(which is taipei).
So how to create a parameters.shp that can cover my area?
Or if somewhere can download data?



Hi Chauncy -

The only thing I know about the science behind the model is what’s in the User Guide, which says “This model follows the methodology described in Chaplin-Kramer et al. (2015), which constructs a series of regression models between forest biomass density (Mg/ha) and distance from forest edge (km) for 100 km x 100 km grid cells throughout the pantropics.” All of the regression data that they generated is included in the sample data, so there is no additional prepared data available for download.

If you want to use their methodology to create similar data for your area, go for it. Unfortunately, this is not something that most of us at NatCap have done, so we probably won’t be able to help with the process.

~ Stacie

Thanks sir @swolny
I’ll find some way to solve it.
Thanks again for taking the time to answer my doubts.