Localizing InVEST - adding site specific data

Hi - in order to supplement use of large (coarse) datasets, is there a way of inputting data obtained directly from filed data collection.
For instance, I wish to set up an ES analysis for a small forest park c. 25 acres. I have collected soil samples (and obtained data for Total C, N, bulk density, macroporosity as well as eDNA sampling for soil biota). I would like to add this information to nationally available raster-based data in order to give me more site specific ES performance information.
Many thanks
Richard

Hi @Minton71 -

In general, it is fine to use either coarser datasets or field data in InVEST (or to mix coarse and fine data within a model run), as long as they are formatted correctly, have the correct units, etc, as described in the User Guide.

As for combining coarser data with field data within the same dataset, that’s also fine to do, you’ll just need to do some GIS work to combine them. For a recent project using the Coastal Vulnerability model, we had finer data for habitats within only part of our study area, so I combined these fine data with coarser national datasets to create the layers used in the model.

You’ll also want to pay attention to the resolution that the model outputs will have, so it might be best to resample your coarse inputs to have the resolution of your field data (if the field data is higher-resolution). And if you’re combining coarse and field within the same dataset, you’ll want to use the highest resolution of all of your inputs for creating the layer, so you don’t lose field data detail.

~ Stacie

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Hi Stacie, thanks for your message and sorry I didn’t reply earlier.
I have a related follow-up query that possibly doesn’t warrant a new topic.
My particular focus of ES assessment is comparing alternative agriculture LULC to ‘conventional’ farming. I am hoping to create new LULC classifications that accurately reflect the provisioning and regulating ES performance of various farming practices and land covers. So apart from digitising fine grain polygons (the point of my previous query( i also need to provide attributes to each LULC type the represent the classifications’s inherent ecological values). However, I have looked through 4 InVEST models relevant to agricultural land (C storage / Crop Production / SDR / Seasonal Water Yield) and I see only two of these (SDR and water yield) feature Biophysical Tables with which to scientifically parameterise LULC.
Do you have any suggestions how we could incorporate additional parameters (rooting depth, plant available water, soil water holding capacity, fertility etc.) to inform specialised LULC?
Look forward to any suggestions you might have.

Kind regards
Richard

Hi Richard -

The Carbon Storage model also has a biophysical table, where you provide 4 carbon pool values for each land cover type. This model is entirely driven by the LULC and this mapping to carbon pools. It’s possible that the soil carbon pool might be most impacted by different agriculture practices.

I’ve never used the Crop Production model, but it looks like you can customize different fertilizer applications for different crop types. This might be the only variable that can be user-specified.

Rooting depth and available water content are used for the Annual Water Yield model, not Seasonal, but Seasonal Water Yield (SWY) includes crop coefficient Kc which is relevant. In general, if you want to specify some characteristic of different LULC types that isn’t included in the model, the way to do it is to create more LULC classes that are differentiated by that characteristic, as you’ve noted. The thing is, while this is useful for being able to provide different model-specific LULC parameters for different agriculture types, it does not cause the model to, for example, make use of rooting depth information in its calculations if they are not part of the model design.

The biophysical table really is the main place where we specify LULC-specific parameters. If you think that the practices will significantly impact soil properties over the long term, then you could make those changes to the Kfactor (erodibility) in SDR or hydrologic soil group (SWY), but I’ve never done that, so don’t have any advice there.

~ Stacie