buttonThere are 10 types of land use: cropland, forest, pasture, shrub, grassland, wetland, impervious, barren, water, snow. How should the appropriate C and P values for global-scale SDR operation be selected?
I hope to obtain appropriate values for processing.
Welcome to the forum @Xionghailing -
First, it would be useful to know how you or someone else would be using the global scale model results. At a global scale you are going to be making one set of huge assumptions no matter which values you choose for C and P. I would suggest that the most important thing is to make sure that the relative values for C between land use classes seem correct in general. For example, agriculture might generally have higher erosion, pasture less erosion than agriculture, forest much less, and perhaps impervious the least.
For P, we would usually set that value to 1 for all classes, unless you’re interested in understanding, for example, what happens if all agriculture everywhere in the world was to adopt some particular sediment-reducing practice like cover cropping.
For C, you could use some of the general sources referred to in the Data Sources section of the User Guide, which can help with the relative values. I also recommend looking into other global studies that have been done with SDR and see how they parameterized it, such as Chaplin-Kramer et al 2023, Mapping the planet’s critical natural assets. For other global studies, you can search our publications database.
~ Stacie