In running SLAMM with somewhat customized wetland categories (for the Hudson River), we are seeing a progression where cells don't convert to a couple of our categories (tidal swamp and vegetated tidal flat). We are thinking this could be because of elevation range overlap that each of these categories have with other categories. Does this make sense? Any other possible reasons?
Wetland succession under SLR is entirely driven by the SLAMM decision tree (page 40 of the SLAMM 6.2 tech doc, and then more detail in the category-by-category description of wetland fate that follows...)
Vegetated tidal flat is a rarely-used category and, unless salinity is modeled and specific salinity rules are set up, SLAMM has no way of predicting whether a flat would have vegetation or not. Therefore it will never be produced by SLAMM.
Tidal swamp will not be produced unless salinity is being explicitly modeled or if a polygon is designated as a "freshwater influenced" zone in which dry lands or non-tidal swamps would convert to tidal swamps if inundated.
The rigidity of the SLAMM decision tree is something that we plan on addressing in future years to assist in site-specific modeling that doesn't fit in with the primary conceptual model.
Best regards -- Jonathan
Thanks Jonathan, this is very helpful. We are still trying to figure out the best way to make SLAMM work in the Hudson Estuary.