On Wednesday 30 September 2015, joost schouppe wrote: > I don't think a landuse tag is sensible, as the salt flats I have in > mind (look up some images of Salar de Uyuni to get an impression) are > definitely not something human centered. However, it might be a good > tag for some of the smaller areas where salt is actually harvested.
The Salar de Uyuni is somewhat special since there is permanent water (brine) below the salt crust across large parts of it and partial water cover above the salt during wet season. natural=water for the whole area seems wrong here. > I don't see how the natural=desert would be wrong because of the > outline not coinciding with the deserts' end. In fact, you could > argue that the desert does end at the salt's edge; there is a very > sudden shift in vegetation and barren-ness there. The "islands" > within it are really like oasis in the desert. But even if the > argument does hold, why couldn't there be a natural=desert / > desert=salt surrounded by natural=desert /desert=sand ? Depending on definition a desert is either defined by aridity (lack of water) or lack of vegetation. Neither of these generally applies to a dry lake area and not to the immediate area around as well. But it does not really matter since deserts can be considered non-verifiable and not mappable within the scope of OSM anyway. In general it is probably best to think of it in terms of what characterizes what you would like to map. There are: - the hydrological aspect - the presence of standing water or water saturated ground - the topographic aspect - the presence of a very flat area - the physical aspect - the presence of soluble salts and non-soluble young fine grained sediments at the surface - the geomorphological aspect - the mechanism that formed the area in question, i.e. deposits left by local evaporation of water Depending on what aspect is key for you different tags make sense and it might be a good idea to choose tags that refer to indivisual aspects rather than a combination of all of them (which is what natural=salt_flat would imply). -- Christoph Hormann http://www.imagico.de/ _______________________________________________ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
