[RFC] Feature Proposal - landcover proposal V2

[Minh_Nguyen (Minh Nguyễn)]

@Cartographer10

We removed landcover=water from the proposal. It became clear that to many people reject this value.

Bummer, I was really looking forward to mapping landuse=reservoir areas coincident to landcover=water areas, to clarify that the reservoir is covered by water.

@Map_HeRo

When I started mapping with OSM one of the first problems I encountered was the mixup of landuse (utilization) and landcover (physical coverage) all under the landuse key and as a result out of this mixup the use of 2 or 3 different landuses overlapping each other in certain places. It does not make sense to me and it does not to several other mappers, as you can easily see in view of lots of discussions adressing this issue again and again.

From that point of view a proposal with the target to provide better and more clear definitions of landuse and landcover for OSM use in accordance with the definitions of these terms in real life sound like a big improvement to me (and will definitely get my full support).

What I most appreciate about this discussion is the awareness that land use is orthogonal to land cover. I regularly encounter confusion on this point not only among new mappers but also among experienced mappers who, for instance, argue for cutting a hole in a landuse=residential area to accommodate a lush landuse=grass in someone’s front yard, or for cutting up the landuse=residential area into tiny chunks criss-crossed by yet-to-be-mapped landuse=highway and area:highway areas, or fractalizing a landuse=residential to exclude parts of residential buildings merely because of some overgrown trees. Confounding matters are the non-landuse tags like amenity=hospital and leisure=park.

The proposal strikes me as something that would’ve been pretty reasonable at the outset of the OSM project (well before my time). If the community had agreed to distinguish between landuse and landcover in raw tags upfront, there would’ve been less of this confusion. Here in the 2020s, it should be possible to educate mappers without as much disruption by clearly distinguishing between landuse for land use and landuse for land cover when organizing presets in an editor UI or organizing wiki articles in a category. iD does this to some extent, putting some land cover presets under “Natural Features”. However, we would have to trust data consumers to be aware of the LU/LC distinction regardless of an explicit distinction in key names.

@Tjuro

This is not a requirement to start mapping these “Must contain” landcovers. but is important to understand possible rendering methods for landuse and landcover. That is why the whole part is under the “Rendering” part of the proposal.

Perhaps the column would be less confusing with a name like “Normally contains”.

There’s something to be said for delineating land use and land cover based on what can and can’t overlap. However, it seems inevitable that there will be some gray area, because large properties often contain a hierarchy of uses. For example:

• This horse farm contains several pastures for grazing, which up to now have needed to be tagged as landuse=meadow.
• This local park contains a golf course, athletic fields, a campground, and a heritage farm.
• This cemetery doubles as an arboretum (which is by definition tree-covered) and contains a nature preserve.

I realize this proposal is primarily about land cover. However, I hope it doesn’t promote the idea that we can eliminate overlapping land use areas too.