There is a "wetland" proposal which includes wetland=mangrove. http://wiki.openstreetmap.org/index.php/Proposed_features/Wetland_areas
In the area where I am working at the moment http://www.openstreetmap.org/?lat=-0.85&lon=-46.991&zoom=9&layers=0B0FTF (almost) all the coastline is drawn along the outer border of mangrove forests, so it is considered as "land". I tagged mangroves at http://www.openstreetmap.org/?lat=-0.8964&lon=-46.6742&zoom=12&layers=0B0FTF as natural=wetland tentatively ... I would like to see the wetland tag voted/approved/rendered -- it could help to map a not-so-small part of tropical coastlines correctly! BTW, there is a mangrove island in this area rendered correctly in Osmarender but not in Mapnik, in spite of a multipolygon relation which is correct in my opinion: http://www.openstreetmap.org/?lat=-0.95206&lon=-46.66697&zoom=15&layers=0B0FTF Ulf On Wed, 2008-07-09 at 22:21 +0100, Mark Williams wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > natural=marsh? > (from Map Features) > > I would expect to find coastline on the open-sea border of this. > > Mark > > Mike Collinson wrote: > > I agree with Stephen's comments and add that I follow the rule "if in > > doubt, map it as land" since we don't have the luxury of being able to map > > average high water marks or highest spring tide mark that a government > > agency might use. If it is something that I can walk out and see most of > > the day or year, then I think it should be mapped as land as a navigation > > aid. > > > > It might also be worth considering a natural=mangrove area tag. Our > > current system is biased towards temperate climates. I've hesitated so far > > as it is often very difficult, either on the ground or from imaging data, > > to map the inland extent. > > > > Mike > > > > At 03:27 AM 9/07/2008, Stephen Hope wrote: > >> The northern coast of Australia has many Mangrove marshes at river > >> mouths, some of them extending many kilometres away from the dry shore > >> line. PGS shows these areas as sea, because they are not dry land - > >> and that is were the coastlines would have been imported from. Note > >> that "being submerged for half the year" doesn't mean the trees are > >> covered with water, just the mud under them. The tree tops would be > >> above water all the time, I suspect. > >> > >> We've (mostly) tagged them as land, with the coast being on the sea > >> side of them. Technically they may be water covered (or partially > >> water covered, usually about 6 inches deep), but if you can't swim or > >> boat in them and plants and trees grow there it's land as far as I'm > >> concerned. They certainly are not ocean. Marshes in the UK are also > >> treated as land from the coastline point of view, even were they edge > >> an ocean. > >> > >> See > >> http://www.openstreetmap.org/?lat=-16.9642&lon=145.7843&zoom=13&layers=B00FTF > >> for an example near Cairns. More examples are further up the coast. > >> > >> Stephen > >> > >> > >> 2008/7/9 Alan Millar <[EMAIL PROTECTED]>: > >>> I came across an interesting area which I don't know how to map or tag. > >>> > >>> http://www.openstreetmap.org/?lat=22.066&lon=89.047&zoom=9&layers=B00FTF > >>> > >>> This is the Sundarbans mangrove forest on the border of India and > >>> Bangladesh. The map doesn't look like much, but look at the map with > >>> aerial photos like in Potlatch edit mode and it starts to get interesting. > >>> > >>> I read that it is submerged for up to half of the year. The Yahoo aerial > >>> photos clearly show the forest areas, so I assume they were taken at a > >>> low-water period. Google Maps shows it as land. > >>> > >>> Our oceantiles file has it as land, but our coastlines treat it as sea. > >>> Our coastlines stop at the farmlands which border it. During the high > >>> water period, I suppose our coastlines make sense. > >>> > >>> Does anyone have any recommendations of how to treat an area like this? > >>> Any similar geography already mapped somewhere? Thanks > >>> > >>> - Alan > >>> > >>> > >>> > >>> ________________ > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.6 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org > > iD8DBQFIdSv1JfMmcSPNh94RAty+AJ9voJsnb9ym6eiFMB9dNJFaHg5WpACfUWAO > we9MgNpK8v5miRbnCw+4tU4= > =tGCg > -----END PGP SIGNATURE----- > > > _______________________________________________ > talk mailing list > [email protected] > http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk -- Ulf Mehlig <[EMAIL PROTECTED]> ----------------------------------------------------------------------- _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
