User:Rudolf/draft landcover

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Proposal

landcover=* is the observed (bio)physical cover on the earth's surface.

It describes what you can actually see in bird's eye view or in aerial photography, independently if it is biological or geological. This can be the tallest plants (e.g. trees) or the naked surface (e.g. bare rock).

landcover=* is dedicated to describe the whole earth's surface with only one key. It is not dedicated to detailed mapping in urban environments, although you can do it.

All areas in the landcover features of natural=* will be transfered to landcover=*. Alternatively this tags can be tagged double, with a lot of redundand data.

The tags landuse=grass, landuse=forest and landuse=railway will be transfered to landcover=*.

The main concept relates to the NLCD92 - National Land Cover Database (table). Some values relates to the LCCS - Land Cover Classification System (table).

Rationale

  • Landcover is what you can actually see in bird's eye view or in aerial photography. It is what faces the sky: Tallest plants (not one by one), barren soil, barren mountain rocks etc. Landcover can only be tagged on areas, not on ways or nodes. It incorporates the whole earth's surface, without oceans.
  • Surface is the upper layer of the planet if vegetation etc. is hypothetically stripped off. This may be a natural surface such as rock, sand, soil, water or a man made surface such as asphalt, concrete, paving stones, or pebble stones. Surface is mostly tagged on mad-made barrent things such as the active parts of roads, plazas, sports pitches etc., but may also be tagged where the surface beneath a landcover is unusual, such as trees growing on sand. Surface can be tagged on areas but would mostly be used on ways and points that already carry a primary tag which makes it relevant. For instance a way tag as a highway will often have a surface to indicate if and how it is paved.
  • Landuse is the how an area is used, which may or may not related to its landcover and/or surface. Land use tags should be used where the use is known and not implied by some other tag. Common uses in topography maps are residential area, cemetery, cropland, meadow, orchard and vineyard.

The current situation

Today OSM lacks a consistent tagging scheme for the earth's surface.

Landcover information is already provided, mainly by natural=* and landuse=* and surface=*.

natural=* is a mishmash of landcover features (e.g. wood) and landscape features (e.g. single tree, tree_row). This is disturbing to a simple and consistent tagging of the earth's surface.

natural=* contains some overlapping features such as natural=sand/natural=beach or natural=bedrock/natural=bare_rock/natural=rock or natural=grassland/natural=fell.

There are ambiguous tags, e.g. natural=fell describes a form of vegetation and also mountain peaks, natural=rock describes areas of rocks and is used on 140.000 nodes.

There are undocumented tags, e.g. natural=mud.

There are similar-sounding tags, e.g. natural=bedrock, natural=bare_rock, natural=rock, natural=stone.

There are many features in water=* that don't belong to natural=*, eg. reflecting_pool, reservoir, canal, lock, moat, wastewater. We have water=reservoir and landuse=reservoir.

There is a problematical determination between natural=wood and landuse=forest.

There is no tag for areas of perennial ice/snow on mountain tops or in the polar area.

There is no tag for all areas including infrastructure features.

The current tagging makes it impossible to tag some features. For example, a military area which is covered with woodland can't be tagged both with landuse=military and landuse=forest.

How to map

All landcover features are areas and can either be created as a closed way or as multipolygon.

Gaps between neighbouring areas are to be avoided.

There are 8 main values with 8 sub-keys. There are in total 36 subcategories.

Landcovers, incorporating the whole earth's surface
Tag Description Subtags Description Picture Deprecate
landcover=water Area of open water or permanent ice/snow cover. water=lake Area of water surrounded by land. Mount Pinatubo 20081229 01.jpg natural=water
natural=glacier
water=river Area of a wide river. Wilke.Aussicht.01.jpg
water=reservoir Artificial lake, used to store water. Lakevyrnwysummer.jpg
water=canal Area of a man-made channel for water. MurtfaltalrDanubeChannel.JPG
water=ice Area characterized by year-long surface cover of ice and/or snow. Glaciers, mountain tops, polar ice. Grosser Aletschgletscher 3178.JPG
water=* others
landcover=wetland Area where the soil is periodically saturated with or covered with water. wetland=swamp Swamps are wooded wetlands that are often flooded for a portion of the year. Swamp vegetation is dominated by trees and tall shrubs. Cypresses.jpg natural=wetland
wetland=marsh Marshes are wetlands that are periodically or permanently flooded with water. Marsh vegetation typically consists of non-woody plants such as cattails, rushes, reeds, grasses and sedges Cepkeliu marsh.jpg
wetland=bog Bogs are peat-filled depressions that receive their water and nutrients from rainfall. Peat consists of partially decomposed plants. They are frequently covered in shrubs rooted in the sphagnum moss and peat. Tourbière 03 - Parc de Frontenac - Juillet 2008.jpg
wetland=fen Fens are located in areas where groundwater discharges to the surface. Typical fen vegetation includes sedges and mosses, along with some grasses, reeds, low shrubs. Wicken-Fen-Hide.jpg
wetland=* others
landcover=grassland Area dominated by upland grasses. grassland=natural Natural/semi-natural grassland. Konza1.jpg landuse=grass
natural=grassland
natural=fell
natural=tundra
grassland=savanna Natural grassland with sparsed trees or scrubs. Savanna towards the south-east from the south-west of Taita Hills Game Lodge within the Taita Hills Wildlife Sanctuary in Kenya.jpg
grassland=tundra Alpine tundra: habitat above the treeline, characterised by open, low growing vegetation. Croix de Fer- View to South-West.JPG
grassland=urban Urban/recreational grassland. Traffic Island, Coulby Newham - geograph.org.uk - 91699.jpg
grassland=meadow Area of grassland, used for hay or pasture.
landuse=meadow
Okolí Huklivého 001.jpg
landcover=plantation Land used for growing crops or fruits. plantation=cropland Land used for growing crops.
landuse=farmland. See crop=*.
040719 172 dorset marnhull2.jpg
plantation=orchard Plantation of fruit trees or shrubs.
landuse=orchard
Lemon Orchard in the Galilee by David Shankbone.jpg
plantation=vineyard Plantation of grape-bearing vines.
landuse=vineyard
Aerial View - Landschaft Markgräflerland1.jpg
plantation=aquatic Cultivated aquatic or regularly flooded areas. Dili Reisfelder.jpg
landcover=woodland Area characterized by tree cover. leaf_type=broadleaved Broadleaved vegetation. WaldAlfeld.jpg landuse=forest
natural=wood
wood=*
leaf_type=needleleaved Needle-leaved vegetation. Swiss National Park 131.JPG
leaf_type=mixed Broadleaved and needle-leaved vegetation. 09272008 BrightonUT.JPG
managed=yes Woodland is managed/maintained.
leaf_cycle=evergreen/deciduous/mixed Leaf phenology.
cover=closed/open/sparse Proportion of a particular area covered by plants.
landcover=shrubland Area characterized by woody vegetation with aerial stems, generally less than 6 meters tall, without interlocking. shrubland=scrub Uncultivated land covered with bushes or stunted trees. Starr 010831-0016 Morella faya.jpg natural=scrub
natural=heath
natural=tundra
shrubland=heath Vegetation dominated by dwarf shrubs of the heather family. Lüneburger Heide 109.jpg
shrubland=tundra Arctic tundra: treeless habitat, characterised by open, low growing vegetation. Fjällväxter - Norwegian hills near Sweden.jpg
landcover=bareland Bare(barren) land, with little or no "green" vegetation. bareland=sand Area covered with sand. Libya 4608 Idehan Ubari Dunes Luca Galuzzi 2007.jpg natural=sand
natural=beach
natural=mud
natural=bare_rock
natural=bedrock
natural=rock
natural=scree
bareland=bare_soil Area covered with earthen material. Duerre.jpg
bareland=hardpan Hardpans are surfaces that have been indurated due to chemical or physical processes. Also dry lake, salt pan. Salar Uyuni Bolivie.JPG
bareland=gravel Area covered with loose rock fragments. Scree, gravel beach. Scree.jpg
bareland=stones Area covered with stones. Stone desert. 260 Boa Vista.jpg
bareland=bare_rock Area covered with bare_rock. Hörnlihütte weg.jpg
landcover=artificial Artificial surfaces and associated areas. artificial=road Area covered by wide roads. Motorway-photo.jpg landuse=railway
artificial=railroad Area covered by wide railways. Passenger-rail.JPG
artificial=pipeline Area used for communication lines/pipelines. OilPipeAlaska.JPG
artificial=urban Urban area.
landuse=residential
New-York-Jan2005.jpg
artificial=industrial Industrial area.
landuse=industrial
Kraftwerk Moorburg (Hamburg-Moorburg).1.phb.ajb.jpg
artificial=extraction Extraction sites.
landuse=quarry
Arandis Mine quer.jpg
The values are somehow sorted by height of the vegetation zone. Many values relate to the NLCD 92 Land Cover Class Definitions. Some values relate to the Land Cover Classification System (LCCS).